eChapters

Introduction of Food Industry

India is one of the major food producers in the world. The food sector contributes to about 28% of India's GDP. India stands at 1st position in the world for production of cereals, milk, livestock, banana and Mango, 2nd in producing fruits and vegetables and ranks amongst top 5 in producing rice, wheat, groundnut, tea, coffee, tobacco, spices, sugar and oilseeds. India's share in global production of fruits is 10% and vegetables are 13.7%. The current consumption of fruits and vegetables is approx Rs.2 lakh crores at current prices with an estimated growth rate of 11% per annum. The growth rate is higher than cereals and milk and comparable to meet consumption

Status of Food Processing Industry

The food processing industry in India is still in a sorry state. The rural population comprising 70% including small cities, consume less than 10% of the processed foods and vegetables, whereas 60% of the processed food is consumed in four major metropolitan cities and 30% in the state capitals and big cities. Another fact is that 40% of the processed food and vegetables produced in the country in terms of value are bought by institutional buyers like Hotels, Restaurants and Defense etc. The highest growth in domestic market has been in fruit drinks, tomato ketch up and Jams.

There is another fact that India is the largest milk producer in the world, however, organized industry accounts for less than 15% of the milk produce in India. It is estimated that there may be a total production of 1100 million tons of production of food products mainly food grains, oilseeds, sugarcane and fruits/vegetables during 2011-12 and leaving marketable surplus of 870 million tons.

Food is basic to human being and agriculture is the catalyst between the two which is basically supported by natural resources. The human being is entirely dependant on food and food is fully dependent on agriculture and humanity. Eventhough food, agriculture and humanity have their own entity; they are inseparable for the survival and existence of each other. Hence, the three pillars of food, agriculture and humanity forming a triangle symbolize the roots of human civilization.

I find myself fortunate to have the opportunihj to live and experience the working life of the farmers and the farming in Kansas (USA), Nigeria (Africa), Saudi Arabia and Yemen (Middle East), Italy (Europe) and India, Myanmar and Thailand (Asia). It zvas fiirther strengthened by visits to farmers in another about 100 countries. Day after day and month after month and even years, it made me to realize that community culture, language and farming in each state, country and continent are different from each other but some things are common and that they are all doing farming, they are growing food and they all doing for the livelihood of their families, neighbors and communities near and far (Nath, 2011).

The foundation of agriculture is laid on available natural resources e.g. land, water, sunlight, air, plant, animal and human beings. The human beings, being the leader to manage the resources have contributed to redefine agricultural science and promote and develop technology. This has led to augment agriculture and its science and technology. At the end, the human efforts have brought about changes and improved agriculture production at the cost of excessive use of natural resources, knowing well that without natural resources, without good soil and water hardly anything will survive.

Presently world produces enough to feed the present human population, but it is not available to millions of people. It is not the lack of availability of food but is the unequal distribution and lack of entitlement which are causing hunger and malnutrition in millions of population.

1. INTRODUCTION

It is hard to conceive which came first on earth, human being or food. If the human was born first, he or she needed food immediately to survive. Thereafter, the human beings continued to need food and continued to eat food throughout his or her life. Hence, the relationship between human being and food is permanent and the requirement of food for the human being to be alive is everlasting. Further, sources of food may survive in nature without human intervention but human being can not remain alive without food. This clearly signifies the permanent bondage of human being and food which is inseparable under any circumstances. ‘Thus, should we state that every human being necessarily needs food and should have right to food as soon as born.

In order to further strengthen this view, the governance which rules human beings should also be protective and enact laws to ensure food to each human being born in respective countries.

2. BACKGROUND

•   “Hunger is exclusion”, wrote de Castro (1963) a Brazilian anti-hunger advocate. “Exclusion from the land, from jobs, wages, income, life and citizenship. When a person gets to the point of not having anything to eat, it is because all the rest has been denied. This is a modern form of exile. It is death in life”.

•   Simply by being born, everyone has the right to food. A person doesn’t have to do anything to “deserve” it; the right to food is a birthright. But this does not entitle a person to sit back and ask for free food. People are responsible for doing all they can to realize their own right to food. Governments that are parties to the International Covenant on Economic, Social and Cultural Rights are responsible for ensuring that all those living within their borders have the means to do so, (FAO, 2007).

•   Broadly speaking, governments should create peaceful, stable, free and prosperous environments in which people can feed themselves in dignity. Even without a legal obligation to do so, countries have a moral obligation to ensure freedom from hunger (FAO, 2007).

1. INTRODUCTION

The paradigm of world’s livelihood is built on the basic foundation of natural resources which includes humans, plants, animals, soils and minerals, water and air. But the very livelihood of these resources are at stake because they are strongly linked and dependant on each other. And to add, the material resource namely ‘economy’ has invaded the tranquil habitat and life of the community of natural resources. Thus the present crisis is challenging livelihood of each of these natural resources whether it is human, plant or water or earth and the element of economy is interfering with the natural recourse of human depending on water and soil; and human, plant, animal together are depending on soil, water and air. But when the livelihood of soil, water and air is at stake how human, plant and animal can survive; hence the design of livelihood of world has the essential ingredients of all natural resources.

We humans are selfish and concerned about our livelihood security only and try to over-exploit other natural resources and assumed themselves as the master of all natural resources. Practically, there is war going on between and among natural resources. The world could be better if each natural resource has its own right with prospects to safeguard its livelihood and all resources together with better livelihood could offer the lively world.

2. UTILIZATION OF NATURAL RESOURCES

We should underscore that none of the natural resources are in ‘plenty’ and that we should ‘economize’ on each natural resource to build together the world’s livelihood. The food security of humans can not be attained without plants and plant security can nor be achieved without soil and water and it is impossible to keep secured soil and water without economics of management.

In short, the livelihood security of humans is entirely dependant on all other natural resources coupled with the material resource economy. It is incumbent on us to initiate appropriate steps from gross root to policy levels to make the world better.

SYNOPSIS

Until recently, agriculture was primarily valued for producing staple cereals. Today, there is increasing recognition that agriculture has an important role to play in improving nutrition, human health and environmental health. Helping agriculture successfully forge links with nutrition and health can enable the research, development and policy communities to more effectively address the looming challenges of hunger, malnutrition and agriculture-associated diseases. Already, there is growing momentum around the world to bring these sectors together to improve food and nutrition security of the world’s poorest people.

Keywords : Food security, nutrition, health, agriculture.

1. INTRODUCTION

During the past fifty years, the world has made substantial progress in improving the food security of millions of people. Using science and technology, agricultural extension and appropriate policies and incentives complemented with infrastructure, farmers, researchers and policymakers have worked together to increase the global production of cereals, cutting the proportion of hungry people from approximately one-third to one-sixth of the world population (Spielman and Pandya- Lorch 2010). Yet more needs to be done. Nearly one billion people still suffer from hunger. Micronutrient deficiencies affect billions more today and potentially in the long-term. Malnourishment in children’s first two years of life, for example, causes largely irreversible damage, impeding their physical growth and intellectual development, increasing their susceptibility to diseases such as diabetes and cancer and even drastically reducing their incomes as adults. Undernourished women are more likely to give birth to smaller babies, thereby creating an inter- generational trap of under nutrition and poverty.

While agriculture has traditionally been put to work to raise the productivity and production of staple crops, there is increasing recognition that agriculture is also key to improving nutrition security, individual health and environmental health. This nuanced understanding has come just in time, considering the looming challenges of hunger, malnutrition, climate change and its link to energy and resource scarcity and urbanization. Placing agriculture in this larger context may enable the global community to better address and cope with these challenges, whilst meeting the food and nutrition security needs of the world’s most vulnerable people.

This paper will briefly review the evolving role of agriculture in meeting food and nutrition security. It will identify emerging challenges, describe promising developments and highlight opportunities for leveraging agriculture-nutrition-health links to overcome challenges.

1. INTRODUCTION

India is principally an agricultural country with seventy per cent of its population living in villages and fifty nine per cent of the total work force dependent on agriculture for its daily bread. Almost 20% of the gross GDP is contributed by agriculture. A steep surge in production since late 1960s has made country self-reliant in food grain production with buffer stocks full to the brim. Since independence, 0.66% growth/ year in gross agricultural area combined with 2.67%/year increases in food grain production led to a net increase in per capita food grain availability from 395 g/ day to 475 g/ day. An outstanding achievement, as it happened despite an unabated population build up at a rate of 2.15 %/ year or 13 million more mouths to be fed every year. Not only in food grain production, the country has made revolutionary progress in milk, fish, eggs, fruits and vegetable production also (NAAS, 2004).

Needless to say that the economic growth of our country depends largely on the prosperity of the agriculture. The agricultural sector acts as a bulwark in maintaining food security as well as national security. The first and the foremost role of agricultural is its promotion of economic progress in the country by enlarging the savings of the rural sector and making them available for the development of industries. Gandhiji, the father of the nation called “Agriculture as the soul of India”. Also, agriculture has been termed as “The mother of all industries and the maintainer of human life standing at the need of all sciences and arts, indeed, at the head of civilization and progress”. The significance of agriculture in India arises also from the fact that the development in agriculture is an essential condition for the development of the national economy. Thus any change in the agriculture sector- positive or negative- has a multiplier effect on the entire economy (Rekha & Rangappa, 2010).

Over 70 years ago, Mahatma Gandhi made the following observations while addressing youth who wanted to serve rural India:

‘The fact is that the villagers have lost all hope. They suspect that every stranger’s hand is at their throats and that he goes to them only to exploit them. The divorce between intellect and labour has paralyzed our agriculture. The worker should enter a village full of love and hope, feeling sure that where men and women labour unintelligently and remain unemployed half the year around, he working all the year round and combining labour with intelligence cannot fail to win the confidence of the villagers’.

This message is as relevant today as it was 60 years ago. Integrating brain and brawn in farm enterprises should hence be the purpose of agricultural education. (ICAR, 1997)

SYNOPSIS

This millennium has brought about serious challenges as well as excellent opportunities for the betterment of humanity. The migration of rural population to urban areas is one of the major challenges foreseen. It is expected that much of the population growth is expected to take place in the cities of the developing world. By 2020, about 52 percent of the developing world’s population will be living in urban areas (IFPRI, 1999). The agricultural areas around cities offer great promise to urban and peri-urban agriculture.

The interventions on Urban and Peri-urban Agriculture (UPA) suggested and initiative undertaken by FAO is timely and valuable in the interest of the teeming population demanding for both nutrition and health. The International Conference on Vegetables (ICV-2002) held during 2002 has emphasized the importance of vegetables; FAO International Workshop on Urban and Peri-urban Agriculture for Asian Countries organized during 2005 had amply emphasized the important role of horticulture; and the International Conference on Horticulture (ICH-2009) held during 2009, has amply illustrated the importance of horticultural crops particularly vegetables in UPA for the benefit of urban population.

The urbanization process is a reality that drives people to go and live in the cities. It is very pronounced in Latin America where already 85% of the population lives in cities; in Asia the average is reaching 60% whereas in Africa the phenomenon has started later and has now reached 35%. Besides the increased demand for food, there has been a rapid increase of poverty, unemployment, hunger and malnutrition in the Urban and Peri-urban environment around the world that are of great concern to central and municipal authorities.

UPA can contribute to feeding the urban population, generate income and employment and thereby reduce poverty. In reality many countries have already UPA related activities going on in areas of horticulture including vegetables, dairy production, small livestock, aquaculture and forestry. However, it has been realized that very few countries had actually investigated the real opportunities and constraints linked to the urban agriculture sector.

Keywords : Urban Agriculture, Urban Food, Peri-urban Agriculture, UPA.

During the last 50 years or so, the world has witnessed tremendous changes in terms of population exodus, accessibility to food, advancement in agricultural science and technology, increased food production, efforts in mitigating food and nutrition security, natural and human made disasters and developmental efforts in handling and containing national and global issues. Inspite of these efforts, the challenges which have cropped up are plenty and at the same time creating avenues of opportunities to address those challenges in the interest of humanity. The world is large, countries are many, agro- climatic regions vary significantly, socio-economic conditions are distinct and the national, regional and global issues vary greatly. For ease of presentation and convenience of illustration, common issues only will be dealt in this chapter. Keeping in view the theme of this book, the following topics/issues will be discussed which pose challenges for the living humanity and for future generation within next 50 years. The views are limited to developmental, planning and implementation processes only in order for governments and others to consider overcoming these challenges.

With the advent of modern crop varieties, better irrigation facilities and greater use of fertilizers and other inputs country has changed within the last 50 years from a region of food scarcity to a region of food sufficiency. The greenrevolutiontechnologiesinvolvinggreateruseofsynthetic agro-chemicals such as frrertilizers and pesticides with adoption of nutrient- responsive, high yielding varieties of crops have boosted the production per unit area under different crops and cropping systems. However, this increase in production has slowed down and in some cases there are indications of decline in growth of productivity and production (Table 1). These production scenarios may be envisaged as corresponding decrease in soil organic matter and continuous increase in multi nutrient deficiency (Dwivedi et al., 2006). If such situation is allowed to continue for another few decades, there are chances that todays’ productive land may become unproductive. The declines in yield and production fatigue have been noticed in various cropping systems of different agro-eco region (Gill and Singh, 2009). Farmers’ participatory surveys conducted in Indo-Gangetic Plain (IGP) region indicates that farmers’have resorted higher doses ofnutrients each year to obtain the same yield as obtained in previous year (Dwivedi et al., 2001). The probable reasons behind these are continuous mining of nutrients, inadequate use of organic sources, imbalance fertilization and decline of soil organic matter.

Rice-wheat (RW) is the major cropping system occupying about 10.5 mha in the IGP of India. It contributes more than 60% of the foodgrains to the central pool. With shrinking land resources and burgeoning population, the RW system will be under pressure to produce more grain output per unit area in the coming decades. Meeting this challenging task requires sustainable management of soil, water and plant nutrient resources. High yields of the irrigated RW system result in production of huge quantities of crop residues. Total production of crop residues in Punjab is about 47.2 mt which includes paddy straw, wheat straw, cotton sticks, sugarcane leaves, maize stalk, and other oilseeds and pulse residues (Beri and Gupta, 2003). Wheat and rice straw constitutes more than 70% ofthe crop residues produced in the country. Paddy straw alone constitutes more than 50%. Cotton and sunflower residues are generally used as fuel. Sugarcane trash (leaves) is generally burnt in-situ or used as fuel after collection from the field. Increasing constraints of labour and time have led to the adoption ofmechanized farming in the highly intensive RW cropping system. Approximately 91% ofthe total rice area is mechanically harvested, while 82% of the total wheat area is mechanically harvested. Traditionally, wheat and paddy straws have been removed from the fields for use as cattle feed and for several other purposes such as livestock bedding, thatching material , for houses, and fuel. While more than 80% ofwheat residue is collected by the farmers after combine harvesting and often fed to animals, paddy straw is considered poor feed for animals due to its high silica content.

Substantial loss ofplant nutrients (especially N and S) and organic carbon occurs during burning of crop residues, with important implications to soil health. About 40% of the N, 60-85% of the K, 30-35% of the P, and 40-50% of the S absorbed by rice remains in the vegetative parts at maturity. One tonne of paddy straw contains approximately 6-7 kg of N, 1.0-1.7 kg of P₂O₅ and 14-25 kg K₂O. Apart from huge loss of precious plant nutrients, burning of crop residues depletes soil health. Air pollution from stubble burning also impacts human and animal health both medically, and by traumatic road accidents due to restricted visibility. In view ofthe serious problems associated with the residue burning, new ways are being sought to efficiently utilize the huge amount of surplus residues produced in the country.

All the states have some area under irrigation. Thus the term ‘irrigated ecosystem’is rather loosely defined, and the states having distinctly large net irrigated area may constitute this ecosystem. Two such areas can be easily carved out i.e., Indo-Gangetic Plain region representing five states namely Punjab, Haryana, U.P., Bihar and West Bengal, and coastal areas of two southern states i.e., A.P and Tamil Nadu. About 56% of the net irrigated area of the country exists in these states, and the cropping intensity is also much higher (144%) as against national average of 132%. With demographic viewpoint also, these areas are densely populated. Of late agriculture in this ecosystem has become unsustainable owing to over-exploitation of natural resources. Studies have conclusively established the superiority and worth of integrated nutrient management in restoration of soil health and sustenance of crop productivity and profits.

The basic concept underlying the principles of integrated nutrient management (INM) is the maintenance, and possibly improvement, of soil fertility for sustaining crop productivity on long-term basis. This may be achieved through combined use of all possible sources of nutrients and their scientific management for optimum growth, yield and quality of different crops and cropping systems. INM is not a new concept, but an age-old practice. Its importance was, however, not realized earlier due to low nutrient turn over in soil-plant system and almost all the nutrient needs were met through organic sources, which supplied secondary and micronutrients also besides major nutrients. INM has now assumed great significance mainly because of two reasons. First, the need for continued increase in agricultural production based on increase in per hectare yields requires growing application of nutrients, and the present level of fertiliser production in india is not enough to meet the total plant nutrient requirement. Second, the results of a large number of experiments on manures and fertilisers conducted in india and other countries reveal that neither the chemical fertilisers alone nor the organic sources exclusively can achieve the production sustainability under intensive cropping systems (Hegde and Dwivedi, 1993). Even the so called balanced use of chemical fertilisers would not be able to sustain high productivity due to emergence ofthe deficiencyofone ormore ofthe secondaryandmicronutrients (Swarup and Wanjari, 2000). The interactive advantages of combining organic and inorganic sources of nutrients in INM have proved superior to the use of its each component separately. The advantages of INM can be broadly enumerated as following:

Limited availability of additional land for crop production, along with declining yield growth for major food crops, have heightened concerns about agriculture’s ability to feed a world population expected to exceed 7.5 billion by the year 2020. Decreasing soil fertility has also raised concerns about the sustainability of agricultural production at current levels. Future strategies for increasing agricultural productivity will have to focus on using available nutrient resources more efficiently, effectively, and sustainably than in the past. Management of the nutrients needed for proper plant growth, together with effective crop, water, soil, and land management, will be critical for sustaining agriculture over the long term. Plants, like all other living things, need food for their growth and development. Growth is the function of various factors like light, carbon dioxide gas, water and mineral nutrients. Plants require 16 essential elements. Carbon, hydrogen, and oxygen are derived from the atmosphere and soil water. The remaining 13 essential elements (nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, iron, zinc, manganese, copper, boron, molybdenum, and chlorine) are supplied either from soil minerals and soil organic matter or by organic or inorganic fertilizers. For plants to utilize these nutrients efficiently, light, heat, and water must be adequately supplied. Cultural practices and control of diseases and insects also play important roles in crop production. Each type of plant is unique and has an optimum nutrient range as well as a minimum requirement level. Below this minimum level, plants start to show nutrient deficiency symptoms. Excessive nutrient uptake can also cause poor growth because of toxicity. Therefore, the proper amount of application and the placement of nutrients are important.

Sustainable agriculture warrants a wise management of natural resources and inputs to satisfy human needs in the fast changing scenario while maintaining, if not improving, the quality of environment. Soil as a natural resource is facing more and more serious degradation threats under modern agriculture. Incidence and expansion of multi-nutrient deficiencies in Indian soils owing to inadequate and unbalanced nutrient input through fertilizers is considered one of the major reasons for decline in factor productivity of crops. The problem of soil fertility depletion is spectacular across the soil types and agro-climatic zones, but it is more acute in intensively cropped areas, where annual nutrient removal by the crops often far exceeds replenishments. Recent diagnostic surveys indicate that in several high productivity areas of irrigated ecosystems like, Trans-and Upper Gangetic Plain zones, farmers are resorting to even excessive use of fertilizers, especially N, to maintain the yields at levels attained previously with lower fertilizer application rates. With an unabated deterioration in soil health in general, and soil fertility in particular, and a mounting pressure on finite land resources due to increase in population, the interest in soil fertility and soil health has revived due to several reasons:

Stagnation in growth rates of production and productivity of staple foodgrains - threat to food security

Decline in factor productivity, thus increasing cost of production

Nutrient withdrawals in excess of replenishment

Low nutritional value of food and feed grown on nutrient-starved soils - threat to nutritional security

Poor quality of produce fetching low price - threat to economic security

Post independence era brought about a radical change in agricultural scenario which improved economy and living standard of Indian farmers to a great extent. Green revolution, (field crops) during early sixties followed by white revolution (milk) and thereafter yellow (oilseeds) and blue (fish) revolutions made the country not only self sufficient in most of the food commodities but also exporter in many. Several calamities including droughts, floods, and ill effects of national and international conflicts faced by the, people of the country during post independence era could not affect the economy and stability of the country much because of rich agricultural heritage. As usual, the rapid and rather un-planned development creates several problems and this was true in our conditions too. Loss ofindigenous land races, depletion of soil nutrients and water resources, creation of salinity and water logging, resurgence of pest and diseases, declining factor productivity and farm profits and increased environmental (air, water & soil) pollution are among such problems have great concern to agricultural scientists and planners in coming future. The situation further aggravated because of industry oriented government policies and globalization which supported growth of industries and trades rather than agriculture and hence the growth rate in these sectors was considerably high. This fact is more visible by the figures on relative contribution of different sectors in the national GDP during last sixty years (Table 1). At the time of independence of the country more than 75% people were depend on agriculture related occupations which came down to mere 67.4% in 2009-10. Similar is the case of total contribution of agriculture in national GDP which decreased from 57% in 1951-52 to as low as 14.6% in 2009-10. Besides government policies, major factor identified responsible for degradation of resources, stability in production and decreased factor productivity is chemical based farming and that too in imbalanced and improper methods of application practiced by the farmers for getting more andinore production and profits per unit area per unit time The solution of this lies in the increased use of organic sources of nutrients in proper ratio along with chemical fertilizers - IPNS (Integrated Plant Nutrient System). Livelihood of marginal and small land holders who represent a large section (more than 86%) of farming community and remained deprived of advancements in the, field of agriculture has been the main agenda of the Indian Government in Xlth, five year plan and to continue in Xllth plan too. To ensure livelihood improvement with focus on small and marginal farmers Integrated Farming System (IFS) has been proved to be an effective approach. Accordingly, the Project Directorate of Cropping Systems Research renamed as Project Directorate for Farming Systems Research with AICRP on Integrated Farming Systems Research and Network Project on Organic Farming mandated with farming systems perspectives. Since, integrated farming system is a holistic approach wherein all the wastes and residues are recycled within the system and nothing go waste. Output of one enterprise is used as input for the others. This way, farming becomes more economic and environmentally safe.

Food security, nutritional security, sustainability and profitability are the main foci ofpresent agricultural scenario in India. In the absence of additional land for bringing under plough vertical growth in agriculture through intensive cropping and enhanced productivity becomes inevitable. Intensification of agriculture to meet the growing needs of the burgeoning population has brought with it numerous productivity related constraints. It has triggered multiple nutrient deficiencies in soil and this has raised doubts on the soils capacity to sustain anticipated production levels. One of the key inputs in enhancing and maintaining the productivity ofintensified agricultural systems is chemical fertilizer which provides nutrients in readily available form. But long term experiments on various cropping systems at various agroecological regions and soil types revealed that continuous use of chemical fertilizers in unbalanced and indiscriminate manner deteriorates the soil health and leads to deleterious effect on long term soil fertility and yield sustainability. Apart from the soil productivity issue, the use of chemical fertilizer is also becoming more and more costly due to scarcity during peak demand. The excessive use of chemical fertilizers is not only costly but they pollute the production environment (Singh et al., 2005; Dwivedi et al., 2003).

In the coming decades, a major issue in designing sustainable agriculture system will be the management and rational use of organic inputs such as animal manure, green manure, crop residues and biofertilizers etc. (Powlson, 1994). Long term studies indicated that current fertilizer recommendations are inadequate for maintaining yields (Bhandari et al., 2000; Singh and Mishra, 2010; Tiwari et al., 2006). It is, therefore, to sustain high crop yield without deterioration of soil fertility it is important to apply required amount of plant nutrients through fertilizers in combination with organic sources, crop residues, biofertilizers etc.

Rice-wheat is a dominant cropping system in the Indo-Gangetic Plains covering approximately an area of 10.5 million ha. Modern agricultural production practices have emphasized the widespread use of fertilizers as a source of nutrients. The continuous use of high levels of chemical fertilizers over a prolonged period, decline in area under legumes and reduction in the use of organic manures has resulted in soil degradation and environmental pollution. It is estimated that the gap between nutrient removal by crops and addition through fertilizers in India will remain at level of 8-10 million tones per annum. Such negative nutrient balances are depleting the soils of their nutrient reserves resulting in acute deficiencies of nutrients. Integrated plant nutrient supply (IPNS) is an important component of sustainable agricultural intensification. The goal of integrated nutrient management (INM) is to integrate the use of all natural and man-made sources of plant nutrients, so as to increase crop productivity in an efficient and environmentally benign manner, without diminishing the capacity of the soil to be productive for present and future generations. The INM is made up of components which possess great diversity in terms of chemical and physical properties, nutrient release efficiencies, positional availability, crop specificity, and farmers’ acceptability. Since organic manures cannot meet the total nutrient needs of modern agriculture, integrated use of nutrients from fertilizers and organic resources seems to be a need of the time. For INM to make desirable progress and find wide acceptance, nutrient supply packages for important agroecological environments need to be developed. These should be technically sound, practically feasible, economically attractive and socially acceptable. Integrated plant nutrient systems can ensure long-term sustainability of agricultural growth through improvement in soil health and will significantly reduce the needs for chemical fertilizers. The complementary use of chemical fertilizers and organic fertilizers may increase the efficiency of chemical fertilizers in order to maintain a high level of crop productivity. Because of low primary nutrient content and thus the need for large applications per unit area, farmers and policy makers are often reluctant to adopt and promote the use of organic fertilizers. The different components of INM possess great diversity in terms of chemical and physical properties and nutrient release patterns.

Oilseeds serve as rich source of food, feed, energy, employment and commerce. The productivity of oilseeds in India (1006 kg ha^-1 during 200809) is very low when compared with the world productivity (1878 kg ha^-1 during 2008). The oilseeds production in the country often sufers from a high degree of variation in annual production owing to their predominant cultivation under low and uncertain rainfall situations which is further handicapped by input starved conditions with poor crop management. Nutrient and water are the key inputs for crop production. Improving efficiency and factor productivity under complexities of diminishing quality resources and increasing ecoawareness are critical for sustainable oilseeds production.

The vegetable oils consumption in the country is steadily rising and has sharply increased in the last couple of years touching around 14.1 kg head^-1 year^-1 during 2009-10. As per DAC-Rabo Bank, India’s per capita consumption is likely to reach at least 16.38 kg year^-1 by2020 and for a projected population of 1331 million, vegetable oil requirement will be 21.8 million tonnes. This is equivalent to about 66 million tonnes of oilseeds assuming that there is no change in the proportion of different oilseeds produced in the country in the next ten years. Assuming about 20% of vegetable oils contribution from sources like ricebran, cotton seed, coconut, oilpalm, etc., still the country needs to produce about 55 million tonnes of oilseeds by 2020. Considering that the oilseeds production during 2008-09 was just 27.56 million tonnes, the country needs to double oilseeds production in next 10 years requiring a growth rate in excess of 6%

The population of India is estimated to touch 1.4 billion by the year, 2025, which will need at least 300 million tonnes of food grain. This necessitates the production of additional food grain from the same land without loosing the production potential of the soil. This, in turn, requires extensive research to provide a scientific basis for enhancing and sustaining food production as well as soil productivity with minimum environmental degradation. In order to attain this it is essential that the amount of nutrients removed from the soil should be replenished through judicious use of fertilizers and manures. This needs a more comprehensive approach for fertilizer use, incorporating components like soil test, field research and economic evaluation ofthe results. Soil testing is one of the best scientific means for quick and reliable determination of soil fertility status. Soil test crop response study in the field provides soil test calibration between the level of soil nutrients as determined in the laboratory and the crop response to fertilizers as observed in the field for predicting the fertilizer requirements of the crop.

Objectives of soil testing.

Soil testing provides a sound information about the suitability, fertility and productivity of the soil. This enables the farmers to make the most profitable use of some of the costly inputs in farming. However, lack of information among the farmers about soil testing and their importance in management of resources necessitates that the work of soil testing should be taken extensively. Soil testing is a useful tool for making fertilizer recommendations for various crops and cropping sequences as well as reclamation of problem soils. Thus the major objective of soil testing are to identify the type of soil related problems like salinity, alkalinity, and acidity and to suggest appropriate reclamation/amelioration measures and to evaluate the fertility status in terms of available nutrients for making soil test based fertilizer recommendations.

Soybean [Glycine max (L.) Merrill] is the leading oilseed crop in the world. Its area and production are far ahead of other oilseeds at the global level (Table 1). The commercial cultivation of this crop in India started in the early 1970’s. Within a span of 4 decades its spread has been phenomenal and today it occupies around 9.67 million hectares with a production of about 10.22 million with an average productivity of around 1006 kg ha^-1 (DSR, 2010) (Table 2). It is now the fourth largest among field crops after rice, wheat and maize (GOI, 2007) in India and has become the leading oil seed crop surpassing groundnut and mustard and rapeseed. It is contributing nearly 37% to the total oilseeds produced in India. The central India comprising the states of Madhya Pradesh, Maharashtra and Rajasthan account for more than 95% of the total area under this crop. Chhattisgarh, Karnataka, Andhra Pradesh, Uttar Pradesh etc account or the bulk ofthe rest ofthe area. It is predominantly a rainfed crop with only about 3% of the total area getting some assured irrigation facility. Further, it is concentrated in areas which receive lesser rainfall in its early vegetative phase. A large number of crops have been replaced by soybean to a variable extent in its march towards achieving its present position. Badal et al. (2000) have reported that a large number farmers switched over to this crop from sorghum, groundnut, maize, cotton etc in the state of Madhya Pradesh owing to greater yield potential even under adverse conditions (Table 3). Further, it has become an integral part of several cropping systems including both intercropping and-sequential cropping systems in different parts of the country.

The apparent reasons for undesirable productivity under intensively cultivated areas are depletion of native nutrient reserves, emergence of multinutrient deficiencies, and consequent decline in factor productivity of applied nutrient (Dwivedi et al., 2006; Yadav, 1998; Yadav, 2003). Surveys conducted at PDFSR in different agro-climatic regions of Indo- Gangetic Plain indicated that in order to achieve previously attained yield levels, farmers have started applying greater doses of N than the recommended ones (Dwivedi et al., 2001; Sharma, 2003). Such indiscriminate use of N is likely to further worsen the nutrient imbalance in soil-plant systems, besides increasing the pest incidence, cost of production and environmental problems (Dwivedi et al., 2001). The annual productivity of rice - wheat could hardly exceed 9 t ha^-1 in the multilocation experiments on yield maximization (Dwivedi and Singh, 2011). On the other hand, long-term experiments (Singh and Mishra, 2010) and other studies indicate that crop productivity can be sustained with balanced fertilization, taking into account the emerging deficiencies of secondary and micronutrients (Tiwari et al., 2006)

Nutrient management is a major component of a soil and crop management system. It becomes even more important in intensive high yielding cropping systems because of the higher investments at stake. The SSNM is applying those concepts to areas within a field that are known to require different management options from the field average. Site specific nutrient management is a concept that can be applied to any field and any crop. Yet, it is most often thought of in relation to use of computer and satellite equipment, and does not require large farming operation. The technology tools certainly expand the capabilities for using site-specific management. This is really a “repackaging“ of management concepts that have been developed and promoted for many years.

India is a leading vegetable producing country in the world. Presently it occupies 7.981 million hectare area with the annual production 129.077million tones (2008-09). The country being belessed with the unique gift of nature of diverse climate and distinct seasons, make it possible to grow an array of vegetables number exceeding more than hundred types. However, potato being the staple food and easy to mix in several preparations ranks first (26.6%) in total production of vetetables followed by onion (10.5%) and other important Solanaceous vegetables like tomato (8.6%), brinjal (8.0%). Cauliflower and cabbage are most preferred winter vegetables and their total share in the country’s vegetable production is 5.1 and 5.3%, respectively. Other important vegetables, which are primarily grown in the country, are okra, onion, vegetable peas and a good range of cucurbits (Fig. 1)

There is miss-match in area production and productivity of vegetables among various states of the country. The West Bengal ranks first in the total production of vegetables in the country and its production during the year 2008-09 was in tune of more than 22.704 million tones, contributing the more than one-fifth of total country’s vegetable product ion. Uttar Pradesh, Bihar and Orissa in north India and Maharashtra, Tamil Nadu and Karanataka in south India are the other leading vegetable producing states in the country. In last one decade, there has been considerable progress in enchancing the productivity of vegetables which is presently 16.2 tonnes hectare^-1. Incessant growth of urbanization, ceaseless fragmentation ofland holdings and depleting natural resources are the major challenges before the expansion of any agricultural commodity either cereals or vegetables. Hence, our attention must be focused on vertical expansion strengthened with the boon ofthe technology instead of horizontal expansion just by increasing the crop area. To ensure the nutrition security of the burgeoning population of the country, it is estimated that up to 2020, the country’s vegetable demand would be around 155 million tones (Rai et al., 2004; Pandey et al., 2009). To achieve this target, it is sine qua non to integrate the various technologies right from production to post-harvest.

Protected cultivation of horticultural crops offers the best choice for diversification from traditional agriculture production system for a number of reasons. Production of crops under protected structures has great potential in augmenting production and quality of vegetables, flowers and in some fruit crops in main and off-season and maximizing water and nutrient use efficiency under varied agro-climatic conditions of the country. This becomes relevant to growers in India who have small land holding. They would be interested in a technology, which helps them to produce more crops each year from their land, particularly during off-season when prices are higher. The commonly protected structures are polyhouses, poly-tunnels, floating row covers, clotches, shade-net, insect-proof net and plastic-mulches (Chandra et al., 2000 ; Singh et al. 2010). These protected structures act as physical barrier and play a key role in integrated pest management by preventing spread of insect-pests and viruses which causes severe damage to the crop (Singh et al., 2003). This technology has great potential especially in periurban agriculture in near future, since it can be profitably used for growing high value vegetable crops like tomato, cheery-tomato, coloured peppers, parthenocarpic cucumbers, cut-flowers like rose, carnation, Berbera, lilium and fruits like strawberry, grapes etc. and for off-season cultivation of vegetables and their healthy and virus-free seedling production.

Protected cultivation is intended to mean some level of control over plant micro-climate to alleviate one or more of abiotic stresses for optimum plant growth. The microclimatic parameters being referred here are temperature, light, air-composition and the nature of rooting medium.

Indian horticulture has shown impressive impact on production, productivity and profitability. Currently, the total production of horticultural produce is 214.7 million tones from the 9% of total cultivated area in India, which contribute 30.4% to GDP of agriculture (Singh, 2010). In world perspective, India is second largest producer of fruits (68.5 mt) from 6.10 m ha area and contributes 11.2% in global fruit production. Vegetable crops occupying 8.0 m ha have the production of 129.1 mt (Table 1). However; India is the largest producer, consumer and exporter of spices and spice products in the world and produce more than 50 spices. The spice production in India is the order of 4.14 mt from an area of about 2.63 m ha. India is also the leading producer of plantation crops in the world and contributes 22.34% in coconut, 25% in cashewnut and 55% in arcanut. Commercial floriculture sector has recorded fast pace of growth during the last decade. During the last decade area under floriculture has expended to 1,67,000 ha with production of 9,87,000 MT of loose flower and 4.8 million cut flowers (Singh, 2010). The over all percent share of fruits and vegetables to their total production and contribution of different states for production of fruits and vegetables are repicted in Fig. 1 & 2. From the above fact, it is indicated that the production of horticulture produce has increased manifold but the gap in demand and supply continues simultaneously and is hardly sufficient and meets only 46% of national demand. Hence, there is a strong need to increase the production and productivity through crop diversification.

Agriculture in India is one of the most important sectors of its economy. It provides livelihood to almost two thirds of the work force in the country and accounts for 18% of India’s GDP. About 43 % of India’s geographical area is used for agricultural activity and large number of production systems are in practice in different parts ofthe country. In pre-independence era (before the 1950s), agriculture in India was a system of harnessing nature for the sustenance of human beings, similar to the presently defined organic farming. Some countries have moved away from inorganic to organic farming yet it is not possible for India to depend entirely upon this system of farming due to large population. Total availability of plant nutrients from organic sources is projected to be 7.75 million tonnes by 2025 (Tandon, 1997) against the total requirement of37.50 million tonnes (Katyal, 2001) for 1504 million population (Sekhon, 1997). Thus nutrients supply through organic sources alone would result in deficiency of about 30 million tonnes of nutrients. Hence, it is imperative to use both organic and inorganic sources of plant nutrients enhance food production for the increasing population (Mahajan et al., 2007). In India the contribution of organic sources was 80-100 per cent in 1949-50 and reduced to about 32 per cent in 1993-94 and 20-25 per cent in 2004-05. So, it is imperative to enhance organic sources to meet total nutrient consumption. Following independence, rapid population growth in India placed great pressure on land and on these traditional farming systems; huge demands for food grains led to increased use of fertilizers and pesticides to boost production. Still a negative balance of about 8 million tones of NPK is foreseen in 2020, even if we continue to use chemical fertilizers, maintaining present growth rates of production and consumption. The most optimistic estimates at present, show that only about 25-30 per cent nutrient needs of Indian agriculture can be met by utilizing various organic sources. Many of the gains in production during the last 4-5 decades resulted from the “Green Revolution,” a campaign of technological interventions in agriculture widely adopted by farmers in developing countries. Expansion of irrigation to cover rain fed areas, popularization of hybrids/ transgenic varieties of crops, and use ofsynthetic chemical fertilizers and pesticides were the maj or technologies promoted. This paid rich dividends in India, quadrupling food grain production from 50 million metric tons in 1950-51 to 211 million metric tons in 2001-02, and enabling India to become self-sufficient in food grain. Now a second green revolution is also in the offing, to boost agricultural production and meet the estimated requirement of 337 million metric tons.

Rice-wheat cropping system is the most important food production system in India. This system has enabled the country to attain food security during last three decades and provided livelihood to millions of farming families in recent times. The productivity of this system has now started showing signs of decline or stagnation at many places. There are also concerns of declining soil health and other related environmental problems. At the same time, food demand is rapidly increasing due to increasing population and income growth. During the past 30 years, agricultural production has been able to keep pace with population demand for food. This came about through significant area and yield growth. Area growth was a result of new lands being farmed and through increases in cropping intensity, from a single crop to double or even triple crops per calendar year. Area growth will be less important in its contribution to production growth in the future as more land is used for urban areas and industry. Yield growth will have to be the mainstay for providing the means for meeting future food demands unless food imports start to play a major role. Total factor productivity is declining and farmers have to apply more fertilizer to obtain the same yields. There is, therefore, a huge challenge ahead to meet future food demands without damaging the natural resource base on which agriculture depends, producing food at a cost that is affordable by the poor, and with incentives to farmers that allow them to improve their livelihoods. Water will become a major limiting factor for sustained production in the next decade. Rapidly growing urban areas and industry will compete with agriculture for good quality water. There are already reports of declining water tables in some areas leading to more costly pumping of groundwater and increased costs of production.

This chapter describes various conservation agriculture technologies to attain the goal of increasing productivity and meeting food security needs while at the same time efficiently using natural resources, including water, providing environmental benefits and improving the rural livelihoods of farmers. The major success in the last few years has been the development and deployment of conservation agriculture technologies (CATs) with farmers in the rice-wheat systems. CATs range from simple surface seeding, where wheat seed is broadcast on the non-ploughed soil; no-till with a special opener for placing seed in the soil also without ploughing; reduced tillage and bed planting. This has benefited farmers through less cost, more yields and more income. CATs are defined as any practice that will result in improvement of the efficiency of natural resources. These technologies are rapidly gaining popularity among farmers as they result in higher production at less cost with significant benefits to the environment and more efficient use of natural resources. This ultimately results in higher profits, cheaper food, and improved farmer livelihoods. Crop diversification is also easier as less land is needed to produce staple cereals, freeing up land for other crops.

Biodiversity is the variety of life in different microbes, animals, plants and their genes present in the ecosystem. Soil provides a vital habitat and environment primarily for microflora such as bactria, actinomycetes, fungi as well as microfauna viz. protozoa and nematodes, mesofauna such as microarthopods, enchytraeids, macrofauna such as earthworms, beetles, termites and millipedes (Gaur 2006a).

Biodiversity and soil are interlinked which interact closely with wider biosphere. Conversely, biological activity is ofprime importance in influencing the physical and chemical conditions of soil (Bardgett 2005). The level of soil biological activity is, therefore, affected by soil type and also depends on the use of management practices which contribute to crop productivity.

Soil biodiversity and soil processes

A majority of soil organisms participate in various processes which are essential for the biosphere. The main ecological function is to decompose organic matter largely derived from the plant and animals residues Which consist of celluloses, hemicelluloses and lignin, and to supply plant nutrients to support growth. These organisms participate in various nutrient cycles and processes such as nitrogen mineralization, nitrification, nitrogen fixation, transformations ofphosphorus, potassium, sulphur, calcium, magnesium, iron and micronutrients (Pankhurst et al 1997). They participate in bioremediation of harmful compounds such as heavy metals and pesticide residues (Gaur 2006 b). They not only maintain physical and chemical conditions of soil, but also regulate emissions / assimilations of green house gases and suppress soil borne diseases and pests

A nutrient budget is a valuable indicator of the long term sustainability of a cropping system. It indicates where fertilizer application is inadequate and leading to decline in the soil nutrient status. Conversely, it can indicate excessive inputs which result in a nutrient surplus and greater potential for losses to the environment and waterways. (Combs et al., 1996) Thus nutrient budget is the comparison between all the sources of nutrients available to the producer and the requirement of nutrients to meet the crop and soil needs. The sources can either be from on the farm, such as livestock manure or credits from legumes, or from off the farm, such as purchased fertilizer or irrigation water. The requirement is the amount of nutrients needed by the crop to obtain the expected yields.

Most values for nutrients available from different sources (credits) and crop nutrient requirements are calculated from estimates taken from many years of long historical averages and field research. There is no “real time” method of calculating exactly what neither the crop’s nutrient requirement or the nutrients available are at any one time. More closely, both the nutrient requirements and availability are based on past performance for the climatic and soil condition. These values are given with some surety that the crop grown will be supplied with adequate nutrient during the growing season and the crops will not be limited in its growth. All incidental environment losses, such as runoff and leaching, have been accounted for. Climatic conditions, particularly temperature and soil moisture, greatly influence both the crop performance and the soil’ s capacity to provide nutrients to the plant. During any growing season, there can be many changes in the climate conditions that will affect both the crop growth and soil delivery of nutrients to the crop.

Although a nutrient budget is not an exact formula for supplying nutrients, it is one method for organizing the nutrient needs ofthe crop with the nutrients available on the farm. Nutrient budgets can easily determine if there is a gross imbalance between the nutrients that are available vs. the amount required. Nutrient budgets are one of the best methods to see the over all supply of crop nutrients available, compared to the estimated crop needs as given by historic records and field research. Continued use of soil testing, plant and water analyses and yield monitoring are essential to maintain good nutrient balance with desired results.

Organic C in agricultural soils contributes positively to soil fertility, soil tilth, crop production, and overall soil sustainability. Changes in agricultural management can potentially increase the accumulation rate of soil organic Cd (SOC), thereby sequesteringCO₂fromtheatmosphere.Optimizingagricultural management for accumulation of SOC can result in the sequestration of atmospheric CO₂, thereby partially mitigating the current increase in atmospheric Carbon dioxide. In addition to the environmental benefits of soil C sequestration, Carbon dioxide consideration has also been given to the implementation of a C credit trading system which may provide economic incentives for C sequestration initiatives.

Changes in agricultural practices for the purpose of increasing SOC must either increase organic matter inputs to the soil, decrease’decomposition of soil organic matter (SOM) and oxidation of SOC, or a combination thereof. These practices include, but are not limited to, reducing tillage intensity, decreasing or ceasing the fallow period, using a winter cover crop, changing from monoculture to rotation cropping, or altering soil inputs to increase primary production (e.g., fertilizers, pesticides, and irrigation). Implementing practices that sequester C can reverse the loss of SOC that may have occurred under intensive cultivation thereby increasing SOC to a new equilibrium

Balanced crop nutrition is a most reaJized critical factor in allowing crops to give their full yield potential. The application of macro and micronutrients through manures and fertilizers to achieve this balance is an integral practice in modern crop production system. Macro and microelements have long been recognized as being associated with changes in the level of many diseases and yield and /or quality of crops. Three major elements N, P, and K are the most studied nutrients which chiefly affect relative resistance of crop plants to various diseases. Others macro/micro/beneficial nutrients including Ca, Mg, S, Mn,Te, Zn, Mo, Si, Bo and Cu have shown varying degrees of disease suppression/induction on many crop species under various environmental conditions. Crop nutrition influence plant health through: i. affecting the growth, reproduction, virulence, and survival of pathogens; ii. resistance and tolerance, predisposition and escape in the host crop; and iii. root exudates and microbial interactions facilitatingbiological control. Balanced crop nutrition can protect crops from pathogens by: i. avoiding plant stress, which may allow crops to better withstand the attack of pathogens and ii. manipulating nutrients to the advantage of crops and disadvantage of the pathogen. The modern intensive agriculture which mainly relies on chemical inputs (fertilizers and pesticides) and fertilizer responsive HYVs (high yielding varieties) has led the self sufficiency in food production in India and several other countries of the world. But, the indiscriminate and imbalance use of chemical fertilizers along with exhaustive cropping initiated several second generation problems including widespread micronutrient deficiencies and increased attack of several insect-pests and pathogenic diseases. The excessive use of nitrogen and no or reduced application of phosphorus, potash and other micronutrients is creating conducive conditions for several crop pathogens and their insect vectors. This situation frequently results in serious crop losses during favourable environmental conditions for disease development. The specific role of macro and micronutrients in maintaining crop health, effect of their dose and form of application on suppression /induction of various diseases and interaction with other soil/ environmental factor (s) will be discussed in following sections.

Cost is the value of the factors of production used in producing and distributing goods and services. The cost of a factor unit equals the maximum amount which the factor could earn in alternative employment. Broadly speaking, cost is the measure of what has to be given up in order to achieve something. Production costs play an important role in the decision of the farmers. Cost of production here means the exogenesis incurred per unit of output. In general, at given level of prices, a farmer can increase his farm income in two ways i.e. (i) by increasing production or (ii) by reducing the cost of production. The cost of production involves both cash cost and non cash cost items. Cash costs are incurred when resources are purchased and used immediately in the production process such as casual labour, fertilizer fuel etc. And non cash cost like depreciation on farm building and equipment and payment made to farmer himself or family labour, management and owned capital. Before estimating the cost of cultivation/production, we should know the concepts/terms are used in estimating the cost. Concept means idea underlying or general notion.

Cost concepts and items of cost

The cost of production of a crop is considered at three different levels viz., cost A, cost B and cost C. The concept of nine costs such as is followed by the Directorate of Economics and Statistics, Ministry of Agricultures Government of india in their cost studies are given below.

Introduction

Seed spices include group of annuals whose dried fruit or seeds are used as spices. These are characterised by pungency, strong odour, sweet or bitter taste. Coriander, cumin, fennel and fenugreek occupy largest area among the seed spices. However, ajowan, dil, celery, anise, nigella and caraway having secondary place as far as area and production is concerned. Major area under seed spices is in Rajasthan and Gujarat, and other seed spices producing states are Chattisgarh, Madhya Pradesh, Andhra Pradesh, Tamil Nadu and Uttar Pradesh. The seed spices account for about 36% and 17% of the total area and production of spices in country. The export of seed spices from India during 2008-09 was 4.71 thousand tonnes worth Rs. 54914.8 million rupees. The per cent export growth rate during 1995-96, 2000-01, 2005-06, 2007-08 and 2008-09 was 12.0, 11.0, 8.0, 36.0 and 19.0% in terms of value and 13.0, 3.0, 8, 13.0 and 6.0 in respect of quantity, respectively.

Integrated plant nutrient management includes use of organic manure/ compost, bio-fertilizer, chemical fertilizer, green manuring, residue management, legume based cropping system, use of nutrient-responsive varieties, proper method and time oforganic manure and fertilizer application, soil and water management to minimize the nutrient losses occurring through volatilization, denitrification, runoff and leaching. Application of plant nutrients in proper balance form is also a part of Integrated Plant Nutrient Management (IPNS) system. Supply of nutrients to seed spices in appropriate quantities and at the correct times is essential for economically and environmentally sustainable agriculture. Soil organic matter, crop residues and manures play a vital role in the supply of macro and micronutrients and the transformation between the various organic and inorganic forms often control availability, both for plant uptake and loss to the environment (Aishwath and Vashishtha, 2008; Lal, et al., 2009).

Agricultural systems are complex, and understanding this complexity requires systematic research under shrinking agricultural research resources. Field experimentation can only be used to investigate a very limited number of variables under a few site-specific conditions. The crop growth simulation models simulate crop growth, development and yield taking into account the effects of weather, genetics, soil water, carbon and nitrogen, planting, irrigation and fertilizer (e.g. Nitrogen, Phosphorus) management. Ofthe many factors that potentially affect the growth of plants, the two that are most responsive to management are water and nitrogen. It is therefore not surprising that most crop models include routines to handle responses to water and nitrogen. Less frequently do models attempt to describe limitations due to other soil constraints (Probert and Keating, 2000). In the context of integrated nutrient management, the performance of a crop model depends mainly on its ability to adequately describe the release of nutrients from diverse inputs and their uptake by the crop.

Origins and genesis of a crop simulation model

Crop simulation model approach was started near about 50 years ago, in early 1960s when early simple crop models were developed for estimation of transpiration and photosynthesis. The first step towards crop modeling was the development of simple models to estimate light interception and photosynthesis (Loomis and williams, 1963; De wit, 1965 and Duncan et al., 1967). There are many crop growth simulation models. Some are more generic in nature while others are built for specific purposes. Most of these models simulate crop growth and soil processes using daily time steps. All models are developed with some assumptions and hypotheses, and all have strengths, weaknesses and limitations for appropriate application. Well-known crop modelling groups across the world include IBSNAT/IFDC (International Benchmark Sites Network for Agro technology Transfer/International Fertilizer Development Centre) in USA, WAU/AB-DLO (Wageningen Agriculture University/Centre for Agro-biological Research) in the Netherlands, and APSRU (Agriculture Production Systems Research Unit) in Australia. The IBSNAT project was initiated in 1982, and over the past 20 years it has developed more than 15 models, including CERES (Crop Estimation through Resource and Environment Synthesis) Rice and CERES Wheat, which are available either as stand-alone models or within the DSSAT (Decision Support System for Agrotechnology Transfer) shell (Uehara and Tsuji, 1993).

Carbon is found in all living organisms and is the major building block for life on earth. It exists in many forms, predominantly as plant biomass, soil organic matter, and as the gas CO₂ in the atmosphere and dissolved in sea water. Carbon cycles globally among five distinct pools among which the largest oceanic poolis estimated at 38000 Pg (Pg= petagram =1x10¹⁵g=billion tonnes) and is increasingat the rate of 2.3 Pg C yr^-1 (Fig. 1). The geological C pool, comprising fossil fuels, is estimated at 4130 Pg, pedologic, estimated at 2500 Pg to 1m depth, atmospheric pool comprising 760 Pg of C with nearly all of it as CO₂, and the smallest among theglobal C pools is the biotic pool estimated at 560 Pg. The pedologic and biotic C pools together are called the terrestrial C pool estimated at approximately 2860 Pg.

Objective: To identify drought tolerant genotypes by PEG method in laboratory.

Background information:

Among different abiotic stresses, drought is considered to be most detrimental for agricultural production. A drought is a period of below-average precipitation in a given climatic region that results in prolonged shortages in water availability, whether atmospheric, surface water or ground water. A drought can last for several months or years. Drought has substantial impact on ecosystem and agricultural productivity.

Some plant species are better able to tolerate drought stress than others. Genetic variability for drought tolerance also exists within many plant species (Blum, et al. 1980). The efficient exploitation of that variability for crop improvement would be facilitated by a fast and accurate screening method for identifying drought tolerant genotypes (Clark and Mc Craig, 1982). Several methods utilizing seedlings to screen for drought tolerance have been developed using an osmoticum such as polyethylene glycol (PEG) (Singh, et al. 1984). The other synonyms of PEG are Poly ethylene oxide (PEO) and Poly oxyethylene (POE); these other chemicals depend on the molecular weight. Chemical structure of PEG may be written as H”(O”CH₂”CH₂)_n”OH (Kahovec, et al. 2002). PEG is used in certain abiotic stress experiments to produce high degree of osmotic pressure, normally in the order of 'tens of atmosphere' PEG produces osmotic pressure due to its flexible nature and water soluble polymer. PEG also makes certain specific interactions with bio-molecules. Due to above properties PEG is used as a specific chemical to produce osmotic pressure in several biochemical and bio-membrane related experiments. For some genotypes, the seedling response apparently is a good indicator of the plant's reaction to drought stress later in its life cycle. However, early screening of seed plants via seedlings tests must still be considered as a method for identifying genotypes that will tolerate drought stress in the vegetative stage (Andersen, et al. 1987).

Objective: To identify salt tolerant genotypes by Glycine Betaine (GB) method in laboratory.

Background information:

Salt or salinity is a biggest danger that causes reduction in crop productivity worldwide. Salinity reduces the germination percentage, plant vigour and ultimately loss in final crop yield. There are different physiological parameters that are affected by high level of salinity viz., oxidative stress, physical alteration of bio-membrane, nutritional imbalance, loss of cell division & cell expansion, water stress, genotoxicity and ion toxicity. Together, these effects reduce plant growth, development and survival. During the onset and development of salt stress within a plant, all the major processes such as photosynthesis, protein synthesis and energy and lipid metabolism are affected. During initial exposure to salinity, plants experience water stress, which in turn reduces leaf expansion (Petronia, et al. 2011).

The water-soluble compounds which, are low in molecular weight, accumulate at certain concentration known as “compatible solutes” or “osmolytes” is the common strategy adopted by many organisms to combat the abiotic stresses. Some common compatible solutes are betaines, sugars (mannitol, sorbitol and trehalose), polyols, polyamines and amino acid (proline). Their accumulation is favored under water-deficit or salt stress as they provide stress tolerance to cell without interfering cellular machinery. The tolerant or sensitive species show difference in the stress tolerance level based on levels of accumulation of these compounds during abiotic stress condition. Accumulation of osmolytes like glycinebetaine (GB) in cells is known to protect organisms against abiotic stresses via osmoregulation or osmoprotection. Other roles of GB like cellular macromolecule protection and ROS detoxification have been suggested as mechanisms responsible for abiotic stress tolerance. In addition, GB also influences expression of several endogenous genes in plants.

Objective: To estimate total protein in the plant sample by Folin-Lowry's method.

Background information:

Protein assay can be done to determine the level of protein in solution by the Folin-Lowry biochemical method. The concentration of protein leads to change in color of the solution and based on different color in different protein concentration solution the change in color may be digitized by colorimeter or spectrophotometer. This technique was developed by Oliver H. Lowry in the year 1940s. The tyrosine and trytophan amino acid residues in a protein sample produces purple or blue color in the absorption maxima at 660 nm by using Folin-Ciocalteau (having phosphate and sodium tungstate molybdate) chemical reagent. The color intensity of protein sample depends on the concentration of above aromatic amino acids (tyrosine and tryptophan), hence every sample will vary for color. For protein estimation the BSA (Bovine serum albumin) is widely used as standard protein molecule due to its cost effectiveness, purity and easy availability. This method of protein estimation is very sensitive and can detect up to 10 μg/ml. This is a relative method of protein estimation and may be interfere by salts, Tris buffer, nonionic & cationic detergents, EDTA, lipids and carbohydrates. For reproducible assay the incubation time, pH (9-10.5) is critical in this method (Lowry, et al. 1951).

Objective: To separate protein fragments by using SDS-PAGE method.

Background information

Electrophoresis is the motion of dispersed particles relative to a fluid under the effect of limited uniform field of electricity (Dukhin, and Derjaguin, 1974). Ferdin and Frederic Reuss (Reuss, 1809) first time observed such phenomena of electrokinetic nature in 1807. They found that the clay particles move in the water by giving constant supply of current. It happened due to interface of charged particles surface and the surrounding media. The technique is used widely in chemistry, biochemistry and molecular biology to separate different molecules based on difference in charge, binding affinity and size. Electrophoresis may be of two types viz., Anaphoresis and Cataphoresis. Anaphoresis is the electrophoresis of anions (-ve charged ions) while, Cataphoresis is electrophoresis of cations (+ve charged ions). Electrophoresis is a major analytical technique in biochemistry that is used for separation of macromolecules like protein, enzymes and nucleic acids. Electrophoresis is a technique used in laboratories in order to separate macromolecules based on size.

PAGE is abbreviated for Polyacrylamide gel electrophoresis that describes a technique widely used in biochemistry, forensics, genetics, molecular biology and biotechnology to separate biological macromolecules, usually proteins or nucleic acids, according to their electrophoretic mobility. Mobility is a function of the length, conformation and charge of the molecule.

Objective: To extract and perform enzyme assay of polyphenol oxidase from plant.

Background information:

Polyphenol oxidase (PPO or monophenol monooxygenase or polyphenol oxidase I, chloroplastic) is a tetramer that contains four atoms of copper per molecule, and binding sites for two aromatic compounds and oxygen (www.worthington-biochem.com). The enzyme catalyses the o-hydroxylation of monophenol molecules in which the benzene ring contains a single hydroxyl substituent to o-diphenols (phenol molecules containing two hydroxyl substituents). It can also further catalyse the oxidation of o-diphenols to produce o-quinones.

PPO causes the rapid polymerization of o-quinones to produce black, brown or red pigments (polyphenols) that cause fruit browning. The amino acid tyrosine contains a single phenolic ring that may be oxidised by the action of PPOs to form o-quinone. Hence, PPOs are some time referred as tyrosinases (Mayer, 2006).

Jolley et al. (1974) referred to PPO as 4 electron-transferring phenol oxidase and oxygen. It is responsible for browning reactions throughout the phylogenetic scale.

Objective: To extract and perform enzyme assay of catalase from plant.

Background information

Catalase is a commonly distributed enzyme and present in approximately all organisms exposed to oxygen (such as bacteria, plants and animals). Catalysis of H₂O₂ into H₂O and O₂ is done by catalase enzyme (Goodsell, 2004).

Objective: To extract and perform enzyme assay of guaiacol peroxidase from plant.

Background information:

Peroxidases are a large family of enzymes that typically catalyze a reaction of the form:

Objective: To extract and perform enzyme assay of Superoxide dismutase from plant.

Background information:

Superoxide dismutase (SOD, EC 1.15.1.1) is the enzyme that alternately catalyzes the dismutation (or partitioning) of the superoxide (O₂^-) radical into either ordinary molecular oxygen (O₂) or hydrogen peroxide (H₂O₂). Superoxide is produced as a by-product of oxygen metabolism and, if not regulated, may cause cell damage (Hayyan, et al. 2016). Hydrogen peroxide is also responsible for cell damage and may be degraded by other enzymes like catalase. Thus, SOD is an important antioxidant defense in nearly all living cells exposed to oxygen. One exception is Lactobacillus plantarum and related lactobacilli, which use a different mechanism to prevent damage from reactive O₂^-.

Objective: To study peroxidase isozyme variation in rice seedlings by electrophoresis.

Background information

For electrophoresis and PAGE please see practical no. 4. For peroxidase please see practical no. 7.(Page 17-22)

Isozymes (isoenzymes or more generally as multiple forms of enzymes) are the enzymes that are differing in the sequence of amino acids but they work on same substrate or in other words catalyze same biochemical reaction. The isozymes have difference in K_M values and regulatory properties. Isozymes are very useful for proper tuning of metabolic activities and to meet the specific need of particular tissue or developmental stage, e.g. lactate dehydrogenase (LDH). Isozymes are coded by homologous genes that have diversity during evolutionary process. Although, strictly speaking, allozymes represent enzymes from different alleles of the same gene, and isozymes represent enzymes from different genes that process or catalyse the same reaction, the two words are usually used interchangeably.

Objective: To isolate DNA from plant sample by CTAB method and quantification by spectrophotometer.

Background information:

DNA isolation from different plant tissues viz., leaf, stem, root, flower and seed is a challenging task due to hindrance of variety of variety of biochemical compounds present and further problem increases with diverge plant species. In case of animal tissues the diversity in cellular bio-molecules in different species is much lower compared to plants. Two major phyto bio-molecules that have wide variation between species and pose serious problems in DNA isolation are: polyphenols and polysaccharides. These phyto bio-molecules if contaminated in DNA then may hinder further down applications like PCR, restriction digestion, sequencing, etc.

Several methods have been developed and reported that can remove polyphenols and polysaccharides efficiently during DNA isolation from plants. For this purpose two different chemicals are widely used,the first one is CTAB (cetyl trimethyl ammonium bromide) that is a cationic detergent and helps in removal of polysaccharides and the second one is polyvinylpyrrolidone that helps in removal of polyphenols. Due to above properties the CTAB based DNA extraction buffer is very common for plant DNA extraction.

Significance of different types of chemicals found in CTAB based plant DNA extraction method is explained as under:

Objective: To check quality of genomic DNA on agarose gel electrophoresis.

Background information

Agarose gel electrophoresis is a common method of gel based electrophoresis technique used in biochemistry, molecular biology, genetics and clinical chemistry for separation of Protein and nucleic acids from a mixture of macromolecules. Agarose is a major component of agar that is used as a matrix in gel baseelectrophoresis. The nucleic acids (DNA and RNA) are separated based on length of fragments while, proteins are separated based on size and/or charge (Kryndushkin, et al. 2003). For separation of bio-molecules the electric field is applied that leads to movement of charged particles via agarose gel matrix and bio-molecul s are separated based on difference in size in the agarose gel matrix (Sambrook and Russel, 2001).

Gel casting with agarose is easy and has very few charged groups, hence found most suitable for nucleic acid separation in most of the biochemistry, molecular biology and biotechnology laboratories. Separated DNA/RNA ma be seen and recorded with stain under UV light. Further DNA fragments can be eluted from agarose gel with an ease for further down applications. The percentage of agarose gel used is in the range of 0.7 - 2. Lower percent of agarose gel is used for long DNA fragments while, higher percent of agarose gel is used for short DNA fragments with suitable running buffer.

Objective: To amplify DNA using RAPD primers and study on agarose gel.

Background information:

RAPD markers are decamer (10 nucleotide length) DNA fragments from PCR amplification of random segments of genomic DNA with single primer of arbitrary nucleotide sequence and which are able to differentiate between genetically distinct individuals. RAPD is applied to analyze the genetic diversity by random primers. Unlike traditional PCR analysis, RAPD does not require any prior DNA sequence information of the target organism: the identical 10-mer primers will or will not amplify a segment of DNA, depending on positions complementary with primers' sequence. For example, no fragment is produced if primers annealed too far apart or 3' ends of the primers are not facing each other. Therefore, if a mutation has occurred in the templ that was earlier complementary with primer, a PCR product will not be produced, resulting in a different pattern of amplified DNA segments on the gel. RAPD is a dominant marker means it cannot distinguish between heterozygous; single copy and homozygous; two copies. Rarely RAPD markers may be Co-dominant where different fragment length of DNA is amplified from the single locus. PCR is a molecular technique used for amplification of DNA, a complete enzyme based chemical reaction, therefore, the concentration and quality of template DNA, concentrations of PCR components, and the PCR cycling conditions may greatly influence the outcome. Thus, the RAPD technique is notoriously laboratory dependent and needs carefully developed laboratory protocols to be reproducible. Mismatches between the primer and the template may result in the total absence of PCR product or decreased amplified product. Thus, the RAPD results can be difficult to interpret.

Objective:To transfer DNA on nylon membrane by Southern blotting.

Background information

A Southern blot is a method used in molecular biology to detect a specific DNA sequence in DNA samples. Southern blotting combines transfer of electrophoresis-separated DNA fragments to a filter membrane and subsequent fragment detection by probe hybridization.

The British biologist Edwin Southern (Southern, 1975) discovered this technique the technique is known by his name. Southern blotting technique uses digested genomic DNA with restriction enzymes. Southern blotting technique may be used to identify the gene copies number in a genome. A probe that hybridizes only to a single DNA segment that is uncut with restriction enzyme will produce a single band on a Southern blot, whereas multiple bands will likely be observed when the probe hybridizes to several highly similar sequences (e.g., may be due to sequence duplication).

In the southern blotting technique a short DNA probe is used that matches based on complementary DNA sequence fragment on filter membrane. It proves that the DNA fragment on membrane contain specific sequence for which DNA probe is prepared. When DNA is transferred on the membrane from gel it permits binding of radioactive/Biotin labeled hybridization probe to the restricted DNA. Southern blotting is also important for autoradiography.

Southern blotting is an important molecular biology technique that may be used for homology based cloning, screening a DNA library, screening of cloned DNA fragments and to identify methylated sites in genes.

Objective: To isolate RNA from plants using TRIzol reagent and its quantification by spectrophotometer.

Background information

RNA (Ribonucleic acid) is a polymeric substance present in living cells and many viruses, consisting of a long single-stranded chain of phosphate and ribose units with the nitrogen bases adenine, guanine, cytosine, and uracil, which are bonded to the ribose sugar. RNA is necessary in all the steps of protein synthesis in all living cells and carries the genetic information for many viruses.

The isolation of RNA with high quality is a crucial step required to perform various molecular biology experiment. TRIzol Reagent is a ready-to-use reagent used for RNA isolation from cells and tissues (Chomczynski, 1993).TRIzol works by maintaining RNA integrity during tissue homogenization, while at the same time disrupting and breaking down cells and cell components. Addition of chloroform, after the centrifugation, separates the solution into aqueous and organic phases. Aqueous phase contains RNA.

After transferring the aqueous phase, RNA can be recovered by precipitation with isopropyl alcohol. DNA and proteins can be recovered by sequential separation after the removal of aqueous phase. Ethanol precipitation needs DNA from the interphase, and an additional precipitation with isopropyl alcohol requires proteins from the organic phase. Total RNA extracted by TRIzol Reagent is free from the contamination of protein and DNA The isolated RNA can be further used in Northern blot analysis, in vitro translation, poly (A) selection, RNase protection assay and molecular cloning.

Objective: To check the integrity of isolated RNA on agarose gel.

Background information:

The most common method used to assess the integrity of total RNA is to run RNA sample on agarose gel (denaturing) stained with ethidium bromide (EtBr). While native (non-denaturing) gels can be used, the results can be difficult to interpret. The secondary structure of RNA alters its migration pattern in nativegels so that it will not migrate according to its true size. Nondenaturing conditions also result in bands that are not as sharp, and even multiple bands representing different structures of a single RNA species.

Intact total RNA run on a denaturing gel will have sharp, clear 28S and 18S rRNA bands (eukaryotic samples). The 28S rRNA band should be approximately twice as intense as the 18S rRNA band. This 2:1 ratio (28S:18S) is a good indication that the RNA is completely intact. Partially degraded RNA will have a smeared appearance, will lack the sharp rRNA bands, or will not exhibit the 2:1 ratio of high quality RNA. Completely degraded RNA will appear as a smear (having very low mw). Inclusion of RNA size markers on the gel will determine the band size or smears size and will also serve as a good control for ensuring proper gel run. Note: Poly selected samples will not contain strong rRNA bands and will appear as a smear from approximately 6 kb to 0.5 kb (resulting from the population of mRNAs, and depending on exposure times and conditions), with the area between 1.5 and 2 kb being the most intense (this smear is sometimes apparent in total RNA samples as well).

Objective: To synthesize cDNA from isolated plant total RNA.

Background information:

Complementary DNA (cDNA) is double-stranded DNA made from template of single stranded RNA, [e.g., mRNA or microRNA] by reverse transcriptase enzyme. Mostly cDNA is used for cloning of eukaryotic genes in the prokaryotes. For the expression of a specific protein in a cell where the expression of that protein is not found (i.e., heterologous expression), the cDNA will be transferred that codes for the protein to the recipient cells. Retroviruses (e.g. HIV-1, HIV-2, simian immunodeficiency virus, etc.) also produce cDNA naturally and integrate in host's genome and further creates provirus (Croy, 1998). Major use of cDNA is in gene cloning or as gene probes or in the creation of a cDNA library. When scientists transfer a gene from one cell into another cell for the expression of new genetic material as a protein in the recipient cell, the cDNA will be added to the recipient (rather than the entire gene), because the DNA for an entire gene may have certain DNA that may not code for the protein or that interrupts the coding sequences of the protein (e.g., introns). Partial sequences of cDNAs are often obtained as expressed sequence tags.

Objective: To quantify aflatoxin content in given sample by Indirect competitive ELIS

Background information:

Enzyme linked immuno sorbent assay (ELISA) is a common biochemical technique that uses the principle of solid-phase enzyme immunoassay (EIA) for detection of substances mainly antigens in a liquid or wet sample.

ELISA is a very popular technique that is used for diagnostic purpose in health sector, plant protection and also for quality test in food and other industries. This technique applies the principle of antigen-antibody reaction on a solid surface. The attached antibody is linked to certain enzymes and in the end of reaction by addition of substrate that performs enzyme-substrate reaction and makes product that has some signal mostly color change and based on intensity of color the qualitative as well as quantitative estimation of antigens can be done using ELISA reader coupled with spectrophotometer.

In ELISA technique one antibody should be specific to certain antigen. For reaction of ELISA the ELISA plates are used that is also known as microtiter plate made-up of polystyrene. The sample to be tested for ELISA contain unknown amount of antigen to be detected, this sample containing antigen is immobiliz d on a solid support like polystyrene microtiter plate in two different ways; first is non-specific where antigens adsorbed to the surface and second is specific where the antigens of sample are captured by specific antibody to the antigen, like used in sandwich ELIS Once the antigens are immobilized non-specifically or specifically the detection antibody should be added that makes precise antigen-antibody complex. The detection antibody may be either covalently linked to certain enzyme or may be detected by another secondary antibody linked to bioconjugated enzyme. During ELISA steps several proteins or antibodies may non-specifically bound that can be removed by washing with mild detergent solution in between of each ELISA step. For washing of ELISA plates, ELISA plate washer may be used that mechanically wash the ELISA plates. At the end of ELISA the final wash is given and substrate is added that produces visible signal in the form of color change that indicates the presence of antigens in the sample and further quantification may be done using ELISA reader coupled with spectrophotometer.