eChapters

Organic agriculture or farming is very much native to India. Whosoever tries to write a history of organic farming will have to refer India and China. The farmers of these two countries are farmers of 40 centuries and it is organic farming that sustained them. This concept of organic farming is based on following principles:

• Nature is the best role model for farming, since it does not use any inputs nor demand unreasonable quantities of water.
• The entire system is based on intimate understanding of nature’s ways. The system does not believe in mining of the soil of its nutrients and do not degrade it in any way for today’s needs.
• The soil in this system is a living entity.
• The soil’s living population of microbes and other organisms are significant contributors to its fertility on a sustained basis and must be protected and nurtured at all cost.
• The total environment of the soil, from soil structure to soil cover is more important.

A dilute solution of acetic acid produced by a two-stage fermentation process in the first stage, fermentable sugars is converted into ethanol by the action of yeasts and in the second stage, bacteria of the genus Acetobacter oxidize the ethanol to acetic acid.

Vinegar is a liquid produced from the fermentation of ethanol in a process that yields its key ingredient, acetic acid. The acetic acid concentration ranges typically from 4 to 8 percent by volume for table vinegar (typically 5%) and higher concentrations for pickling (up to 18%). Natural vinegars also contain smaller amounts of tartaric acid, citric acid, and other acids.

Fruit juices which do not undergo alcoholic fermentation are termed as unfermented beverages. They include natural and sweetened juices, RTS, nectar, cordial, squash, crush, syrup, fruit juice concentrate and fruit juice powder. Barley waters and carbonated beverages are also included in this group.

Fermentation in food processing typically is the conversion of carbohydrates to alcohols and carbon dioxide or organic acids using yeasts, bacteria, or a combination thereof, under anaerobic conditions.

Introduction

Development of improved crop varieties is vital for sustained increase in agriculture production and productivity. Timely supply of quality seed is equally significant since the contribution of quality seed alone is estimated to be 15-20 per cent to total crop production. Seed quality attains more significance in view of emerging biotic and abiotic stresses, issues related to quality and phytosanitary measures, competition in domestic and international markets and emerging food needs. Measures of seed legislation with respect to quantity and quality were initiated in the country by establishment of National Seed Corporation during 1963 under Ministry of Agriculture. The seed sector in India during the period was dominated by the Public sector. The National Seed Corporation was the Central Body to produce seeds of superior dwarf varieties in rice, wheat, and superior hybrids in maize, pearl millet and sorghum. This was followed by various seed legislations enacted by Government of India. Further, AICRP-NSP (Crops), popularly known as National Seed Project was launched during 1979-80. The NSP-Project came into operation in three major phases and continues to produce breeder seed to cater the needs of the Indian farmers. The project resulted in achieving breeder seed production surpassing the indents in all major crops. The seed programme of the country was further strengthened with NSP II (World Bank) Project starting in 1989-90, which not only supported the ICAR and SAUs, but also Department of Agriculture, Seeds Corporations, Seed Certification Agencies and Private Seed Industries to a great extent in production, processing and in providing quality seeds to the country.

Freezing is one of the easiest and least time consuming methods of food preservation. The freezing process is a combination of the beneficial effects of low temperatures at which microorganisms cannot grow, chemical reactions are reduced, and cellular metabolic reactions are delayed.

Methods of Freezing

1. Sharp freezing (slew freezing)

In sharp freezing commodities are exposed at -15 to -29⁰C. It required 3-72 hrs. Here the thawed tissue cannot regain its original water content. The ice crystals formed are large and rupture the cells. The thawed tissue cannot regain its original H₂O content.

Removal of water from the food by non-conventional energy source like sunlight, wind, and a smoky fire. Drying (dehydrating) food is one of the oldest and easiest methods of food preservation.

Dehydration

Dehydration is the process of removing water or moisture from a food product under controlled condition like temperature, relative humidity, air flow, etc.

Principles of Drying and Dehydration

Drying removes the moisture from the food so that bacteria, yeasts and moulds cannot grow and spoil the food. It also slows down the action of enzymes, but does not inactivate them. Dried food items can be kept almost indefinitely, as long as they are not rehydrated.

Introduction

In order to implement the sui generis system for plant variety protection for granting PBR to a breeder or farmer or institution, DUS testing is compulsory. A new variety shall be registered, if it conforms to the criteria of novelty, distinctness, uniformity and stability. An extant variety, a variety about which there is a common knowledge shall also be registered within a specified period, if it conform such criteria as distinctness, uniformity and stability.

Once a valid application for PBR is accepted the seed / plant material of the variety will be requested for official DUS tests. These official DUS tests need to be conducted by crop based institutions on behalf of the PPV & FR authority by following universally acceptable test procedures. This necessitated in the development of test guidelines, descriptors and procedures to be followed in each crop. National Test Guidelines have been developed for 96 crops representing harmonized approach for the testing of new varieties which will form the basis for DUS examination. These National Test Guidelines contain details on i) subject of the guidelines, ii) material required, iii) conduct of tests, iv) methods and observations, v) grouping of varieties, vi) characteristics and symbols, vii) table of characteristics, viii) explanations on table of characteristics, ix) literature and x) technical questionnaire. The registration was open for 107 crop species for new variety and for 114 crop species for extant / farmers varieties.

Canning is a process of sealing food stuffs hermatically in containers and sterilizing them by heat for long storage is known as canning.

Principle of Canning

Destruction of spoilage organism within the sealed container by means of heat.

Selection of Fruit and Vegetable

For canning fruit should be ripe but firm and uniformity mature and vegetables except tomato should be tender.

Grading

Selected fruit and vegetable are graded according to size and colour to obtain uniform quality. This is done by hand or machines such as screw grader and roller grader.

Food additive is any chemical substance that is added to food during preparation or storage. A food additive either becomes a part of the food or affects its characteristics for achieving a particular effect. For instance, substances that are used to enhance the appearance, texture, or to keep qualities of a food are considered food additives.

Preservation means just protect the foods against the spoilage, but scientifically it may be defined as a science which deals with the process for prevention of decay or spoilage of the food is called preservation.

In other words, just controlling the physical, chemical or microbial changes in the foods is called preservation.

Physical Changes: Colour, flavour, texture and taste etc.

Chemical Changes: Carbohydrate, fats, proteins, vitamins and minerals.

Microbial Changes: Mould, yeasts and bacteria

Introduction

Seed is a critical and vital input that draws an explicit line between the success and failure of any agricultural production programme. In fact progressive history of agriculture has been a history of seed development and production. The mankind has been attempting to select better seed and employ better seed production techniques volitionally or in-volitionally ever since it divested nomadic life for the settled one. Initial attempts were confined to selection of useful crops followed by selection of better sorts and land races among the available native genetic resources. The introductions, hybridization followed by selection of better types and modern breeding tools inclusive biotechnological interventions have been extensively employed to breed better seed. Considering that research in crop improvement can turn little stone unless the quality seed with desired attributes is made available to the farmers. Government of India set up enforcement of provisions of Seed Act, 1966 for certification of seed as per prescribed minimum standards. Central Seed Certification Board was established in 1972 to exhort the central and state governments for producing genetically and physically pure and physiologically viable seed. The seed production programmes and rules were progressively honed to meet the ground situations. Initially the seed was considered as the exclusive bastion of public sector but the private sector got actively involved in seed production. WTO the seed still became a very open subject and the Seed Act was modified in 1988 and 2001 to permit import and export of quality seed, respectively. Despite of all these positive developments in seed sector, the availability of seed is still far from satisfactory. As on today private sector dabbles in low volume high cost seed due to economics and storage factors but the high volume less cost is still a virgin for private sector and is predominantly done by the public sector. Crop improvement is no more an art and science of improving hereditary of crop plants but has become a starker and competitive business under which the stronger would survive and the weaker get eliminated.

Business was abysmally shattered at the terminal end of the Second World War. This forced some nations to sign some tariff related global

Physiological disorders refer to non-parasitic or inanimate disease of fruit crops, or it is the breakdown of tissue that is not caused by either invasion by pathogens or by mechanical damage. They may develop in response to an adverse environment, especially temperature or to a nutritional deficiency during growth and development. Physiological disorder is broadly classified into two broad categories. They are:

Packaging is an important consideration in vegetable and fruit market. The use of properly designed containers for transporting and marketing of vegetables is significantly reduce losses and maintain their freshness succulence and quality for longer period. Packaging also provides protection from mechanical damage and undesirable physiological changes and pathological deterioration during storage, transportation and marketing.

Many vegetables are transported in gunny bags and bamboo baskets. Packaging material such as polythene films, paper boars, and boxes lived with polythene and other materials can effectively prolong the shelf life of vegetables. By using plastic films vegetables can be protected from dry air. Polythene packaging provides modified atmosphere and consequently reduces decay, softening, and loss of solids. The thickness and permeability to CO₂, O₂ and water vapour of films needs to be standardized for each vegetable.

Introduction

Stored-product insects are serious pests of dried, stored, durable agricultural commodities and of many value-added food products and non-food derivatives of agricultural products worldwide. Various estimates on post harvest losses across the country revealed that there is loss of 2–12 per cent during storage exclusively by insects. Almost all the insect species may destroy 10.0 -15.0 per cent of grain and contaminate the rest with undesirable odour. The major loss is done by two internal feeders i.e. rice weevil and grain borer, which are major pests of rice, wheat and millets (Champ and Dyte, 1977). They also help in transportation of fungi (Sinha and Sinha, 1990). The losses during storage are quantity losses and quality losses. Quantity losses occur when insects, rodents, mites, birds and microorganisms, consume the grain. Infestation causes reduction in seed germination, increase in moisture, free fatty acid levels and decrease in pH and protein contents etc. resulting in total quality loss. Quality losses affect the economic value of the food grains fetching low prices to farmers (Das et al., 2013).

Proper marketing of perishable commodities such as fruit and vegetables often requires some storage to balance day-to-day fluctuation between harvest and sale or for long term storage. Storage of horticulture produce is attempeted with a view to extend period of availability. Storage controls shelf life of produce by controlling rate of respiration, transpiration, ripening and biochemical changes all of which are responsible for shelf decomposition/deterioration of produce. Further, different types of storage have different attributes in minimizing microbial infection and thus add to better storability of produce.

It is a most deteriorating biological process of the harvested fruits and vegetables that leads to the oxidative breakdown of the complex material (carbohydrates or acids) of cell into simpler molecules (CO₂ & water) with production of energy. Respiration includes glycolysis metabolism, aerobic metabolism, anaerobic metabolism, trycarboxilic acid cycle and electron transport metabolism processes.

Ethylene (C₂H₄ also known as ethene) is a gaseous organic compound that is the simplest of the alkenes chemical structures (alkenes contain a carbon-carbon double bond). The hormone effects of ethylene on general plant growth were first noted in 1864 when leakage from gas street lighting systems caused stunting and deformation of nearby plants. In 1901 Neljubow identified the active component of the gas to be ethylene but it was not until 1934 that Gane identified that plants could synthesize ethylene and in 1935 Crocker proposed ethylene to be the hormone responsible for fruit ripening and senescence of vegetative tissues.

Ethylene play important role in many plant during development processes, including seed germination, vegetative growth, leaf abscission, flowering, senescence and fruit ripening. Ethylene also plays a role in response to water stress, chilling and mechanical injury.

Ripe

This word is derived from Saxon word ‘Ripi’, which means gather or reap. This is the condition of maximum edible quality attained by the fruit following harvest. Only fruit which becomes mature before harvest can become ripe.

Ripening

Ripening involves a series of changes occurring during early stages of senescence of fruits in which structure and composition of unripe fruit is so altered that it becomes acceptable to eat. Ripening is a complex physiological process resulting in softening, colouring, sweetening and increases in aroma compounds so that ripening fruits are ready to eat or process. The associated physiological or biochemical changes are increased rate of respiration and ethylene production, loss of chlorophyll and continued expansion of cells and conversion of complex metabolities into simple molecules.

Since time immemorial, spices have played a vital role in world food trade, due to their varied properties and applications. We primarily depend on spices for flavour and fragrance as well as colour, preservative, inherent therapeutic, medicinal and appetizing properties. The spices that India can offer in abundant quantities are pepper, ginger, turmeric, chili, cardamom, celery, fenugreek, fennel, cumin, dill, coriander, cinnamon, ajowan, cloves, nutmeg, mace etc.

Flowers are highly perishable unlike other horticultural or agricultural crops. Owing to poor keeping quality the post harvest losses in floriculture are significantly higher than any other sector. Although there has been significant increase in the area, production and productivity of flower crops in the last two decades, there is an urgent need to minimize the huge post harvest losses in terms of the value of the produce which are estimated to be 30-40 per cent of farm value. The post harvest behavior of flowers is an outcome of the physiological processes, occurring in leave, stem, flower bud, leafless peduncle or scape connecting bud to the stem. Some of these processes may act independently to affect the senescence and vase life of cut flowers but most of them are inter-related. The nature and extent of post harvest damage is typical for each crop or cultivar. The post harvest losses become important especially when dealing with the export of fresh flowers to distant and foreign market. Therefore, patient, soft and expert handling of flowers is of utmost importance after harvest.

Fruits and vegetables are living tissues subject to continuous change after harvest. Some changes are desirable from consumer point of view but most are not. Post-harvest changes in fresh fruit cannot be stopped, but these can be slowed down within certain limits to enhance the shelf life of fruits. The post-harvest handling plays an important role in extending the storage and marketable life of horticultural perishables.

Post Harvest Treat ment of Fruits and Vegetables Washing

It is useful in removing surface adhering material water. Mechanically, it is also accomplished by passing the fruits/vegetables through machine arranged with water tank equipped with rotating brush. In some produce washing improves appeal by facilitating removal of sap as case in mango, papaya, jackfruit, kronda, dirt in case of carrot, reddish, turnip, sugar beet, sweet potato, etc. and for removal of debris in case of banana. The water use for the purpose should be cleaned otherwise fungal and bacterial levels may build up. Disinfected treatment using ultraviolet light, ozone, chlorine (100 ppm), calcium hydroxide, etc. help to clean water for washing purpose.

Maturity

It is derived from Latin word ‘Maturus’ which means ripen. It is that stage of fruit development, which ensures attainment of maximum edible quality at the completion of ripening process.

Maturation

It is the developmental process by which the fruit attains maturity. It is the transient phase of development from near completion of physical growth to attainment of physiological maturity. There are different stages of maturation e.g. immature, mature, optimally mature, over mature.

Maturity Indices

The factors for determining the harvesting of horticulture commodities according to consumer purpose and type of commodity.

Maturity Indices is two type

Fruits and vegetables are important part of our dietary, which are rich source of nutrient (carbohydrates, protein, fat, vitamins, minerals, and dietary fiber). Carbohydrates, protein and fat are macronutrients, considered as energy sources. Vitamins and minerals are micro nutrient, play important role in body building. Fibers have several direct and indirect advantages. ICMR, New Delhi recommends 125g of leafy vegetables, 100g of root and tuber vegetables and 75g of other vegetables (total 300g/day) and 85g of fruits per capita every day for balance diet.

India is a second largest producer of fruits and vegetables after China. These share are 10% and 16% respectively in total world production. Horticulture crops occupy 23.548 million ha and production is estimated around 260.063 million tones. Total area of fruits, vegetable, plantation crops, spices, loose flower and aromatic plant are 7012, 9083, 3606, 3092, 218 and 537 thousand ha, respectively and production are 79400, 156445, 16388, 5786, 1421 and 622 thousand tones, respectively with productivity are11.32, 17.22, 4.54, 1.87, 6.59, 1.19 thousand tones per ha, respectively (2012-2013). The total productions of cut flowers are 74305 Lakh stem (2012-2013). The annual horticulture export volume is 2733145 metric tonnes (2010-2011) with total exported value of Rs 696461 lakh. In terms of volume, fresh fruits & vegetables comprised about 76 % of exported horticulture produce followed by processed fruits & vegetables (23 %) and floriculture & seeds (1%). After that losses found 20-30 % in fruit and 30-40 % in vegetable while harvesting to consumption in India. It’s due to the perishable nature of horticulture commodity, non availability of appropriate post harvest infrastructure transportation, inadequacy of the market or lack of processing.

India is a major horticulture producer, even though processing is less than 2 %. This is very low as compare to 80 % of Malaysia, 78 % of Philippine, 70 % of Brazil and 30 % of Thailand. The most of developed country 40-60 % fruits and vegetables utilize in processing.

Proper handling, packaging, transportation and storage reduce the post harvest losses of fruits and vegetables. For every one percent reduction in loss will save 5 million tons of fruit and vegetable per year. Processing and preservation technology helps to save excess fruit and vegetable during the glut season. The technology has become a necessity to improve the food safety and strengthen nations food security. The technology helps to boost export of agricultural commodities in the form of preserved and value added products.

5.1 The Need

In spite of the considerable experience and quite a few facilities available in the country, the growth of application of isotope techniques is not commensurate with India’s size, its climatic and hydrogeological diversity and the sheer range of its water resources problems.

The situation may not be unique to India and other developing countries. Australia also appears to be facing a similar problem. A recent publication [1] says ‘the limited uptake of the method may be due to a number of factors. Until relatively recently, isotope hydrology has remained a largely academic pursuit, or measurements were the domain of national atomic energy agencies. A large fraction of information lies buried in the grey literature or in arcane technical journals. Interaction with local or regional water resources agencies has been the exception rather than the rule’

India has probably a stronger case for a more effective use of isotope techniques. A large portion of groundwater occurs in hard rocks in India. Normal hydrogeological and geophysical methods cannot fully describe such groundwater regimes to effectively plan their exploitation. It is essential to apply tracer hydrology methods, especially isotope geochemical techniques, for a comprehensive understanding of the systems. The examples of Manikaran geothermal springs, seepage studies in Salal tunnel and in some dams, given in the earlier chapters come under this category. Studies on percolation tanks in basaltic terrain and on recharge processes need isotope support.

It will not be long before we would be planning to exploit very deep ground waters (>500 m), both in the hard rock terrains of peninsular India as well as in the Ganga plains to meet our ever growing need for water. We would need good understanding of the recharge processes to these deep ground waters. Isotopes will have a large role in such investigations.

Arid zone hydrology is yet another area where the potential of isotope techniques has been effectively demonstrated for the characterization of the recharge processes, both palaeo and modern, and including the role of ancient rivers.

After precipitation, run-off and surface water storage in lakes and man-made reservoirs, the next steps in the hydrological cycle are infiltration through the unsaturated zone and groundwater dynamics in the saturated zone. Well-established applications of isotopes in groundwater hydrology are

The range of isotope applications in surface water hydrology is not as wide as in groundwater hydrology as the surface waters are more easily amenable to conventional hydrological methods. Following are the areas in which isotopes have a significant role in either improving the accuracy of measurements or in providing additional information, which is otherwise not easily available.

In the last chapter, we have broadly introduced the concept of tracer hydrology and also the concepts of isotopes as tracers, their characteristics and measurement techniques. In this chapter let us see the basis of application of each group of isotope tracers, injected and environmental.

What are the different groups of isotope tracers used in hydrology and how are they classified?

“Hydrology is the science that treats the waters of the earth, their occurrence, circulation and distribution, their chemical and physical properties, and their reaction with their environment, including their relation with living things. The domain of hydrology embraces the full life history of water on the earth.” (Federal Council for Science and Technology, “Scientific Hydrology”, Washington, 1962)

This definition puts in a nutshell what is most often inadequately done before undertaking exploitation of water resources. In short, it is the scientific inputs that are likely to be missed while planning water resources management projects. It is the “full life history of water” part of the above definition that is of specific relevance to the theme of this book, Isotope Hydrology.

Conventional hydrology is strong on measurement and quantification of different parts of the hydrological cycle (Fig.1.1), be it precipitation, run-off, evaporation, transpiration, infiltration, groundwater dynamics etc. Through chemistry and isotopes, we try to understand the processes themselves in order to delineate the history of that part of the hydrological cycle that is being studied. For example, if we are measuring river flow, we would like to know the contribution of different components; base flow, rainfall run-off and snow melt, if any.

Let’s see what we know and what do not know in the conventional hydrological practice. We know surface waters evaporate, form into clouds and precipitation occurs under favourable weather conditions. What we often do not know is the source of moisture, oceanic or inland.

Insect and non-insect pests cause extensive damage to standing crops, stored grains and stored products resulting in huge economic loss. Besides these, several pests cause annoyance, as well as attack livestock such as, cattle, poultry and pet animals. Some others damage household articles such as, clothing, upholstery, carpets, paper, books, leather articles, wooden and bamboo furniture and all sorts of wooden structures. These obnoxious creatures besides consuming any kind of food materials, spoil them by contaminating and polluting them with their faecal matter and urine and impart a repulsive, bad odor and make them unfit for consumption by humans and livestock. The damages caused by them pave the way for easy access and infection by some of the saprophytic microorganisms, which hasten the deterioration process. A few of these microorganisms produce mycotoxins, which are poisonous and may even be fatal to the consumers.

Among the household pests, cockroaches, crickets, silver fish, ants, white ants, carpet and powder post beetles and clothes moths are quite important. These insects not only cause annoyance but different types of flies, mosquitoes, bugs, fleas and lice either suck and feed on the blood from humans, cattle, poultry etc. but are also responsible for disseminating several disease causing microorganisms.

Mango (Mangifera indica)

1. Mango hoppers

(i) Amritodes atkinsoni (ii) Idioscopus niveosparsus and (iii) I. clypealis

Order - Hemiptera

Suborder - Homoptera

Family - Cicadellidae

Nature of damage. Three different species of hoppers are found to cause damage to mango trees. During some years, especially during the months of November-February, when the mango trees come to flowering, the pest appears in large numbers. During the other months, the pests are seen in much lesser numbers in an active form, while the other insects hibernate under the bark of the trees. Even in the peak period of pest occurrence, after a few heavy showers, the number of insects is considerably reduced.

During the cold season, when the trees put out the flower spikes, thousands of hoppers, young and adults appear in large numbers, pierce, suck and feed on the sap from the tender shoots, flower stalks, flowers and buds. This drain of the sap causes the buds and flowers to dry, wither and they are shed in large numbers, as a result fruit production may go down by 25-60 per cent. When a severely infested tree is approached, thousands of hoppers hop or fly about and make a rustling noise, as they dash against the foliage. The hoppers exude a sweet, sticky fluid excretion and this fluid thrown out by myriads of these insects after feeding on the tree sap, wets the soil underneath the trees and on the surface of the leaves of the trees. In case of severe infestation, the fluid may fall down in drops. The secretion attracts scores of flies, bees and other insects, which come to feed on the secretion. The infested tree presents a sickly appearance. The trees get devoid of buds and blossoms. The leaves appear shiny and are covered by ‘sooty mould’, a fungal disease. Thousands of caste skins of the nymphs are found on the shoots and leaves. The continuous damage caused to the trees year after year by the pest makes them loose their vigor gradually and eventually leads to severe reduction in their yielding capacity.

Life cycle of the pest. The female hopper inserts spherical, pale whitish eggs singly into the plant tissues through slits made in the young shoots, flower stalks and flower spikes. The eggs hatch in 4-6 days and the young nymph hatching out of the egg looks quite similar to the adult. The nymphs are very active and move about rapidly along the flower spikes and shoots, suck and feed on the plant sap. They are smaller in size, wingless and unable to fly or jump. The young ones moult their skin a few times during their growth and become adults in 10-15 days. The adult hoppers are small insects, about 3.0 mm. in length with a wedge-shaped body. The head is broader and the body gradually narrowing backwards. The legs are well developed, especially the hind legs. The general color is light greenish-brown. They are extremely active and can fly and hop around. They have a tubular, sucking mouthpart by which they puncture the tender plant parts and floral parts. The adults of Idioscopus clypealis are smaller, with two black spots on the prothorax and a few black spots on the front portion of the head, while those of Idioscopus niveoparsus are slightly bigger with three black spots on the prothorax and whitish, distinct cross bands on the light brownish forewings. The adults of Amritodes atkinsoni are bigger than the other two species, about 5.0 mm. in length, with two black spots on the prothorax. Two or more generations may appear during the flowering season of mango trees (Fig.71).

PESTS OF CEREALS

Rice (Oryza sativa)

Rice is the staple food of a vast majority of people throughout the world, especially in India. Rice crop is grown in about 75 million acres, which is about one-third of the total world area under rice. The warm and humid environment for the rice crop is best suited for invasion by several insect pests and as many as 85 species of insects are known to infest this crop. The damages caused by different pests extend from the seedling to harvest stages of the crop. Some of these pests are widely distributed and cause extensive damage. The more important pests are described below:

1. Rice stem borer or Rice yellow stem borer

Scirpophaga (Tryporyza) incertulas

Order - Lepidoptera

Family - Pyraustidae

Among the pests, which ravage rice crop, ‘rice stem borer’ is a major one and infests rice crop at all growth stages, from seedling to flowering. It is a specific pest of rice alone and is more serious during the months of October-January. The pest has a wide distribution in all Asian countries. The damages caused by this pest ranges from 5-20 per cent. Generally, late varieties of rice are more severely infested than the early maturing varieties, because of the possibility of the pest multiplying in larger numbers by the time the late varieties come to maturity. Cold weather with high humidity and low temperature prevalent during October-December is found to be conducive for the multiplication of the insect.

Introduction

Seed pathology has been recognized as its own specialization for a relatively brief time, and the term “Seed Pathology” was first coined by Mary Noble in the 1940 (Agarwal and Sinclair, 1997). Seed pathology is an essential part of seed technology as well as a sub discipline of plant pathology. According toAgarwal and Sinclair (1997), it may be defined as the study of seed borne disease and pathogens carried with seed. It also includes studies on the mechanisms of seed infection, seed transmission, the role of seed borne inoculum in disease development, methods for the detection of seed borne pathogens and non-pathogens, seed certification standards, mycotoxins and mycotoxicoses, and various methods for control of seed borne disease. Seed pathology includes the study of diseases and deterioration caused by bacteria, fungi, nematodes, viroids, viruses, physiological and mechanical disorders.

Neergaard Paul is considered the father of seed pathology. He was one of the founding father and later served as Director of the Danish Government Institute of Seed Pathology for Developing Countries, Copenhagen, Denmark, from 1956 to 1974. He served as the Chairman of the Plant Disease Committee of the International Seed testing Association (ISTA). During his tenure as Chair of ISTA, he helped standardize methods for the detection of seed borne fungi.Neergaard (1977) authored a two-volume text entitled “A Seed Pathology”. This text has served as a reference and teaching standard for the science of seed pathology throughout the world (Agarwal and Sinclair, 1997). This text focused on a wide variety of seed pathology issues, ranging from the economic significance of seed borne diseases to the assessment of seed borne inoculum.

Introduction

In India, around 70 per cent of cultivated land is under rainfed condition, but it accounts for about 42 per cent of the total quantity of produced food grains (Sujatha et al., 2013). It was estimated that using quality seeds, productivity can be enhanced up to the extent of 15-20 per cent and under optimum management, the increment may touch upon up to 45 per cent depending upon the crops. Quality seeds play a major role, along with improved package of practices leading to enhanced productivity. Crops propagated with seeds face many problems: Poor seed germination, poor seedling establishment under several abiotic stresses such as, drought, salinity and poor seedling vigour. The capacity of a crop propagated with seeds to grow depends on its genetic constituent and its interaction with the environmental biotic stresses. A number of diverse materials/ treatments at varying doses have been used to increase the rate and uniformity of seedling emergence in many field crops, which are generally categorized for seed enhancement. Seed enhancement may be defined as “post-harvest treatments that improve germination and seedling growth or facilitate the delivery of seeds and other inputs/materials required at the time of sowing smoothly”. Seed enhancement technology predominantly possess a central objective to further improve seed performance by treating with specific additives/chemical/organics/botanicals etc. under very specific regimes and with the aid of certain planting equipments to grow uniform crop obviously to harness higher productivity and production (Halmer, 2006). There are several ways and means to enhance vigour of germinating seedlings while emerging from the seed, which produce a uniform crop stand and finally substantially more yield is achieved by adopting simple techniques.

Introduction

Quality seed plays seminal role in augmenting agricultural production as well as productivity. Only by using good quality seeds, productivity can be enhanced up to the tune of 15-20 per cent alone, but under optimum management, the increment may touch upon up to 45 per cent depending upon the crops since the efficiency and efficacy of all other inputs in the production technology gamut are contingent upon the quality of seeds being used. Since antiquity the importance of quality seed to enhance agricultural productivity is well evident as mentioned in old testimonials, literatures, scriptures, treatises, epics, and many other ancient documents.

Seed quality is the major decisive factor governing stand establishment of any crop and thus having immense importance and bears utmost priority in case of high value, low volume crops like vegetables in particular and for high volume low value crops in general for enhanced productivity and production as well (Mandal et al., 2015). A number of diverse materials/ treatments at varying doses have been used to increase the rate and uniformity of seedling emergence in wheat and rice, which are generally categorized for seed enhancement, which is a kind of value addition.

Seed enhancement may be defined as post-harvest treatments that improve germination and seedling growth or facilitate the delivery of seeds and other inputs/materials required at the time of sowing smoothly. Seed enhancement technology predominantly possess a central objective to further improve seed performance by treating with specific additives/ chemical/ organics/ botanicals, etc. under very specific regimes and with the aid of certain planting equipments to grow uniform crop obviously to harness higher productivity and production (Halmer, 2006). Various techniques have been employed to assure superior performance of additives in different crops and most have been found to have immense commercial application (TeKrony, 2006). This includes three general areas of enhancement: pre sowing hydration treatment (priming), coating, pelleting technologies and seed conditioning.

Heterosis

The superiority of F₁ hybrid over both its parents in terms of yield or some other characters or heterosis is increased vigours, growth, yield or function of a hybrid over the parents, resulting from crossing of genetically diverse organisms. The term heterosis was first coined by Shull in 1914. Generally heterosis manifested as an increase in vigour, size, growth, yield or some other characteristics. But in some cases, hybrid may be inferior to the weaker parent this is also regarded as heterosis.

Introduction

Seeds are regarded as carriers of new technology and serve as basic catalytic input for enhancing the agricultural production. Hence the timely availability of quality seeds of the right variety in adequate quantity decides the strength of an agricultural economy. The intensive crop improvement programmes have resulted in the development of large number of hybrids and high yielding varieties in many important crops. Today, the Indian seed industry is the fifth largest seed market in the world, accounting for 4.4 per cent of global seed market. In terms of global trade, India is almost self-sufficient in flower, fruits and vegetables and field crops seeds (Anonymous, 2015). Economy of crops depends on good crop variety. Farmers choose these verities based on good quality traits and satisfactory yield. Thus, it is always essential to do fidelity check of all plant variety. The genetic purity is one of the most important aspects of quality control. Seed quality includes good germination, purity, seed health and vigour. With the increase in seed industry, there has been a refinement in the techniques used for testing genetic purity or genuineness of seed purity. Methods for testing genetic purity include different morphological, chemical, biochemical and molecular markers. Under PPV & FR Act, DUS (distinctiveness, uniformity, stability) testing procedure is performed with morphological descriptors. However, in agriculture, biotechnology has found applications in checking of true to type of clones and variety identification programs using molecular and chemical markers. Markers that reveal polymorphisms at the protein level are known as biochemical markers, while DNA markers reveal polymorphisms at the DNA level.

Introduction

Seed certification is a legally approved system for quality control of seed multiplication and production. Seed certification procedures are designed to ensure physical and genetic purity, freedom from other crop seeds, objectionable and other weed seeds and designated diseases with good germinability of the foundation and certified seed. Seed certification is done by the State Seed Certification Agency of the concerned state (SSCA) notified under section 8 of the Seeds Act, 1966 or by National Seed Corporation (NSC), where State Seed Certification Agency does not exist. The General Seed Certification Standards are applicable to all crops, which are eligible for certification, while field and seed standards are applicable to individual crop, constituted as the minimum seed certification standards. The word ‘seed’ or ‘seeds’ as used in these standards also includes all the propagating materials. Seeds or propagating material, which does not meet the standards of seed certification prescribed in the Indian Minimum Seeds Certification Standards, 2013 (Gunasekaran and Trivedi, 2013), are not certified by the Seed Certification Agency. The general seed and field standards for various crops are given at the end of this chapter.

Introduction

Seed vigour is an important quality parameter, which needs to be assessed to supplement germination and viability tests to gain insight into the performance of a seed lot in the field or in storage. Several definitions have been offered to explain seed vigour. Isley (1957) defined vigour as “the sum total of all seed attributes, which favour stand establishment under unfavourable field conditions”. While, AOSA (2005) defined seed vigour as the sum total of all those properties in seed, which upon planting, result in rapid and uniform production of healthy seedlings under a wide range of environments, including both favourable and stress conditions and ISTA (1985) stated that seed vigour is the sum total of those properties of the seed, which determine the potential level of performance and activity of a non-dormant seed or seed lot during germination and seedling emergence.

Methods of Analysis

Organic material especially, seeds, grains, fruits and nuts contain mainly three groups of compounds. They are carbohydrates, proteins and fats/oils, mostly in that order. They also contain 3-5% minerals and smaller quantities of vitamins and other minor constituents. Cereal grains contain more of carbohydrates while oilseeds contain more oil. Tree nuts and even oilseeds may contain 30-50% protein while cereal grains contain 5-8% protein. The starch and sugar contents of oilseeds may be less than 10% while the oil content of cereal grains ranges around 5%. The actual content and the composition of these groups of compounds really account for the quality as well as their commercial value.

The composition and quality of grains and other plant products vary with respect to their genetic background, location or the soils under which they are grown, season or the environment, the maturity of the grain/product or its harvest stage and the post harvest processes including storage etc. Crop scientists have in recent years been bringing out made to order or designer seeds, whose quality and composition need to be examined to satisfy the needs of the quality conrol and consumer requirements. Keeping this aspect in view this chapter has been designed.

As this book deals with oilseeds, emphasis has been placed on methods of evaluation relating to thier composition and quality. This chapter deals with methods of oil, protein and sugar analysis. Oil being the major constituent of oilseeds, importance has been given to methods of oil quality evaluation including fatty acid profile. Antinutrients especially aflatoxins, glucosinolates, ricin, oxalate, phytic acid, oligosaccharides, etc. also find a place. Analytical methods of some vitamins and minerals have also been included. Only a few important and most essential procedures relating to oilseed quality have been presented. The analyst can find more details and methods of evaluation of other constituents in standard laboratory analytical manuals.

Antinutrients

Safety is the most important aspect among all the quality attributes of food. Food can be considered safe, only if it does not contain any factor which is hazardous to human or even animal health. The various factors which affect the safety of the foods may be broadly classified into three categories. The first category includes the toxic factors occurring naturally in foods. The second category comprises a group of incidental contaminants which find their way at various stages of processing, manufacture, preservation and storage of foods and the third category includes harmful intentional additives or adulterants.

Various categories of anti-nutritional factors are present in the traditional and non-traditional oilseeds, oils and oilcakes. Some of them are heat-labile and do not pose any harmful effects in the body, while the heat-stable factors may cause deleterious effects in human beings and animals. They belong to different groups of compounds. It is necessary to know their behaviour, significance and toxicities. Their avoidance or elimination is important to protect human and animal health.

Nutritional Quality of Edible Oils

Fats improve the taste and flavour of foods. Fatty foods satiate a hungry person fast because fats remain in the stomach for a longer period than either protein or carbohydrate (sugar) foods. Fats also carry essential vitamins like A, D, E and K. They also provide the body with essential fatty acids. Thus, fats have a very important role to play in human nutrition.

Spectrum of Fats and Oils

It is not just the butter and ghee that provide us the necessary fats. Vegetable oils, meat and fish too add fats in our diet. There is an array of vegetable oils available to human beings. They are groundnut, rapeseed, sesame, sunflower, safflower, soybean, niger, cotton seed, coconut, palm and rice bran oils. Ghee(butter fat), however, is the main animal fat utilized widely. The quality and composition of these oils vary as also the preference of people.

Introduction

Germination is the growth of a plant contained within a seed; it results in the formation of the seedling, it is also the process of reactivation of metabolic machinery of the seed resulting in the emergence of radicle and plumule. The most common example of germination is the sprouting of a seedling from a seed of an angiosperm or gymnosperm. The seed of a vascular plant is a small package produced in a fruit after the union of male and female reproductive cells. All fully developed seeds contain an embryo and, in most plant species some store of food reserves, wrapped in a seed coat. Most seeds go through a period of dormancy, where there is no active growth; during this time the seed can be safely transported to a new location and/or survive adverse climatic conditions until circumstances are favourable for growth. Dormant seeds are ripe seeds that do not germinate because they are subject to external environmental conditions that prevent the initiation of metabolic processes and cell growth. Under proper conditions, the seed begins to germinate and the embryonic tissues resume growth, developing towards a seedling. In short, seed germination is the ability of a seed to develop in to a normal plant under favourable conditions in the soil (ISTA, 1985) or the process by which the dormant embryo wakes up and begins to grow is known as seed germination.

Post Harvest Technology

Introduction

The demand for edible oil has grown with the increase in world population. Improvement in living standards have made the population increase the consumption of oils and fats. It also has become more discriminating with respect to the oil quality. Oil producers, have to meet the increasing demand for edible oil, and improve product quality and variety as these have become major factors in the market-place.

Agriculture has been tuned through selective seed breeding and improved crop production practices to take care of the increasing demand. The emphasis has been to improve yield per hectare or tolerance to climatic variations. The ability to modify seed through traditional breeding and biotechnological approaches promises a revolution in agriculture. Using various approaches, not only quantitative improvement but also the qualitative changes especially fatty acid changes have been brought about. Customer support is needed for the genetically modified crops. A lot of controversy exists at present in accepting genetically modified crops. This aspect has to be studied in depth and needs to be resolved at the appropriate level as quickly as possible.

A prerequisite for the production of top quality oils and meals is a high quality raw material. Some attempts have been made to improve the physical characteristics of oils and meals through genetic, agronomic as well as through post production handling and processing technologies. The harvested quality grain should not be damaged during transportation, storage and processing. To produce a crude oil, the industry uses a number of processing steps, the application of which depends on the type of seed and the scale of the operation.

The purpose of Post Harvest Technology of oilseeds is to recover the maximum quantity of good quality oil and also make the deoiled cake useful as food or feed. Oil in oilseeds is located in spherosomes, which are the oil bodies (Salunkhe et al, 1992). When seeds are broken into small particles and the cells get ruptured the oil becomes available and is easily extracted. From the time of harvest, till the seeds are fed to the oil extracting machines, various processes are carried out to make good quality of oil available to the consumer apart from providing remunerative prices to the producer, namely, the farmer. The various steps involved in the oil extraction are proper harvest, drying, storage, seed cleaning, heat treatment and different types of machinery. The basic objective of every step in the post harvest technology is to minimize losses and to sustain or improve the quality of the product.

In addition to cultivated oilseeds, many other seeds and related plant products serve as sources of vegetable oils. They are obtained from large trees, shrubs or from different crops and their products. It may be the seeds or the husk, or the germ or other parts of the fruit or seed which are rich in oil. These are in general, referred to as non-conventional vegetable oil sources. They are highly important for the food/feed and non-food industries. Non- food and industrial uses are plenty.

But for the availability of these non- traditional oilseeds and their products, there would have been great pressure on the cultivated seeds. The products, mainly oil, help run our machines and protect them from getting rusted. Some of them protect our crops from pests and deseases. They even serve as beauty aids in the form of cosmetics. Some of them serve as sources of medicine for men and animals.

In recent years, some non-conventional/ non-edible oilseeds have become the raw material for biofuel/bioenergy. They have gained prominence, due to shortage of conventional oils. Seeds of more than 100 species occurring in the wild or cultivated are known to contain oil in considerable quantities. There is a vast scope for production and utilization of oil from these sources (Ambasta, 1986, Bhattacharya, 2002 and Vimal and Naphade, 1980).

In this chapter, the major non-conventional oilseeds of tree origin, by product oilseeds or other minor sources, are being dealt with. They are ricebran, corn, sal, mahua, jatropha, kokum, melia, rubber, mango kernel, kusum, simarouba, neem, karanj, crambe, moringa, tumba, jojoba and tobacco seed etc. Emphasis is given to the composition and quality of oil, cake and other plant parts. Their food, non-food and medicinal uses are presented. Oil extraction and related post harvest technological aspects are also discussed.

Introduction

The seed industry has witnessed a substantial change in the 20th century, with farmers relying on purchasing seeds from market with better traits rather than relying on seeds from previous season’s harvest. Developments in seed technology have increased the momentum of the industry’s growth, and the introduction of genetically modified crops has further boosted the seed market. The value of global seed market has tripled since 2000 and reached US$ 54 billion in 2014 (Indian Seed Market (pdf), www.icfa.org.in).

Groundnut

Groundnut roundnut is believed to have originated in Brazil and later spread to many countries all over the world. It is known to humanity since 950BC. Groundnut crop and its products have multiple uses. Being a leguminous crop it enriches the soil with nitrogen through symbiotic biological fixation by rizhobium. The economic product, groundnut in shell, contains the seeds, which are edible. The shell as well as the haulms serve as fuel and fodder. The seed oil serves as a good cooking oil while the cakes are good sources of protein for animals and even humans. Groundnut (Arachis hypogaea L,) belongs to leguminosae family and papilionacea sub family. It consists of two sub species each with two varieties. The first one hypogaea has the variety hypogaea (virginia group) and variety hirsuta kohla while the second one fastigiata has the variety fastigiata (valencia group ) and the variety vulgaris (spanish group). Hypogaea varieties are spreading types with branching and lack infloresence on the main stem. They are of longer duration and have fresh seed dormancy . Varieties of the fastigiata are of erect type with branching and flowering on the main stem also. The crop is of shorter duration than hypogaea types, but with little fresh seed dermancy.

The major groundnut producing countries of the world are China, India, Nigeria, U.S.A. Indonesia, Argentina, Sudan, Senegal and Myanmar. The cultivation is spread in tropical and sub-ropical regions. Groundnut is a self- pollinated crop and pollination takes place in the morning. After fertilization an elongated stalk namely peg develops which enters the soil, bends horizontally and swells to become a pod. Within the pod, two, three or four kernels are formed. The crop can be grown under rainfall conditions ranging from 50-125cm, with good distribution during flowering and pegging stages. Sandy loams, loamy soils, and black soils with good drainage are suitable for growing the crop.

Human being as a hunter has depended mostly on animal food and some fruits. With the progress of civilization, he settled down and

started agriculture around 7000-10,000 B.C. He started depending on plant grains to take care of his energy and nutritional requirements in addition to animal foods. Initially cereal grains must have mostly accounted for his staple food requirements. Taste and health requirements must have prompted him to diversify his crop production programme. It is this need that must have made him to cultivate oilseeds, fibre and other crops.

Oilseeds, thus, have been under cultivation since antiquity. Rapeseed and sesame have been described in the Indian Sanskrit writings of 2000 BC. Historically, extraction of oil seems to have been a batch process. Seeds kept in gunny bags or boxes were pressed to remove oil. The separated oil on clarification was used for food and non food purposes. The resulting cakes were utilized as animal feed or thrown away into fields which helped in improving the soil fertility. Human beings slowly discovered the uses of oil and other oilseed products for various food and non-food purposes.

There are several species of plants in the world whose oil can be utilized for human consumption. Though around 40 oilseeds are known, only around a dozen oilseed crops have become commercially important. There are ten seed crops and three tree crops. The seed crops are groundnut, rapeseed- mustard, sesame, soybean, sunflower, cottonseed, safflower, niger, castor and linseed. These are mostly annual crops. The three major tree oil crops are palm, olive and coconut.