eChapters

1. GENERAL INFORMATION!

Major constraint of medicinal plants: Lack of genuine planting material.

Maximum number of medicinal plants belong to family Asteraceae.

Maximum demand in world market: 1. Senna leaves 2. Isabgol seeds 3. Cassia tora seeds.

India is largest producer of 1. Kewada oil 2. Senna 3. Davana oil 4. Isabgol.

India is 2^nd largest producer of 1. Opium latex 2. Jasmine concrete 3. Tuberose concrete

India is 3^rd largest exporter of periwinkle.

Thailand is largest exporter of sarpagandha leaves.

China is largest producer of 1. Geranium oil 2. Citronella oil.

Abstract

Rheological properties of dough from different flours are very important to know about the kneading and modeling process especially for development of bakery products. Rheological testing is helpful to examine the structural and fundamental properties of dough. The basic principle underlying evaluation of rheological properties are mechanical behavior of the dough, in conjunction with the physical structure of the dough, the molecular structure of the protein continuous phase in the dough and with chemical reactions of functional groups. This chapter presents some of the methods currently used in bakery industry for determining the rheological characteristics of the flour and the dough. The instruments such as Farinograph, Mixograph, Extensigraph, Alveograph and Amylograph, which are used for the measurement of dough rheological properties (due to visco-elastic behavior of dough) were described.

Abstract

Quality assessment of fruits and vegetable before marketing and processing is an essential task. Various destructive and non-destructive methods have been investigated to achieve this goal. Among the several prevalent noninvasive methods, optical properties measurement methods also promotes for nondestructive quality inspection of fruits and vegetables. The optical properties of biological tissue are, therefore, very importance important for getting sample information and data quantification of the inside of the material. The main goal of this chapter is, thus, to introduce fundamental concept of optical properties, its principle and application in fruits and vegetables. The discussion of electromagnetic radiation for better understanding of the nature of light has also been explored.

Abstract

Food texture is one of the most widely measured quality attributes during postharvest handling, processing, and consumption. Given the subjectivity in human perception of food texture, texture measurement remains a complex exercise and thus presents both a charm and challenge for researchers and industry practitioners. For fresh foods such as fruit and vegetable, textural properties such as firmness are widely used as indices of readiness to harvest (maturity) to meet requirements for long term handling, storage and acceptability by the consumer. For processed foods, understanding texture properties is important for the control of processing operations suchasheating, frying and drying to attain desired quality attributes of the end product. Texture and viscosity measurement is one of the most common techniques and procedures in food and postharvest research and industrial practice. Foods are complex systems exhibiting various degrees of elasticity, viscosity, and plasticity. Because of its complex structure and mechanical behavior, objective measurements of food texture may be influenced by a variety of test conditions, including rate of loading, the magnitude of deformations imposed upon the material, geometry of the loading surface, and localized yielding within the product tested. Various approaches have been used to evaluate the sensory attributes of texture in foods. However, the high cost and time consumption of organizing panelists and preparing food limit their use, and often, sensory texture evaluation is applied in combination with instrumental measurement.

Abstract

Herbal Burfi was development with various types of milk viz., Buffalo (6% Fat), Cow (4% Fat) and mixed milk (5% Fat) and different levels of sugar i.e. 20, 25, 30 and 35 per cent (weight basis of khoa). Each sample was fortified with 5g satavar and safed musli powder. Other minor ingredients like Almonds, Cardamoms, Cashew nuts, Pistachio nuts, etc were mixed thoroughly and after preparation herbal burfi was allowed to set at room temperature (20- 25_oC) for two hours. Physico-chemical (acidity, pH, fat, protein, lactose, sugar, ash and total solids), microbial (total plate count, coliform count, yeast and mould count) quality and sensory attributes of the herbal burfi were evaluated. The data of experiments were statistically analyzed to compare significance effects of various factors by applying factorial Randomized Block Design (fRBD) with the help of OPSTAT software and ANOVA.

Cashewnut is an important delicious and dollar earning cash crop of India. This crop was remained neglected due to its poor yield potential and prolonged harvesting season. Cashew was introduced mostly for soil conservation purposes. In the beginning of the 20^th century cashew kernels gained importance in the international trade as edible nut and the crop began to be considered as having commercial value. Cashew is commercially grown for its kernels although cashewnut shell liquid (CNSL) and apples are also valuable by - products. It is considered to be the most important edible nut in the world trade (Ascenso, 1986). India is the largest producer and exporter of cashewnut in the world. Cashew kernel is the rich source of protein, carbohydrate, unsaturated fats and minerals like calcium, phosphorus and iron. Cashew proteins are complete with all essential amino acids. Fats of cashewnut are considered as complete, attractive, easily digestible and non fattening, it can be used by both olds and infants. The cashew apple juice is rich in vitamin C and it has some medicinal properties.

SUMMARY

The vast amounts of biological data generated from various studies have become the cornerstone of bioinformatics. The very first challenge of this enormous data is to store and handle this large volume of information through the establishment and use of computer databases. These data describe a unique array of information on biological entities such as DNA, protein and other molecules. However, still a large amount of data remains hidden which needs to be explored by accessing these data from databases.

Biological databases play a vital role in the biological research from the fundamental molecular biology to the applied areas of biology viz. medicine, agriculture, biochemical industries etc. This chapter introduces some basic concepts related to databases such as features, construction and classification of biological databases, submission and retrieving of data from biological databases.

INTRODUCTION

Agricultural systems and the environment in which it operates have become increasingly complex which encompass both agricultural production and marketing systems. Both of them are rich in complexity and diversity (Spedding, 1975) and to understand the complexity and structure of such systems and their functions require the use of mathematical modelling frameworks that represent their key features. Disciplines that are required to develop and solve such models include: biology, computer programming, statistics, mathematics, economics, and social science. Models are being developed to investigate specific issues such as weed infestation, soil health, nitrogen cycling, the effects of climate change, climate variability, and to assist developing countries to improve their production at their farm gate. During the first half of 20th Century, most agricultural products were produced by means of labour and the majority of the produce was used for own consumption. However, as time progressed labour was substituted for machines, production became more market-oriented and consequently the practice of farming also transformed from “a way of living” to business enterprises run on business principles.

1. INTRODUCTION

Until the 1990s, the phrase Corporate Governance (CG) was relatively unknown but since then it has gained a huge importance when the corporate sector was surrounded with problems of unethical practicesand flagrant violations of rules and regulations in a number of countries. CG has received increased attention as multiple cases of risk of corporate failures both for public and private sectors. Multiple corporate failures worldwide, such as those of Maxwell, Enron, Global crossing, and Sunbeam forced the regulatory authorities to set up codes and standards on CG.The Indian market has also faced a number of scams since early nineties.Harshad Mehta Stock Scam in 1992 is one of the corporate frauds in the country which finally resulted in setting up of Kumar Mangalam Birla Committee in 1999. Based on their recommendations in 2000, Clause 49 on CG was inserted in the listing agreement of every stock exchange in India. The purpose was to promote and raise standards of CG of listed companies. CG has now become most common phrase in the business world of 21^st century. It is important for financial health of the corporations and relationshipwith the public at large; may it be an individual or community especially after the collapse of Satyam Software Services Ltd. in 2008.It has been made mandatory for the Indian companies to comply with CG norms, to give reports and disclosures as per the listing agreement and various provisions of the Companies Act in their annual reports. The importance ofCG in the 21^st century keeps on increasing as the economy is growing.

ABSTRACT

This paper broadly deals with salient applications of Information Technology in various areas related to Agriculture Research, Government’s digital initiatives, Indian Council of Agriculture Research IT initiatives in agriculture research as step, towards reaching agriculture knowledge and technology to small holders (Resource-Poor-Farmers). The present paper identifies new emerging areas of usage of computer application in Horticulture research and development.

INTRODUCTION

The horticultural sector is facing the challenges of dwindling land resources, increasing biotic and abiotic stresses, indications of factor productivity decline, threatened loss of bio-diversity, new IPR regime etc, (Adiguru and Mruthyunaja, 2004). Further, Indian agriculture has come under significant adjustment pressure from market liberalization and globalization. Farmers need reliable and timely information about best practices of production, processing, marketing, input and output prices, financial markets and risk-covering institutions. Existing public extension system has become outdated and ineffective in spite of the fact that it has been a catalyst in successfully heralding the Green Revolution in the country. This is partly due to an inadequate use of new means of information dissemination (Adhiguru et al., 2003). The public extension system follows a top-down approach and has become less interactive, more time-consuming and costly and fails to meet the expectations of those involved in the agricultural production and other involved in the value chain. Therefore, a new extension system re-oriented to meet the information needs of the farmers should be put in place across the country by using ICT.

1. INTRODUCTION

Science and Technology are vital for developing low-input and high-output agriculture and pharmaceutical. India needs frugal use of natural resources and diversification of agricultural activities. Transgenic technologies are highly misunderstood. Genetically modified crops are a result of them. In fact genetic modification of crops for human use is going on since their domestication. By introduction of Bt cotton in 2002, yields have doubled. American bollworm can no longer threaten Indian cotton crops. Insects can develop resistance to Bt gene or some virus attacking the crop needs more research. RNA-mediated gene suppression may aid the development of patent strategies that will support the next generation of genetically modified crops and enhance scope of patenting. Many fancy Organic farming, which will need 40 percent more agricultural land for present number of people on earth although it is ever increasing. Biotechnology has revolutionized agriculture, healthcare, industrial processing, environmental sustainability and is also a revenue generator. India is poised for a tremendous growth in BT sector. NanoBT has now entered into furthering the useful research on faster pace. It has scientific and technical pool of human resources, rich biodiversity, large agricultural and market base for new BT products and world recognition as a producer of low cost, high quality bulk drugs and formulations. Issues surrounding Intellectual Property Rights and BT inventions are varied but interrelated. Basic research has to be transferred to applied field and the resultant is to be commercialized. In some countries, plant varieties are protected by sui generis system. Post genome research has added fuel to the fire; new innovative fields, like ‘Bioinformatics’ with plenty of biology information and new processing methods have emerged. BT uses four tools of IPR, viz. Patents, Trademarks, Trade secrets and Copyright. At present, its contribution to the World’s patenting activity is less than three percent. As such there is a necessity to amend the IP laws to give better protection to R&D, and better enforcement of IP, technology transfer and licensing arrangements. Biotech industry in India is flourishing more in pharmaceuticals, particularly in healthcare. There is an urgent need for harmonization of administration and centralization of the patenting process in accordance with WIPO diktats.

Abstract

Mentheae, one of the largest tribes of subfamily Nepetoideae of family Lamiaceae is represented by five genera (Mentha, Nepeta, Origanum, Salvia and Thymus) in Jammu and Udhampur districts (Jammu division). Frequent surveys made of these districts to generate ethnobotanical data revealed the existence of Mentha arvensis L., M. longifolia (L.) L., M. piperita L., M. spicata L., Nepeta cataria L., Origanum vulgare L., Salvia splendens Sellow ex Schult and Thymus serpyllum L. While the enlisted Mentha species are represented more or less equally in the two districts, N. cataria, O. vulgare, S. splendens and T. serpyllum are mainly adapted to temperate regions of Udhampur. The frequent interactions with the locals indicated that except M. spicata whose leaves are used for seasoning dishes or preparing refreshing drinks and those of O. vulgare which find utility in making herbal tea, others are largely used for therapeutic purposes. Amongst these species, maximum use value was noted for M. longifolia (0.81) followed by that for M. arvensis (0.69). So far as agreement among the informants regarding the usage of a species for curing a particular disease is concerned, it came out to be maximum for both M. longifolia and M. arvensis for treatment of respiratory (Fic=0.93) and gastrointestinal problems (Fic=0.93). In our study, most of the informants have predisposition towards using M. longifolia for treating respiratory disorders particularly cough and cold. For this species, fidelity level was found to be maximum equal to 33.33%. This indicates that M. longifolia carries great potential for using in new herbal formulations. Finding of lesser use value for O. vulgare (0.21) and T. serpyllum (0.30), reportedly having many medicinal important components, is a matter of concern. The probable reasons underlying quite less usage of these taxa have also been discussed in this communication along with the future prospects of cultivating these.

Abstract

Genus Chlorophytum is represented by approximately 300 species of rhizomatous plants, distributed predominantly in tropical and sub tropical forests of the world. Most of these are medicinally important. Chlorophytum borivilianum Santapau & R.R. Fern among these is highly valued because of high saponin content mainly concentrated in its tuberous roots. These steroidal saponins are important bioactive components responsible for aphrodisiac attributes of this species in addition to several other benefits. Present communication reviews the data available on medicinal properties and phytochemical constitution of the species.

Abstract

India with plethora of flora and fauna is a rich repository of cultural and ethnic diversity. Bestowed with varied biogeographically distributed ecosystems and biodiversity hotspots, the country has always been the torch bearer as far as ethnobotanical knowledge is concerned. Jammu and Kashmir in the North-Western part of India has a rich biological and cultural diversity. Owing to the distinct geographical location and varied climatic conditions, district Poonch represents a rich repository of biodiversity including the wealth of medicinal plants. This study aimed at documenting and examining the use of plants in various medicinal herbal preparations. A total of 223 plant species belonging to 77 families and 173 genera were documented to be used as ethnomedicine by people residing in the study area. The portion of plant parts used were leaves (28.14%), followed by root (16.33%), fruit (11.55%), whole plant (10.3%), stem (09.79%), flower (7.53%), seed (5.27% each), rhizome (4.77%), tuber (3.76%), bulb (1%) and bark and latex (0.75% each). These parts are utilized as herbal remedies for curing 109 human ailments such as abscess, acidity, asthma, back pain, body pain, boils, cancer, cholera, cold, cough, dandruff, erectile dysfunction, eye pain, fever, gastroenteritis, haemorrhoid, high blood pressure, menstrual disorders, sexual disorders, stomach pain, diabetes, diarrhoea, dysentery and weakness. The dominant disease was fever (52), followed by abdominal pain (30), cough (29), headache (22), constipation (20), diabetes (18), wounds (17), weakness (16) and others. There is need for proper documentation and an attempt has been made to highlight high value medicinal plants so that proper strategies could be made for their conservation.

Abstract

Pomegranate, Punica granatum L., is an ancient fruit tree native to the Middle East. All plant parts are rich source of the various secondary metabolites that accounts for its antioxidant and health-promoting activity. A strong genetic control on anthocyanin production is responsible for variability in the color of peel and arils of pomegranate. Characterization, cloning and expression of the genes related with anthocyanin and tannin production provides routes for engineering of these complex pathways. Recent studies on pomegranate genome sequencing have elucidated several biochemical pathways and candidate genes that could assist to increase production of potent bioactive compounds in near future. This will further facilitate our understanding to some exclusive biological processes that plays a significant role in pomegranate breeding.

Indian hot arid zone which is about 12% of total geographical area of the landmass of 0.32 million km² has maximum covering in western Rajasthan i.e. 61% of the total area whereas the other areas in arid region are available in the states of Gujarat, Punjab, Haryana, Andhra Pradesh and Karnataka accounting for 20, 5, 4, 7 and 3% of hot arid area whereas the cold arid area of 8.4 million ha lies in the state of Jammu & Kashmir covering the Leh and Ladakh region.

The hot arid area is characterized by frequent droughts of 47% of frequency in the last century of moderate to severe nature. Due to higher occurrence frequency of droughts in this region of state, the livestock assumes great importance as a drought management measure as agriculture is at the mercy of rainfall pattern which is very uncertain in amount as well as distribution coupled with poor soil condition, higher evapotranspiration and higher wind velocity causing the soil erosion.

For arid region of Rajasthanthe general climatic conditions, topographical features and biotic factors do not encourage agricultural operations in the absence of extractive industry the peasantry has to fall upon animal husbandry as their main occupation. Rearing some of the finest breed of cattle, camel, sheep and goats known for their endurance making much use of the meagre feed resources which are grasses ,herbs, shrubs, tree leaves and cultivated feed and fodder crops. Livestock farming has some in built superiority over crop farming as far as growth; stability and resource conservation are concerned. On an average, the region experiences 3 years of drought in every 10 years. The natural forces constituting the soil-climatic complex, which conspire to reduce the crop productivity and cause instability in agricultural production, have much less impact on livestock farming. This is due to differences in the nutritive value of natural vegetation, which mainly sustains livestock.

Sustainable development and efficient management of water is an increasingly complex challenge in India. Increasing population, growing urbanization and rapid industrialization combined with the need for raising agricultural production generates competing claims for water. Ground water has an important role in meeting the water requirements of agriculture, industrial and domestic sectors in India. About 85 percent of India’s rural domestic water requirements, 50 percent of its urban water requirements and more than 50 percent of its irrigation requirements are being met from ground water resources. Ground water is annually replenishable resource but its availability is non-uniform in space and time. Technically, the dynamic ground water refers to the quantity of ground water available in the zone of water level fluctuation, which is replenished annually. Hence, the sustainable development of ground water resources warrants precise quantitative assessment based on reasonably valid scientific principles. National Water Policy, 2012 has laid emphasis on periodic assessment of ground water resources on scientific basis. The trends in water availability due to various factors including climate change must also be assessed and accounted for during water resources planning. To meet the increasing demands of water, it advocates direct use of rainfall, desalination and avoidance of inadvertent evapo-transpiration for augmenting utilizable water resources. The National Water Policy, 2012 also states that safe water for drinking and sanitation should be considered as pre-emptive needs followed by high priority allocation for other domestic needs (including needs of animals), achieving food security, supporting sustenance agriculture and minimum eco-system needs. Available water, after meeting the above needs should be allocated in a manner to promote its conservation and efficient use.

Introduction

Climate change has been, and continues to be one of the important causes of low productivity from animal agriculture in tropical countries like India through crop failures, fodder scarcity and increased incidence of endemic animal diseases. It impacts animal agriculture and cause immediate danger for human societies as livelihoods and food production are being adversely affected. Farm ruminant animals contribute to food supply by converting low-value materials, inedible or unpalatable for human, into milk, meat, and eggs and directly contribute to nutritional security. Besides contributing over one-fourth to the agricultural GDP, it provides employment to 18 million people in principal or subsidiary status in India. Nearly two-thirds of farm households are associated with farm animal rearing and 80% of them are small landholders (≤2 ha). As a result of various socio-economic and market driven factors, during the last one decade, large scale transformation took place in both extensive and intensive animal agriculture with regards to type and breed of the animal. A lot of high yielding, low disease resistant and more vulnerable crossbreed animal population have been increased in present animal production systems inorder to meet the market demands. Climate changes could impact severely the economic viability and production of these intensive animal production systems through increased incidence of drought/?oods/cyclones/hailstorms etc. Drought and high ambient temperatures in particular, affects production of milk, meat and egg, reproduction, health of animals and condition of pastures. Changes in pasture and crop biomass availability and quality affect animal production through changes in daily or seasonal feed supplies. Heavy rains and associated ?oods would washout the fodder resources and animals. Recent incidences of severe hail storms are causing brutal injuries to the grazing animals. To mitigate the adverse affects of extreme weather events and cope with changing climate, much precised resilient technologies suitable to local conditions and resources are needed. Hence, one should be critical in recommending smart animal-agriculture technologies in view of much diversified and heterogeneous group of farmers and the resources accessible to them. This will help in sustainable productivity from animal-agriculture and profitability to the farmers even in the era of climate change.

Introduction

R is a language and environment for statistical computing and graphics. It is a GNU project which is similar to the S language and environment which was developed at Bell Laboratories (formerly AT&T, now Lucent Technologies) by John Chambers and colleagues. R can be considered as a different implementation of S. There are some important differences, but much code written for S runs unaltered under R.

R provides a wide variety of statistical (linear and nonlinear modelling, classical statistical tests, time-series analysis, classification, clustering) and graphical techniques, and is highly extensible. The S language is often the vehicle of choice for research in statistical methodology, and R provides an Open Source route to participation in that activity. In a nutshell, R is an open-source software environment for statistical computing that is rapidly becoming the tool of choice for data analysis in the life sciences and elsewhere. It’s developed by a large international community of scientists and programmers and is at the forefront of new developments in statistical computing.

2.1. What is Greenhouse Technology?

Greenhouse technology involves primarily the structural design that can take care of climate control mechanisms to create proper micro-crop-climate and secondarily it involves the technology needed for optimum growth and production of crop grown under this structure. Combination of these two aspects may be expressed as ‘greenhouse technology’.

So the ‘greenhouse technology’ may be defined as “The technology required to built a structure, covered fully, partly or porously for manipulating the inside climatic conditions, under which crops/plants can be grown with special measures”.

5.1. Introduction

Back drop: Since the concept of greenhouse technology was introduced, metal and wooden structures were tried in different parts of the world. When greenhouse was brought in the tropical and sub-tropical areas, people tried bamboo as construction material for greenhouse instead of iron or wood. However, due to the non-standard character of bamboo, the standardization of design of bamboo greenhouse, as a model, was not possible. Actually all such designs were very much clumsy and not at all comparable to the well established models of greenhouse having metal or wood frame.

Hence it is an urgent call to establish a standard design of bamboo greenhouse that can efficiently compete with the other common & commercial greenhouses made-up of GI-pipes.

Innovation: This greenhouse is structured by matured, cured & treated bamboo instead of usual structural elements (GI/MS/wood). For that matter (1) innovated design and construction methods and (2) a new curing method has been generated. It is very tough to standardize the design of bamboo greenhouses, specifically due to the non-standardized nature of bamboo. Unlike GI/MS pipe etc, bamboos do not have the same dimensions and uniformity in size & shape (diameter/ width/thickness etc). Thus, in general, bamboo greenhouses are low in height and are of naturally ventilated type. However, there is still huge scope to work on design of bamboo greenhouse for different climatic situation to avail the benefits of its natural advantages and low cost.

Abstract

Indian agriculture is undergoing rapid transformation and agricultural-based food industry in India requires timely and adequate supply of good quality raw material for processing, value addition and export. The recent growth and diversification of consumer demand and the expansion of organized agricultural processing and marketing ventures in India has the potential to boost the market opportunities, productivity, and incomes of farmers, including that of marginal and small holders. However, achieving these goals will likely require creation of new institutions and innovations to develop supply chains and facilitate linkages between farmers, wholesalers, processors, and retailers. Among these institutions and innovations are various models of contract farming, including those led by cooperatives, by farmer groups, and by various types of private sector resource intermediation that develop backward linkages to growers. Contract farming is a system where agricultural production is carried out according to an agreement between a buyer and farmers, which establishes conditions for the production and marketing of a farm product or products. In other words Contract Farming is a system of production and supply of agricultural/horticultural produce under forward contracts between producers/ suppliers and buyers. The essence of such an arrangement is the commitment of the producer to provide an agricultural commodity of a certain type, at a time and a price, and in a quantity required by a known and committed buyer. Well-managed contract farming is an effective approach to help solve many of the market linkage and access problems of small and marginal farmers which constitute 86% of the farming households in India. This chapter examines growth and status including the performance of different models of contract farming based on empirical studies. It concludes that by entering into the contractual arrangement, the income level of the farmer and employment level in the rural economy has increased despite certain problems faced by the farmers like delayed payment, delay in procurement and low supply of agricultural inputs to them.

Abstract

Remote sensing has wider applications in agriculture right from landscape mapping, soil moisture, planting dates, cropping systems to climate change effects. Growing uncertainties of weather and climate change pose a major threat to food security of the country and thus warrant for farmers empowerment of informed decision in agricultural risk management. The technology is competent to monitor crop growth, predict crop yield in terms of quantity and quality, assists in estimating crop acreage, its condition, disease and pest status. Over the last two decades, the development of space technology has led to a substantial increase in satellite earth observation systems. Simultaneously, the Information and Communication Technology (ICT) revolution has rendered increasingly effective the processing of data for specific uses and their instantaneous distribution on the World Wide Web (WWW). Satellite data provide better coverage in time and in area extent than any other alternative. It is important to make maximum use of this information to monitor our environment. Access to these Satellite data and products is only the beginning. In addition, the ability to interpret, combine, and make maximum use of this information is an integral part of weather and climate management at the national level. Production estimates, post harvest and quantity available for market enable the farmers and policy makers to chalk out sustainable strategy to match supply with market demand.

12.1 INTRODUCTION

Water is a factor of prime importance in agriculture industry. Water management is one of the largest and most important inputs into an orchard. An efficient water management refers to artificial application of water, i.e., irrigation in crop root zones in case of soil moisture deficit and removal of water, i.e., drainage from the root zone in case of excess so as to provide the crops a most optimum soil moisture regime for best production. It means how best we are in irrigating and dewatering our fields so that plants are protected from stress as well as water logging (Goswami, 2015). Water resources are continuously overburdened with excessive drafts and water sources are shrinking at faster rate. Groundwater levels are falling at the rates faster than ever. Under this type of circumstances, judicious use of water should be given due attention for water conservation and also in increasing water productivity. Area under horticultural plantations is increasing at exponential rate. The unproductive uplands and low productive midlands and lowlands are brought under fruit based horticultural plantations. For a profitable orchard enterprise, a well-planned irrigation system and efficient water management practice are of utmost importance. Horticultural sector, which includes vegetables, f lowers and fruits, has enormous potential for development owing to varying agro-climatic conditions in India. There is tremendous scope for increase in productivity and quality of horticultural crops, which is necessary to compete in this modern competitive world market. There are many production technologies available to increase the per unit vegetable production and also to increase its quality. One of the widely acceptable, reliable and cost- effective technologies is pressurized irrigation.

Abstract

Remotely sensed data have become the primary realistic source for natural resources and biomass estimation, since last 30 decades. A summary of earlier research on remote sensing and GIS based biomass estimation approaches and a discussion of existing issues prompting biomass estimation are very valuable for further improving biomass estimation performance with the integration of geographical information systems. This paper discusses the recently most accurately alternative research methods to integration of remote sensing and GIS applications for identification, characterization and analysis of biophysical characters. The remote sensed data and geographical information systems using the accurate assessment of natural resource and management for the enhancement of biomass production and estimation. There is not any other option for the perfectly biophysical and natural resources estimation in small to large area. The earlier research has demonstrated that biomass estimation remains a challenging task, especially in those study areas with complex forest and mixed traditional cropping systems and environmental conditions. Either optical sensor data or radar data are more suitable for forest sites with relatively simple forest stand structure than the sites with complex biophysical environments. A combination of spectral responses and image textures improves biomass estimation performance. More research expertise is needed to focus on the integration of remote sensing, GIS& GPS, the use of multisource data, and the selection of suitable variables and algorithms for biomass estimation at different scales. Understanding and identifying major uncertainties caused by different stages of the biomass estimation technique and applying strength of mind to reduce these uncertainties are critical.

Keywords : Integrating, Remote Sensing, Bio-physical, Resources, Environment

Abstract

Geographical Information Systems (GIS) application in plant genetic resource management allow capture, manipulate, process and display of georeferenced data integrated with genetic resource database for operations such as query and statistical analysis, visualization and geographic representation. GIS based several spatial tools have been developed that model species’ ecological niches finding a relationship between crop or variety with a set of environmental parameters and useful for planning exploration, evaluation trials, in situ and ex situ conservation sites. GIS technologies have direct practical application in elucidation of genetic, ecological and geographic patterns in the distribution of crops and wild relatives; mapping of richness, diversity, distribution of useful traits and, location of areas with complementary diversity; gene bank information management and strategies for future explorations and gap analysis; selection of suitable accessions/sites for ex situ evaluation; searching germplasm for abiotic stress tolerance and developing core collections. With the increasing availability of high- speed computers and software development in the area of GIS tools specific to PGR management increasing trend in application of these is expected. Apart from ecogeographic survey for locating diversity and germplasm collection and design, management and monitoring of in situ reserves, introduction of new varieties, and development of core collection, locating gene donors for biotic and abiotic stresses are the areas to be benefited with the GIS application.

Keywords: GIS, genetic resource, distribution, diversity, core collection, gap analysis, mapping

Chhattisgarh, the 26^th state of the Indian Union came into existence on November 1^st, 2000. The state is geographically situated in the central part of India, between the latitudes of 17° 46' N - 24° 5' N and the longitudes of 80° 15' E - 84° 20' E. Its proximate position with the Tropic of Cancer has a major influence on its climate. The total geographical area is around 137.90 lakh ha of which cultivable land area is 46.77 lakh ha and forest land area is 63.53 lakh ha with more than 2.55 crore population. In Chhattisgarh region about 22% of net cropped area was under irrigation. About 80 percent of the population in the state is engaged in agriculture and 43 percent of the entire arable land is under cultivation. Paddy is the principal crop and the central plains of Chhattisgarh are known as rice bowl of central India. Other major crops are coarse grains, wheat, maize, groundnut, pulses and oilseeds.

Importance of Maize in Chhattisgarh

Earlier maize was mainly cultivated in Surguja and Bastar division of Chhattisgarh but now it is emerging as main cash crop in entire Chhattisgarh state. There had been an increase of 20 per cent in maize crop acreage in Chhattisgarh during the past 10 years. Now the farmers of the area are cultivating maize in lines, applying atrazin weedicide, full dose of chemical fertilizers, etc. They are willing to buy the hybrid seed for cultivation from the market and taking maize as green cob and also utilizing as green fodder. Maize threshers have been purchased by some farmers in the region which is an indicative of large maize production.

For industrial utilization of the maize Chhattisgarh state has “Raja Ram Maize Factory” in Rajnandgaon district. They are producing and supplying Maize starches, liquid glucose, dextrose mono hydrate, dextrin, maltose liquid, malto dextrin, maize oil, maize gluten, maize grit, maize husk etc. But most of the maize production is used as poultry feeds in the state. Traders purchase it directly from the farmers’ fields in the villages. It is also exported to the neighboring states either as grain or green cob. Around 10-15% is retained by the farmers for own consumption and seed purpose.

Bihar is an important maize growing state in India after Karnataka, Andhra Pradesh, Telangana, Rajasthan and Maharashtra, where it is cultivated during all season. However, the yield of maize is much higher during Rabi and summer seasons than the Kharif. Due to climate change and other factors, the yield of maize is likely to further decline during the Kharif season. However, the cultivation of maize in Bihar during the Rabi season will be much more profitable as compared to wheat due to rise in temperature. There is need to develop maize varieties which can with stand biotic and abiotic due to changing climate factors.

Decadal trends of maize area, production and stresses yield in the Bihar from 1950–2015.

Maize (Zea mays L., 2n=20) is a cereal crop that is grown widely in more than 165 countries in a range of agro-ecological environments. Even in Asia, the rapid increase in maize acreage in the last decade is an indication that it is winning the battle as compared with rice. The Asian region will see itself as a major global player in the near term. In the past it was mainly confined to food in India and many other countries however, now it has become the industrial crop. Maize has several industrial applications and more than 1000 products are being developed from maize in India and around 3500 products in USA and other countries. It is a raw material for many of the important industries viz. pharma, textile, paper, film, tyre food, processing, packing and biofuel, etc. The growth rate of poultry, livestock, fish, wet and dry milling industries are very high therefore, maize demand will continue to increase in year to come.

Global Maize Scenario

Globally, maize is primarily used as feed livestock and has many industrial uses; however in many developing countries it is still used as a food crop. Small-scale farmers in both sub-Saharan Africa and Mesoamerica generally grow maize as a food crop for household consumption and for saline urban markets. Maize is particularly important in the diets of the rural and urban poor in sub-Saharan Africa and Latin America. Globally, maize is grown in 165 countries in a total of 185.1 million hectares area with 1018.1 million tones of production and 5.52 tonnes/ha productivity (Anonymous 2015-16). Almost 70% of the total maize production in the developing world is coming from low and lower middle income countries. In Asia, maize has recorded the fastest annual growth (around 4%), as compared to other cereals. Maximum maize production was in USA (353.7 million tonnes) followed by China (218.6 million tonnes) and Brazil (80.3 million tonnes) (Fig. 1), while the area under maize cultivation was in China (36.3 million hectare) followed by USA (35.5 million hectare) and Brazil (15.3 million hectare) (Fig. 2). The average world maize productivity is 5500 kg/ha, but the highest productivity of maize was achieved in USA (9970 kg/ha) followed by Canada (9591 kg/ha) and France (8137 kg/ha) (Fig. 3).

The ever mounting population in 21^st century is a great challenge for the researchers to provide ample food and that has to be achieved within the context of existing challenges such as deteriorated arable land along with increasing adverse affects of changing climate. There is demand to increase food production to the tune of 70% by 2050 (Wani and Sah, 2014). Although major crops have achieved good progress, vulneRability to climatic variability emerged as a serious concern in crop improvement which could be attributed to higher sowing densities that in turn lead to more competition for water and nutrients. Abiotic stresses can be considered as major yield restraining factors among different crops. The projected estimations for changes in abiotic stresses such as drought, water logging and heat reveals far serious concerns for crop productivity (Qin et al., 2011; Bailey-Serres et al., 2012). Therefore, the concern of global food security in the era of climate change has compelled plant scientists in different crops to shift to breeding for climate resilient genotypes. Maize, being a hardy crop has an inherent potential to perform well under sub-optimal environments with minimum crop management (Kole et al., 2015). Abiotic stresses such as drought, heat and water logging affects maize yield adversely.

Although, conventional breeding approaches have exploited its fullest potential for production of elite maize hybrids but still little success attained for breeding climate resilient genotypes or varieties owing to the fact that stress tolerance is multi-genic or quantitative in nature. Therefore, the best option is to utilize the molecular breeding along with the conventional approaches for development of climate smart varieties.

Raster sub-setting is done to select the desired area or bands of the raster image on which the user wants to perform analysis. Raster sub-setting is done in two ways:

Spectral subset: Spectral sub-setting is done to extract few desired bands from the multiband raster image which are required for analysis.

Spatial subset: Spatial sub-setting is done to minimize the area or extent of raster image to the desired area or extent for further analysis.

Raster sub-setting in R is done by functions available in the ‘raster’ package. The following packages are required in this chapter:

Vector data analysis is performed to convert raw input vector data to output that provides new and meaningful information which ultimately supports decision making and disclose hidden patterns. There are various techniques to analyse vector data like buffering, intersect, union, and so on. Some of the most commonly used techniques with their R-code examples are explained in this chapter.

First of all, you need to import all the packages which are required for performing this exercise. These packages include rgdal and sp for importing and re-projecting vector data as well as raster and rgeos for performing vector analysis operations.

The calculation of raster data statistics is very essential before performing some geoprocessing operations. Raster data statistics involve knowing the distribution of pixel values in a band, comparing the pixel values of two bands, extracting values of all bands for a particular geographical location or point, and computing statistics like mean, median, standard deviation, etc. at pixel level across all bands of raster dataset.

In R, codes to perform raster data statistics are present in raster package. The visualisation of raster data statistics can be done by rasterVis package. So, we need to import these packages in R in order to perform this exercise.

Bonsai is a Japanese art form using miniature trees grown in containers. The first documented evidence of an oriental word for container planting emerged approximately 1600 years ago in China. Bonsai is a Japanese pronunciation of the earlier Chinese term pen zai. A bon is a tray-like pot typically used in bonsai culture. The purposes of bonsai are primarily contemplation (for the viewer) and the pleasant exercise of effort and ingenuity (for the grower). Bonsai is not intended for production of food, for medicine, or for creating yard-sized or park-sized gardens or landscapes. Instead, bonsai practice focuses on long-term cultivation and shaping of one or more small trees in a single container.

The practice of bonsai is sometimes confused with dwarfing, but dwarfing more accurately refers to research and creation of plant cultivars that are permanent, genetic miniatures of existing species. Bonsai does not require genetically dwarfed trees, but rather depends on growing small trees from regular stock and seeds. Bonsai uses cultivation techniques like pruning, root reduction, potting, defoliation and grafting to produce small trees that mimic the shape and style of mature, full-sized trees.

Bonsai can be created from nearly any perennial woody-stemmed tree or shrub species. Which produces true branches and can be cultivated to remain small through pot Some species are popular as bonsai material because they have characteristics, such as small leaves or needles that make them appropriate for the compact visual scope of bonsai. Some of the plants highly suited for making bonsai

7.1 The Formula Palette

By clicking on the equals sign in the formula bar a drop – down panel called the formula palette appeared.

Consider an example, type number 25 in cell A1 and move the cell pointer to cell B2. type or click the equal sign in the formulabar. Adrop – down panel will display formula result = and wait for further inputs. Enter sqrt result to 5 at B2.

The dialog box divides into parts as

(a) Name of the function at the top left of the argument entry box.

(b) Below of this there is the definition or description of the function.

(c) Next, there is an entry explanation.

(d) Formula result.

Things to remember: Any statistical or mathematical function can be activated with = (equal to) sign.

The fore limb is termed as pectoral limb or thoracic limb (Fig. 5-1). It is attached to the thorax by means of muscles of pectoral girdle (shoulder girdle). It is composed of four major segments, the shoulder girdle, arm, forearm and manus. The skeleton of shoulder girdle is formed by the shoulder bone, the scapula. The arm is formed by the arm bone the humerus. The forearm is formed by two bones the radius and ulna; and the manus is formed by the carpus consisting of six short bones –the carpal bones arranged in two layers, the metacarpus consisting of one large and one small metacarpal bones and the digits consisting of six short bones the phalanges and six small sesamoids arranged in two rows for each limb.

Shoulder girdle

The shoulder girdle (thoracic girdle or pectoral girdle) in general is composed of the scapula, coracoid and clavicle. In ruminants the scapula is well developed, the coracoid is in the form of a small rounded process fused with the ventral end of the scapula and the clavicle is absent or in some subjects it occurs embedded in the brachiocephalicus muscle cranial to the point of the shoulder. But this possibility is very rare. Hence, in ox only scapula is considered as the bone of shoulder girdle.

Scapula

The scapula is a flat triangular bone applied obliquely ventrad and craniad against the cranial part of the lateral wall of thorax. Its long axis extends from the fourth thoracic spine to the sternal end of the first rib. It presents two surfaces, three borders and three angles.

Embry Transfer Technology (ETT)

Definition: The process of removing one or more embryos from the reproductive tract of a donor female and transferring them to one or more recipient females.

Parasite- The word parasite is derived from the Greek. Para- beside and sitos- food. Parasites are those living organism which reside on or inside the body of some other species of living organism.

Host- Those organisms which provide food shelter and conducive environment to parasite for their growth, development and reproduction. e.g. Tape worm in small intestine of man and animals.

Disease = dis + aise (see + ease) old French word

Transmission- Movement of biological agents (Virus, Bacteria, Rickettsial, Fungi & Parasites) from one place to another place via vector or vehicle/ tools

Vector- Latin word- bearer

Vector is a living organism (usually an arthropod) which transfers infective forms of a parasite from one host to the other.

Veterinary physiology deals with the study of normal functions of animal systems. It includes the study of how animals work and the physical and chemical processes that occur within animals. The examples of various biological processes in animals include gas exchange, blood and circulation, osmoregulation, digestion, nervous and muscle systems, respiration, growth, reproduction, endocrine function and how animals behave and function in different environmental conditions. This also includes the possible manipulation of the reproductive processes by means of hormone manipulation techniques for more efficient livestock and poultry production.

Abstract

Livestock sector has gained momentum world over with consistently increasing market demand for live stock products. India with annual 171 million tons of liquid milk production, 74 billion egg production, 3.8 million tons of poultry meat and 11.50 million ton of fish production offers enormous opportunities for women agri-preneurs to venture into this area. Micro-enterprise development related to livestock rearing activities like dairy farming, sheep husbandry, goatry, poultry, livestock feed production, vermin-composting and value added product development and production are the important enterprises in which women can utilize their technical skills. Finance for infrastructure and small scale agro-processing units are requisites to success of rural women entrepreneurs as these will help them to enhance their competency to use raw materials from the farm and livestock to earn substantial income. Rural women entrepreneurs are facing tough competition from the large scale organizations and urban entrepreneurs where governmental interventions are essential. The women producers are not collective in their approach for marketing their products because they are scattered and mostly uneducated. The women entrepreneurs are heavily dependent on middlemen for marketing of their products who pocket large amount of profit. Hence, government should take steps to provide market information of different products and finance to the rural entrepreneurs at concessional rates.

Abstract

Most of the vegetables available in the market contain large quantity of pesticide residue. This has created serious health problems among the people. Self-sufficiency in safe to eat vegetable production can be achieved either by commercial production or better farming by family in kitchen garden. As quality control mechanism is not strong and well established, the produce from commercial farming can’t be assured as safe to eat product. The continuous effort taken by our centre and other existing systems in the state for the last six years have made the people aware about the quality of vegetables. In Kerala, most of the families, especially in town and nearby areas are having only 3 to 10 percent of land. The space they can spare for vegetable production either on the ground or on roof top is hardly 10 to 40m². Pest and disease attack is another issue in Kerala. Hence our centre gave importance for the design and development of 10m² /20m² /30m² poly-kitchen garden which could accommodate 160 to 350 plants (almost all pest susceptible crops required for a family can be accommodated inside these structures.) suitable for a family by utilizing multi-tier grow bags (one multi-tier grow bag can accommodate 35 to 50 plants), grow bags and troughs. In these structures, cultivation practices can be done even during night without the fear of snake and mosquitoes by fitting a fluorescent lamp. This technology was approved by Government of Kerala and declared 75% subsidy for establishing this full facility for a family. In order to popularize this technology among the public, we had conducted many training programmes and empowered the women (house wife/employed woman) in vegetable production and to make their mindset to ensure a kitchen garden (either a conventional type grow bag kitchen garden or poly-kitchen garden) in their house plot. When we started working with this goal (in 2013, when project was started), < 20% of required vegetables for the state was produced in the state. On account of our continuous effort, by the year 2016, state managed to pick up its vegetable production by 64.5%

Citrus (Citrus spp.)

Citrus is an important fruit crop and ranks third in area which is followed by mango and banana. They are grown in 105,396 hectares in India. Among the oranges, mandarin oranges, limes and sweet oranges are very popular while lemons, grape fruits, pummelos, sour and bitter oranges are of minor importance. The Citrus spp. are grown in larger extent in the states of Maharashtra, Karnataka, Kerala, Tamil Nadu, Andhra Pradesh, Punjab, Haryana, Rajasthan, Assam, Orissa and Bihar.

Nematode menace in citrus gardens are very much realised. In 1912 the citrus nematode, Tylenchulus semipenetrans was reported from California and found to cause ‘slow decline’ disease. More than 30 genera of plant parasitic nematodes are associated with the Citrus spp. Among them, Tylenchulus semipenetrans, Radopholus citrophilus, Meloidogyne spp. Pratylenchus spp. Xiphinema spp. and Hoplolaimus spp. are often associated with the crop.

Spectacular productivity gains have been achieved in wheat and rice in south and south-east Asia and also several other developing countries in Latin America and central Asia due to introduction of dwarfing genes in these two crops purely through conventional plant breeding approaches and these developments were christened as “Green Revolution” (Reynolds and Borlaug, 2006). The wheat breeding progrmme was being spearheaded by Norman Borlaug at CIMMYT (International Maize and Wheat Improvement Centre, Mexico) supported by Sanjay Rajaram and the rice breeding programme was under leadership of Gurdev Singh Khush at IRRI (International Rice Research Institute, Manila, Philippines) coinciding with these exciting developments during mid-sixties to mid-seventies. In recognition of these quantum jumps in yield of wheat and rice, Borlaug was awarded Nobel Peace Prize for Peace in 1970. Later on World Food Prize was instituted by joint efforts of Borlaug and his colleagues to honour Agricultural Scientists and others on pattern of Nobel Prize who had made significant contributions to sustainable food production and food and nutritional security globally. M. S. Swaminathan happened to be Director General, Indian Council of Agricultural Research when Green Revolution was taking roots in India and because of his enormous contributions to provide effective leadership to ensure that Green Revolution happened in India, M. S. Swaminathan is credited as “Father of Green Revolution in India” and he was the first recipient of World Food Prize in 1987 for spearheading the introduction of high-yielding wheat and rice varieties in India. G. S. Khush along with Henry Beachell received 1996 World Food Prize for achievements in enlarging and improving the global supply of rice during a time of exponential population growth and Sanjay Rajram was the 1914 World Food Prize recipient for his scientific research that led to huge increase in world wheat production.

Biotech crops or genetically modified (GM) crops or the transgenic crops are those crop plants into which certain genes have been introduced from unrelated sources beyond the boundary of sexual compatibility using techniques which bypass the normal sexual cycle. The transgenic production technology uses recombinant DNA technology where a recombinant DNA molecule is a vector into which the desired DNA fragment has been inserted to enable its cloning in an appropriate host. The recombinant DNA technology has opened up the flood gate of plant biotechnology to produce plants which are equipped with novel genes to produce products never heard of that a plant will do. Now transgenics in several crops have been commercialized globally. The importance and potential of GM crops can be realized from the fact that acreage under such crops at global level has reached to 189.8 million ha covering 24 countries in 2017. One can have a feel of this huge acreage under commercialized GM crops globally if it is compared with about total cultivated area of 143 million ha in India.

Over the last 30 years field of agricultural biotechnology has expanded rapidly due to greater understanding of DNA as the chemical double helix code from which genes are made. Genetic engineering is one of the modern biotechnology tools that are based on recombinant DNA technology. The term genetic engineering, often interchanged with terms such as gene technology, genetic modification, or gene manipulation, is used to describe the process by which the genetic makeup of an organism can be altered using “recombinant DNA technology.” This involves the use of laboratory tools and specific enzymes to cut out, insert, and alter pieces of DNA that contain one or more genes of interest. The ability to manipulate individual genes and to transfer genes between species that would not readily cross is what distinguishes genetic engineering from traditional plant breeding and opens up a huge opportunity to create crop plants equipped with desirable genes from the sources which cannot be sexually crossed. With conventional plant breeding, there is little or no guarantee of obtaining any particular gene combination from the millions of crosses generated. Undesirable genes can be transferred along with desirable genes or while one desirable gene is gained, another is lost because the genes of both parents are mixed together and re-assorted more or less randomly in the offspring. These are the major limitations of conventional crop breeding.

Introduction

The term biological control was first used in scientific literature in 1914. Baker and Cook (1974) described biological control as “reduction of inoculum density or disease producing activities of a pathogen or parasite in its active or dormant state, by one or more organisms, accomplished naturally or thoroughly manipulation of environment, host, or antagonists or by mass introduction of one or more antagonists.”

Certain genera of fungi have greater potential for being effective bio-control agents eg. Trichoderma, Gliocladium, Chaetomium; entomogenous fungi as Entomophthora, Beauveria, Metarrhizium, Hirsutella; Nematophagous viz., Catenaria, Zoopage, Stylopage, Paecilomyces and predaceaus fungi like Arthrobotrys, Dictylella, Dactylaria and Nematoctonus (Narain, 2018). Biopesticide formulations based on these fungi are also called as “Microbial pesticides”.

Abstract

Palms are generally grown commercially in tropical climate. But some of the palms like coconut, areca nut and palmyra palm are cultivated successfully in West Bengal, Orissa, Assam, and some pockets of Bihar that lies under sub tropics of India.Due to unsuitable climatic factor their production is more affected by abiotic and biotic stress including different kinds of diseases. The important disease are bud rot, basal stem end rot, nut shedding,stem bleeding in coconut, mahali disease, foot rot, stem breaking in arecanut and palmyra palm in the region have negligible incidence of diseases. These destructive diseases are the major constrain in production and causes severe yield loss in these palm fruits. Therefore effective management strategies are required by continuous monitoring the incidence and severity of these diseases caused by different pathogens.

Integrated disease management is the most accepted strategies for sustainable crop production that involves the holistic approach integrating cultural, physical, mechanical, chemical and biological means to control the disease. However, results of the disease management trials depend upon soil condition, age of the crop, stage of disease development and weather parameters of that particular area. Although it is impossible to manage a field free of pathogen but considerable reduction of the disease can be achieved through a proper integrated disease management system. Thus the causes and remedy of the diseases prevalent mainly in palms particularly in subtropical conditions has been reviewed for better management and sustainable production.

Hunter and Mohler discovered the isozymes. In 1959 Markert and Moler introduced the concept of isozymes, which they defined as the different molecular forms in which proteins may exist with the same enzymatic specificity (Buth 1984). This means that different variants on the same enzymes have identical or similar functions and are present in the same individual. As such, their importance for understanding gene action in development and differentiation was exploited during the1960s in both animals and plants. Nevertheless, isozymes played a minor role in research on plant biochemistry until 1966 when genetic polymorphism for isozymes within the same population was discovered (Stebbins 1989, Wendel 1989). That revealed the possibility for population genetics to make precise quantitative estimates of genetic variability based upon one parameter of the molecular structure of the primary products of the genes themselves.

Plant population genetics were not long in following their zoological colleagues and the investigation of both animals and plants increased explosively. This application, however, necessitated a partitioning of the isozyme concept, since the relevant isozyme subset, defined by Prakash (Buth 1984) as the variant proteins produced by allelic forms of the same locus, to avoid the now common confusion with isozymes which are the various polymer produced from monomers specified by different loci. The development of genetic distance or similarity coefficients (Lukasová 1985) allowed the summarization of isozyme data for intersample comparisons and so quantified isozyme data were soon applied to comparative studies of taxa.

QTL Traits

Polygenic inheritance, also known as quantitative or multifactorial inheritance refers to inheritance of a phenotypic characteristic (trait) that is attributable to two or more genes and their interaction with the environment. Unlike monogenic traits, polygenic traits do not follow patterns of Mendelian inheritance (qualitative traits). Instead, their phenotypes typically vary along a continuous gradient depicted by a bell curve. Though not necessarily genes themselves, quantitative trait loci (QTLs) are stretches of DNA that are closely linked to the genes that underlie the trait in question. QTLs can be molecularly identified (for example, with PCR or AFLP) to help map regions of the genome that contain genes involved in specifying a quantitative trait. This can be an early step in identifying and sequencing these genes.

DNA Sequencing

DNA sequencing is the determination of the precise sequence of nucleotides in a sample of DNA. Sequencing can be done on a short fragment of DNA to cover the entire genome. The maps thus constructed using the nucleotide sequences in the correct order is called as sequence map.

In 1977, twenty-four years after the discovery of the structure of DNA, two separate methods for sequencing DNA were developed: the chain termination method (Sanger et al., 1977) and the chemical degradation method (Maxam and Gilbert, 1977). Both methods were equally popular to begin with, but, for many reasons, the chain termination method is the method more commonly used today. In chemical degradation method, chemicals specific to each base remove the last base, which has been labelled. The method uses toxic chemicals which required high care while handling.

In chain termination method, DNA polymerase extends a DNA strand in which dideoxynucleotide becomes incorporated terminating the chain extension (phosphodiester formation) at the 3’OH site making an array of fragments differing in length. This method is based on the principle that single-stranded DNA molecules that differ in length by just a single nucleotide can be separated from one another using polyacrylamide gel electrophoresis.