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Lablab purpureus usually knowna s Dolichus bean, Hyacinth bean or Field bean belonging to the family fabaceae, one of the most ancient crops among cultivated plants. It is a bushy, semi-erect, perennial herb, showing no tendency to climb. It is mainly cultivated either as a pure crop or mixed with finger millet, groundnut, castor, corn, bajra or sorghum in Asia and Africa. It is a multipurpose crop grown for pulse, vegetable and forage. The crop is grown for its green pods, while dry seeds are used in various vegetable food preparations.

Season:Seed is very sensitive to weather. A grain crop can be sold for a lower price even if it damaged by rain. But a seed crop, if affected will lead to low seed quality. Hence selecting the right season is necessary. Generally, the seed should mature in cool dry climate. Seasons should be selected with this idea in mind. In Tamil Nadu the best seed crops are grown during March--April and September - October as the seeds mature during the cool months of January - February.

Botanical description

Cowpea belong to genus Vigna and species unguiculata (L) Walp (Syn V. sinensis Savi) of the family Leguminosae sub family Fabacae.

Floral biology

The flowers of cowpea are hermaphrodite. Self-pollination is effected though with some cross-pollination.

Climate and Soil

Cowpea is a warm season crop, and therefore it can be grown both in spring and in rainy seasons in the plains of India. It cannot tolerate cold weather, heavy rainfall and water logging.

Bhendi is known by many local names in different parts of the World. For example it is called Lady’s finger in England, Gumbo in USA, bhendi in India Okra (Abelmochus esculentus L. 2n= 1 30) belongs to the family Malvaceae. Origin of okra is West Africa. Okra plant is an erect, herbaceous annual, 1-2 meter tall and forms fairly heavy tap root.

Chilli or Pepper (Capsicum Sps.) originated in South America and spread into the New World tropics before subsequent introduction to Asia and Africa. Chillies are now widely grown throughout the tropics, sub-tropics and warmer temperature region of the world. The genus Capsicum is a member of the family Solanaceae.

The brinjal, eggplant or aubergine (French name) has originated in the Indian sub-continent and China (Thomson and Kelly, 1957, Purewall, 1957 and Martin and Rhodes, 1979). Brinjal is an important vegetable crop of the Far East, Bangladesh, India, China and the Philippines. Brinjal belongs to the family Solanaceae and is known under the botanical name Solanum melongena L. (2n = 24). There are 3 main botanical varieties under the species melongena(Chowdhury, 1976). The round or egg-shaped cultivars are grouped under var. esculenturn, the long slender types are included under var. serpentintumand the dwarf brinjal plants are put under var. depressum.

Tomato is one of the most popular and widely grown nutritious vegetable in the world. Tomato (Lycopersicum esculentum Linnacus Karst.) belonging to the family Solanaceae is one of the most nutritious and remunerative vegetable crop. It is the world’s important vegetable next to potato. The crop is cultivated throughout the year. In Northern plains, the crop is cultivated during autumn, spring and summer. In South India, the crop is grown in June – July, October – November and January – February. The optimum season for seed production in southern India is October – December. Nursery raised in late October and transplanted in the first week of December will produce a good seed crop.

A

Abnormal seedling: Abnormal seedlings are those seedlings which do not show the capacity for continued development in to normal plants when grown in good quality soil under favourable conditions of water supply, temperature and light.

Abortion: Loss of reproductive structures (e.g. a flower or an ovule) during development or arrest of development of any organ so that it remains imperfect or fails to reach maturity.

Absolute humidity: The amount of water vapour present in a given volume of atmosphere, usually expressed in g water per kg dry air, or g water per cubic meter air.

Introduction

Seed as an input is the precursor for agricultural development as it alone can guarantee 20-30 per cent share of crop productivity (Koudinya and Kumar, 2014). Rigveda, the world’s most ancient scripture available, prescribes the importance of seeds as “Subeejam Sukshetre Jayate Sampadyate” which literally means, “A good seed in a good field can lead to the prosperity and posterity of the entire human race”. Seed production is indeed important to take care of a country’s food and nutritional security needs. At the same time, seed export across countries is vital for ensuring competitiveness in the domestic seed industry besides generating employment and valuable foreign exchange which in turn can be used for scaling up the seed sector’s efficiency itself (Poonia, 2013). As a matter of fact, seed trade is one of the reasons for huge advances made in the Indian seed industry through development and exchange of genetic transformation, marker-assisted breeding and nanotechnology (Nandi et al., 2013). As of 2014-15, global seed industry has reached USD 45 billion in which international seed export alone was worth USD 10 billion. Further, with the estimated growth rate of 9.2 per cent during 2015-2020, the world seed business is expected to be over USD 92 billion. Presently, USA, China, France, Netherlands and Brazil are the top markets comprising more than 66 per cent of the global share in seed trade. Corn, soybean and vegetables account for more than 75 per cent of the total global seed market volume. As of 2014-15, the value of the Asian vegetable seed market was USD 6.75 billion in which China had a major share (41 per cent) and the Indian share was around 7 per cent. Moreover, the world vegetable seed market alone is expected to grow at the rate of 7 -8 per cent per annum and reach USD 8.8 billion by the year 2020 (Parashar and Kumar, 2016).

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.

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.

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).

What is seed?

“A seed is an embryo, a living organism securely fixed in the supporting or the food storage tissue.”

A true seed is defined as “Structurally a true seed is a fertilized matured ovule, consisting of an embryonic plant, a store of food and a protective seed coat, a store of food consists of cotyledons and endosperm”. In broad sense, “seed is a material which is used for planting or regeneration purpose”. Scientifically, “seed is a fertilized matured ovule together covered with seed coat is called seed” or “it is a propagating material i.e., part of agriculture, sericulture, silviculture and horticultural plants used for sowing or planting purpose”.

The business of Seed Technology is to protect this biological entity and look after its ‘welfare’, while the focus of Food Technology is on the second component – the supporting tissue.

Introduction

Synthetic seeds are defined as artificially encapsulated somatic embryos, shoot buds, cell aggregates, or any other tissue that can be used for sowing as a seed and that possess the ability to convert into a plant under in vitro or ex vitro conditions and retained its potentiality also after storage (Capuano et al., 1998). In other words, synthetic or artificial seeds defined as somatic embryos engineered seed used in the commercial propagation of plants (Gray and Purohit, 1991; Redenbaugh, 1993).

Artificial seeds have great potential for large scale production of plants at low cost as an alternative to true seeds (Roy and Mandal, 2008). An artificial seed is often described as a novel analogue to true seed consisting of a somatic embryo surrounded by an artificial coat which is at most equivalent to an immature zygotic embryo, possibly at post-heart stage or early cotyledonary stage (Bekheet, 2006). There are various advantages of artificial seeds such as better and clonal plants could be propagated similar to seeds, preservation of rare plant species extending biodiversity could be realized, and more consistent and synchronized harvesting of important agricultural crops would become a reality, among many other possibilities (Khor and Loh, 2005). In addition, ease of handling, potential long-term storage and low cost of production and subsequent propagation are other benefits (Bekheet, 2006).

Introduction

Since beginning of this century genetic diversity of agricultural crop has been lost due to several reasons (Marla, 2012). Genetic erosion is caused by human intervention, mono culture, green revolution especially due to commercialization of plant breeding. So there is urgent need to collect, conserve plant genetic & genomic resource for further use.

A seed bank stores seeds to preserve genetic diversity. There are many reasons to store seeds. One reason is to have on-hand the genes that plant breeders need to increase yield, disease resistance, drought tolerance, nutritional quality, etc. of plants used in agriculture (i.e., crops or domesticated species). Another reason is to forestall loss of genetic diversity in rare or imperiled plant species in an effort to conserve biodiversity ex situ and in situ. Many plants that were used centuries ago by humans are used less frequently now and seed banks offer a way to preserve that historical and cultural value. Collections of seeds stored at constant low temperature and moisture guard against loss of genetic resources that are otherwise maintained in situ or in field collections. These alternative ‘living’ collections can be damaged by natural disasters, outbreaks of disease or war. Seed banks are considered seed libraries and contain valuable information about evolved strategies to combat plant stress or produce novel products. The work of seed banks spans decades and even centuries. Most seed banks are publicly funded and seeds are usually available for research that benefits the public.

Archaeobotany

Botany as far as it is relevant in archaeology mainly denotes all types of ancient organic material (in particular ancient plant remains) collected from excavation sites. The deliberate study of the interrelationship between humans and plants and the environmental context in which this occurred has been called archaeobotany.

Introduction

Germination is the process by which a plant grows from a seed or similar structure. The most common example of germination is the sprouting of a seedling from a seed of an angiosperm or gymnosperm. Quick germination is the various ways and means that really fastened the process of seed germination. Through various ways, it is possible to reduce the time of germination by 70 per cent and also the success rate of germination can also be doubled.

Introduction

Organic seeds are produced by purchasing conventional non-treated seeds and growing them on organic plot / farm for one season without the use of any synthetic chemical. The seeds harvested are then sold on to organic farmers as organic seeds.

Over 98% of sprayed insecticides and 95% of herbicides reach a destination other than their target species, because they are sprayed or spread across entire agricultural fields. Runoff can carry pesticides into aquatic environments while wind can carry them to other fields, grazing areas, human settlements and undeveloped areas, potentially affecting other species. Other problems emerge from poor production, transport and storage practices.

Production of organic seeds without the use of pesticides like herbicides (weeds), insecticides (insects), fungicides (fungi), nematocides (nematodes), and rodenticides (vertebrate poisons) is a matter of skill and expertise. For this purpose, the seeds used for planting, the soil where they are planted, the water used for irrigation and even the air, need to be kept free of pesticides in order to prevent their contamination.

Seed

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.

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.

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.

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

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).

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.

Seed marketing is one of the most vital components of seed technology. Broadly, it includes such activities as production, processing, storage, quality control and marketing of seeds. In the narrow sense, however seed marketing refers to the actual acquisition and selling of packed seeds, intermediate storage, delivery and sales promotional activities. Seed marketing comprises the following:

1. Demand forecasts (assessment of effective demand)
2. Marketing structure
3. Arrangements for storage of seeds
4. Sales promotional activities
5. Post-sales service
6. Economics of seed production and seed pricing

A bill to provide for regulating the quality of seeds for sale, import and export and to facilitate production and supply of seeds of quality and for matters connected therewith or incidental thereto. Be it enacted by Parliament in the Fifty-Fifth Year of the Republic of India as follows

Aims and Objectives

It has become evident that in order to achieve the food production targets of the future, a major effort will be required to enhance the seed replacement rates of various crops. This would require a major increase in the production of quality seeds, in which the private sector is expected to play a major role. At the same time, private and Public Sector Seed Organisations at both Central and State levels, will be expected to adopt economic pricing policies which would seek to realise the true cost of production. The creation of a facilitative climate for growth of a competitive and localised seed industry, encouragement of import of useful germplasm, and boosting of exports are core elements of the agricultural strategy of the new millennium.

Biotechnology will be a key factor in agricultural development in the coming decades. Genetic engineering/modification techniques hold enormous promise in developing crop varieties with a higher level of tolerance to biotic and abiotic stresses. A conducive atmosphere for application of frontier sciences in varietal development and for enhanced investments in research and development is a pressing requirement. At the same time, concerns relating to possible harm to human and animal health and bio-safety, as well as interests of farmers, must be addressed.

Globalization and economic liberalization have opened up new opportunities as well as challenges. The main objectives of the National Seeds Policy, therefore, are the provision of an appropriate climate for the seed industry to utilize available and prospective opportunities, safeguarding of the interests of Indian farmers and the conservation of agro-biodiversity. While unnecessary regulation needs to be dismantled, it must be ensured that gullible farmers are not exploited by unscrupulous elements. A regulatory system of a new genre is, therefore, needed, which will encompass quality assurance mechanisms coupled with facilitation of a vibrant and responsible seed industry.

Preliminary

1. Short title and extent

1. This Order may be called the Seeds (Control) Order, 1983
2. It extends to the whole of India
3. It shall come into force on the 30th December, 1983

Part I - Preliminary

1. Short title: These rules may be called the Seeds Rules, 1968
2. Definitions: In these rules, unless the contest otherwise requires.

An Act to provide for regulating the quality of certain seeds for sale, and for matters connected therewith. It enacted by Parliament in the Seventeenth Year of the Republic of India.

1. Short Title, Extent and Commencement

• This Act may be called the Seeds Act, 1966.
• It extends to the whole of India.
• It shall come into force on such date as the Central Government may, by notification in the Official Gazette, appoint, and different dates may be appointed for different provisions of this Act, and for different States or for different areas thereof.

History and development of seed Industry in India can be discussed under two heads

1. Pre-independence development.
2. Post-independence development.

Seed Health Testing

Science of determining the presence or absence of disease causing agents such as fungi, bacteria and viruses and insects in the seed samples.

Seed Borne disease

The seed primordial or the maturing seed may be infected either (i) directly from the infected plant through the flower or fruit stalk and the seed stalk or directly from the seed surface, or (ii)infection from outside may be introduced through stigma or ovary wall or pericarp, and the flower or fruit stalk, and later through the seed coat. A pathogen may penetrate several of these parts of the seed and in turn infect them. The infestation /contamination of the seed may occur during harvesting, threshing and processing. Visualizing the importance of seed borne diseases the Central Seed Certification board has prescribed certification standards for foundation and certified seed for several diseases.

The pathogen may carry with the seeds in three ways.

• Admixture: Pathogens are independent of seeds but accompany them. They are mixed with health seeds during threshing.
• External:The pathogen may be present on seed surface as spores, oospores and chlamydospores.
• Internal: Pathogens establish within the seed with definite relationship with seed parts.

Post-harvest deterioration primarily means the loss of commodity after harvest. It is one of the serious problems for producers, distributors and consumers. Post-harvest deterioration of perishables is the spoilage of fruits and vegetables after harvesting. Perishables are the feed commodities with moisture content between 50 and 90%. Fruits with the size of 5 g to 5 kg or more, high to very high rate of respiration, high generation of heat, soft texture, easily damageable nature and shorter shelf life are more prone to the microbial damage. The post-harvest losses are caused either by pathological, physiological and mechanical means or combination of all these. These perishables because of having minerals, vitamins, and photochemicals (essentially required for the human health) become victim to the several biotic and abiotic factors easily. Once these fruits are detached from the plant are deprived of essential ingredients as hormones, nutrients, water and other requisites. These biotic and abiotic factors apart from rendering the produce unfit for human consumption reduce the aesthetic value, substantial decrease in food value and also organoleptic quality of the vegetables. The fleshy produce are prone to the exogenous agencies such as fungi, bacteria, etc. as well as other endogenous factors such as respiration, senescence, etc. which may lead to poor quality of the produce and also affect market quality. These perishables continue to respire and may carry out various biochemical activities, leading to ripening subsequently to senescence and making them more susceptible to microbial damage. In addition, tropical conditions prevailing in India, which are characterized by high temperature conditions, are optimal for fungal and bacterial infections. In India, the post-harvest losses of fresh fruits and vegetables are estimated to be about 30%. The post-harvest losses have been recorded are 5-20% at farmer’s field due to pre-harvest infection and sorting, 15-20% due to faulty packaging, 30-40% during transportation and 30-40% during marketing.

Plant viruses, like all other viruses, are obligate intracellular parasites that do not have the molecular machinery to replicate without the host. The plant viruses are defined as viruses pathogenic to higher plants. The discovery of plant viruses causing disease is accredited to Beijerinck who determined in 1898 that the plant sap obtained from tobacco leaves with the mosaic disease remained infectious even after passing through a filter. This was in contrast to bacteria, which were retained by the filter. Beijerinck referred to the infectious filtrate as a contagium vivum fluidum, thus, he used modern term virus.

Viruses occasionally cause significant problems in vegetable crops. However, the prevalence and severity of viral diseases differ from year to year. Aphids spread many of the viral diseases observed in vegetables. There are two types of viral transmission by aphids, i.e., persistent and non-persistent transmission. It is important to understand the difference between these two because persistent and non-persistent viruses differ both in their uptake and behaviour within the insect vector, consiquently, tactics used to limit their and spread vary considerably. In persistent transmission, the aphid usually carries the virus for life. Uptake of virus requires extended feeding and after an incubation period of several hours or days, the virus replicates and circulates within the insect. Because of the time required for feeding before acquisition by an insect vector, the spread of persistent virus is favoured by colonizing aphid species that spend time in the crop. Controlling the aphid vectors with insecticides can reduce the spread of persistent plant virus significantly. In contrast, aphids can acquire non-persistent viruses (NPV) within a few seconds after sampling an infected plant. Winged migratory aphids can move quickly from infected plants onto healthy ones, transmitting the virus in the process. Aphids rapidly lose the virus particles from their mouthparts, which are cleaned when they feed on the next available plant and are unable to transmit disease to additional plants. Because of the speed in which aphids acquire and transmit non-persistent viruses, insecticides are not usually effective in controlling their spread. One of the most common viruses found in many vegetable crops is cucumber mosaic virus (CMV). This is transmitted by several aphid species in a non-persistent manner. There are several strains of CMV that can infect over 775 different plant species in 85 families including snap bean, peppers, tomato, lettuce, tobacco and sugar beets. Symptoms vary depending upon the plant species infected but range may be from yellow-green mottling on leaves and fruits to severe stunting of plants. The viral diseases affecting different vegetable crops are being discussed below:

Vegetables being good source of carbohydrates, proteins, minerals, vitamins and dietary fibers constitute important component of human diet. These are the cheapest source of natural protective food and increase the palatability. India is the second largest producer of vegetables next to China. Diseases are inherent component of agro-ecosystem, which must be dealt with continuous and knowledgeable basis. Diseases in the standing crop from the seedling stage until harvest and spoilage caused by microorganisms during transit, storage and marketing are major constraints in increasing production and availability of vegetables. At different stages of vegetable production, disease management requires several approaches, and it is more successful, if it is integrated into crop production system. Since vegetables are mostly grown year after year in the same fields especially near towns and cities, therefore, concerted efforts are required to manage the diseases. More than 300 diseases have been reported to occur on vegetable crops and it is beyond the scope of this chapter to discuss all the diseases. However, brief description of etiology, diagnostic symptoms and management practices being adopted are presented here for the economically important fungal and bacterial diseases of vegetable crops.

Seed viability tests

Only two methods, the Topographical tetrazolium (TZ) test and the embryo excision test were previously accepted by the International Seed Testing Association as official methods for some species of seeds. ISTA has recently accepted the X-ray method as a valid alternative to the cutting test for the detection of empty and insect-damaged seeds. The following tests can be applied depending on the circumstances.

Introduction

Agricultural soils harbour a rich variety of nematode fauna, where they coexist with a myriad of other microorganisms. It has been estimated that one cubic meter soil of highly fertile field may contain as many as 3×10¹⁴ bacterial cells (300 g), 5×10⁸ protozoa (39 g), 1×10⁷ nematodes (12 g) and fungi (400 g), besides other organisms. The nemic fauna comprises of free-living (saprophagous and microbivorous), predatory forms and plant parasites (phytophagous). In addition, certain animal and insect parasitic forms may spend a part of their life cycle in soil. Plant parasitic nematodes (PPNs) exist in poly-specific communities and attack all types of plants- cultivated or wild. They possess a needle-like stylet or spear at their anterior end, which is used to puncture the plant cells and ingest the cell contents. Majority of PPNs dwell in soil and draw their nutrition from plant roots. Only a few forms attack the above ground plant parts such as stem, leaves, inflorescence and seeds. PPNs may be ectoparasites (feed from outside and do not enter plant tissues) or endoparasites (enter inside the plant tissues). The endoparasites spend a part of their life cycle in soil or may come out into the soil to re-infect the other roots. These may be further categorized into migratory or sedentary types. The migratory forms keep on moving, feeding and laying eggs that are scattered in soil or plant tissues. The sedentary nematodes are more harmful and a particular stage of their life cycle infects the plant and establishes a feeding site by modifying plant tissues by their enzymatic secretions. The females of sedentary nematodes usually attain swollen shapes upon maturity and lay hundreds of eggs in clusters.

Plant parasitic nematodes are ubiquitous, and so far, more than 1800 species have been recorded. They are obligate parasites and must feed upon plant hosts, thus, debilitating the plants to some extent. The extent of direct damage by the nematodes to plants depends on several factors viz., nematode density in soil, nature of parasitism (ectoparasite or endoparasite), host susceptibility, cropping pattern, edaphic factors (mainly soil texture and moisture) and ambient climatic conditions (like temperature and relative humidity). Nematodes, by themselves, rarely kill the plants to ensure their own survival. Nematodes also inflict considerable indirect damage to crops by interacting with other plant pathogens (fungi, bacteria and viruses) to cause disease complexes in which nematodes act as incitants, aggravators, or vectors.

India is contributing about 10% of the world’s vegetables, and in terms of production, the country stands second after China. The existing area under vegetable cultivation in India is around 6.89 million hectare with a production of about 96.54 million tonnes. There will be a demand of 151-193 million tonnes of vegetables in India by 2030 (Dhaliwal et al., 2006). There are extensive crop losses in vegetable crops due to increased insect infestations. Since vegetables are grown round the year, there is carry over of insect-pests across the seasons and also from sowing until harvesting. Vegetables also invite more pest problems because of their cultivation under high fertility conditions leading to high plant succulence. High yielding varieties and hybrids are further more prone to the attack of insect-pests. Insect infestation affects the quality and market value of vegetables adversely and it is estimated that 30-40% of the total production is lost due to the attack of pests (Lal et al., 2004). A large number of pesticides are being used repeatedly to manage the insect-pests in India. Indiscriminate use of pesticides has led to many problems like toxic residues in edible parts of the vegetables, adverse effects on non-target organisms and beneficial insects, resurgence of secondary pests and development of resistance in major pests to pesticides and also environmental pollution. Therefore, latest approach has been to minimize the use of highly toxic insecticides by integrating different strategies of pest control like use of biological control agents, pesticides of plant origin, insect resistant varieties and other cultural practices. In this chapter, efforts have been made to highlight the distribution, host range, identifying characters, biology and nature of damage of important insect-pests of vegetables and also the methods of their management crop or pest wise.

Seed germination

It is defined as the emergence and development from the seed embryo, of those essential structures, for the kind of seed in question, indicates its ability to produce a normal plant under favourable conditions. The seedlings devoid of an essential structure; showing weak or unbalanced development; decay or damage affecting the normal development of seedling are not considered in calculating the germination percentage.

Concern for improvement of nutritional quality of vegetables has arisen in the context of providing nutritional security to our ever-increasing population. Nutritional security denotes the consumption and physiological use of adequate quantities of safe and nutritious food by every member of the family and encompasses the process of equitable distribution among members of household and communities (Nandi and Bhattacharjee, 2002). This would entail the need to ensure a varied food intake, comprising all the essential macro-and micronutrients (protein, carbohydrates, minerals and vitamins), plant pigments (lycopene, beta-carotene, anthocianin, lutein, capsanthin, zeaxanthin, etc.) and other functional phytochemicals (secondary metabolites, like flavonoids, isothiocyanates, glucosinolates, etc.) through a diversified diet. In this regard, production and consumption of vegetables that are the valuable source of micronutrients, beneficial phytonutrients and highly functional phytochemicals hold the key in assuring nutritional security.

Implication of vegetables in diet has been well conceived among the high-income group in the world since human health in recent years has assumed an unprecedently important status. Increased interests in nutrition, fitness and beauty have exaggerated concerns over diet and human health. A new diet-health paradigm is evolving which places more emphasis on the positive aspects of diet. Foods have now assumed the status of functional foods, which should be capable of providing additional physiological benefits, such as preventing or delaying the onset of chronic diseases as well as meeting basic nutritional requirements so with high-income elasticity, the demand for vegetables and perception of diversified diet have been growing steadily, hence, both access and consumption of vegetables have been increasing in the urban and peri-urban population groups. However, meeting the requirements for macro- and micronutrients for most of the population groups in households and communities of South Asia, Latin America and African countries seems far off because of meager presence of vegetables in the diet. In south Asia where meat intake is low, ascorbic acid emerges as one of the most important enhancers of iron absorption. This is attributed to the fact that foods containing vegetables may provide an optimal mix of minerals, vitamins, antioxidants, dietary fibers and other non-nutrients bioactive compounds.

Diseases of plants are produced by a variety of organisms from plant and animal kingdoms viz., fungi, bacteria, viruses, nematodes and insects. The diseases reduce total biomass (dry matter) production and consequently yield of the crop by general stunting, damage to the leaf tissues, fruits and seeds or by killing the plants. The degree of damage would depend upon the intensity of infection but both need not be proportional. One serious effect of disease is the disappearance from cultivation of otherwise excellent but susceptible varieties.

Vegetable crops have been found to be highly susceptible to biotic stresses from the disease causing microorganisms and insects-pests. The ability of pathogen and insect-pests to attack and proliferate in the host plant is highly specific. There are wide differences in the host plants in response to the attack by pathogens and insects. Although control of the diseases and insects by the use of chemicals is possible to certain extent but indiscriminate use of fungicides or insecticides over the crop has several disadvantages. Besides increasing cost involved in chemical control, residual toxicity of the chemicals such as fungicides, antibiotics and insecticides in food chain and development of resistance against pathogens and insect-pests to different chemicals are serious problems.

Genetic improvement of host plants conferring resistance to diseases and insect-pests is considered to be the best approach in the management of diseases and insect-pests, and this is more particularly true in case of vegetable crops. Indiscriminate use of chemicals in the vegetable sector has led to health hazard. This has resulted in switching towards organic vegetables. However, cost of production of organic vegetables naturally will not permit the common people to consume these products. Therefore, the best option is to induce resistance in the host varieties. The resistant varieties could in turn be an important component in the organic vegetable farming, thereby reducing cost of production to certain extent.

Purity analysis

Purity of a seed lot indicates in percentage how large a fraction is made up of pure seeds of the species in question, and how much is made up of inert matter and other seeds. Impurities may be any non seed material (leaf, flower, fruit fractions, soil etc.), small fractions of seeds of the actual species, as well as seeds of other species. Pure seed may include both dead and empty seed, plus damaged seed, purity does not tell anything about viability. The purity analysis of a seed sample in the seed testing laboratory refers to the determination of the different components of the purity viz., pure seeds, other crop seeds, weed seeds and inert matter. Each component is reported as a percentage of total weight. The objective of the purity analysis is to determine whether the submitted sample conforms to the prescribed physical quality standards with regard to physical components. Large seeds are generally easy to clean and purity analyses are therefore often omitted. However, for smaller seeds contamination with other seeds may occur e.g., during processing.

Hybrid vigour is used as a synonymous of heterosis. In 1910, the term heterosis was first used by Shull who defined this phenomenon as the stimulus of heterozygous, and in his word, it has been the “interpretation of increased vigour, size, fruitfulness, speed of development, resistance to insect-pests and diseases or to the climatic rigors of any kind manifested by the out breeding organism as compared with corresponding inbreds as a specific result of the unlikeliness in the constitution of uniting parental gametes”. This definition is often interpreted as not implying a genetic basis for heterosis, because the definition basically describes the phenotypes that result from the crossing of two different inbred lines. Generally, heterosis is manifested as an increase in vigour, size, growth rate, yield, or some other characteristics but in some cases, the hybrid may be inferior to the weaker parent. This also represents as heterosis (average heterosis), and if heterosis is estimated over the superior parent, such an estimate is sometimes referred to as heterobeltiosis, hence, authors feel “heterosis refers a biological phenomenon in which the F₁ population obtained by crossing of the two genetically dissimilar gametes or individual shows increased or decreased vigour over better parent or over the mid-parental value. Earlier, Power (1944)also suggested that the term heterosis should be used only when the hybrid is either superior or inferior to both the parents. Other situation should be regarded as partial or complete dominance. It can be easily explained with the help of Table 5.1.

Vegetables have always been looked upon as an essential part of diet and are necessary for human health and well-being. Vegetables supply many kinds of nutrients, e.g., carbohydrates, proteins, minerals, vitamins, fibers, phytochemicals, etc. and also add flavour, colour and crispness to foodstuffs. For developing modern day vegetables, breeders have utilized an understanding of genetic principles and applied them for the improvement of these crops. They often make crosses (hybridization) between a crop plant and a related or wild species (a wide cross) enabling valuable genes to be used for genetic improvement of the crops. Over the last few decades, molecular breeding is supplementing plant breeder’s efforts for accelerated genetic enhancement bringing about a revolution in this area. This approach demands efficient procedures for the routine introduction of foreign DNA into plant genomes and utilizing them for the production of novel types of vegetable. In this chapter, attempts have been made to review most of the available molecular breeding techniques, which can routinely be employed in various aspects of vegetable improvement.

Cultivars are developed by selecting for desired traits or by removing undesirable traits that are controlled by genes (the blueprint for all characteristics in living organisms) from existing varieties or breeding lines. The plant species, varieties and clones are identified or selected by their physical features since olden times. However, these traits would change with respect to environmental and climatic conditions. The biochemical parameters like enzymes, proteins, alkaloids, etc. are also likely to change due to the stages of development of plant tissue. Successful selection strategies are dependent on the breeder’s ability to distinguish genetic effects from environmental effects on a visible or measurable trait. Therefore, the scientists resorted to use ‘genetic marker’, i.e., any stable and inheritable variation that can be measured or detected by a suitable method and can be used subsequently to detect the presence of a specific genotype or phenotype, which otherwise is very difficult to detect. Presently, the breeders and scientists all over the world are pursuing mostly DNA or molecular markers.

Vegetables are cheaper source of carbohydrates, proteins, minerals, vitamins and dietary fibers, and hence, assume a place of very great importance in the diet of individuals. All kinds of vegetable are grown almost universally. India occupies the prime position in the production of vegetable crops and is the second largest producer of vegetables in the world. The area and production of vegetables in India have been increasing during the post-green revolution period, and the country is heading towards another revolution in the form of Golden Revolution. However, there is an utmost requirement for genetic improvement of vegetable crops in terms of productivity, qualitative characters and resistance to biotic and abiotic stresses. For any genetic improvement programme, the presence of genetic variation is pre-requisite and mutation is the ultimate source of this heritable variation.

Mutation technique that holds promise of generating a much wider desirable variability than classical breeding has been refined. Out of 2275 mutant varieties worldwide in all crops, as many as 66 mutants are in vegetables. In terms of percentage, China, India, USSR, The Netherlands, The United States of America and Japan account for 26.8, 11.5, 9.3, 7.8, 5.7 and 5.3%, respectively of mutagen varieties in all crops. Such varieties are 3% in case of vegetables. After mutation treatment by a mutagen to a specific plant, DNA alterations (deletion, duplication, inversion, translocation, or transposition of larger DNA fragments, or simple basic pair changes) occur and lead to the DNA sequence change. Hence, new characteristics of that plant are established. In fact, induced mutations supply us with many new plant lines, which may be used as primary materials for crop breeding. Hence, mutation breeding seems to be an effective and ultimate option to improve vegetable crops in the shortest possible time. A large number of new promising varieties in different crops, including vegetables, have successfully been developed worldwide using various mutagens (Chopra, 2005).

Seed sampling

Seed sampling is to draw a portion of seed from seed lot that represents the entire seed lot. Seed lot is a uniformly blended quantity of seed either in bag or in bulk.