Preface “Agriculture is sterile without seed” Seed is a resource instrument of change as the three basic necessities of a human being i.e. food, clothing and shelter are met by agriculture and agriculture revolves around seed. Improvement of ovule to seed and seed to plant ratios were the main aims of all research and developmental efforts of seed science and technology. Being a connecting link between two generations of crops, seed is a carrier of new technology or new improvements made by the breeders. The seed production protocols then need to be efficient enough to produce seeds that possess desired quality traits in terms of genetic, physical, physiological and health quality. Hence, the implementation of improved seed production technology of various crops may improve the ovule to seed ratio in the mother crop and seed to plant ratio in the subsequent crop raised from the seed. Seed Science and Technology is the science of new discipline which deals with the principles and methods of production of quality seed and improving the quality of the seed by various seed enhancement techniques starting from sowing till the storage. The Importance of seed quality can be felt by the proverb “what are known as Seeds of Hope may turn into Seed of Frustration if Quality is not maintained”. The multidisciplinary development of the subject has necessitated an up to-date knowledge of this aspect of science in order to truly comprehensive synthesis of the whole field of seed. The splendid growth of this science has catered to the development of related areas viz., Biology, Biochemistry, Biotechnology, Pathology and Entomology, which has direct and indirect impact on Seed Science and Technology. This book entitled “Seed Technology: Progress and Recent Advances” have been formulated to help the reader in acquiring the knowledge of Seed archaeology, Seed germination, Seed vigour testing, Seed certification and testing of genuineness of varieties through morphological, biochemical and molecular markers, advances in hybrid seed production, advances in plant pathology, advances in entomology, advances in seed enhancement techniques like, seed pelleting, seed coating, seed hardening, synthetic seed, etc. It also includes the area of applied science and covers the area of organic seed production, seed banks, seed legislation and law governing the seed production. The book would be also useful and instructive to students and researchers in the field of Seed Science and Technology in an efficient way. We very much thankful to all the authors who have contributed in the compilation of different chapters in the book. Also tanks to Dr. A. R. Pathak, Hon’ble Vice Chancellor, Junagadh Agricultural University, Junagadh, for their kind moral support in writing this book and for giving valuable suggestions.

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 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).

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

Introduction 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.

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 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.

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 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 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 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 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 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.

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 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

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.

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 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.

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 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).  

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.