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Seed certification

It is a legally sanctioned system for quality control and seed multiplication and production. It involves field inspection, pre and post control tests and seed quality tests. As per Indian Seed Act seed certification is voluntary and it is not compulsory. The seed that is sold in the market is of two types certified seed or truthfully labelled seed. Whereas truthfully labelled seed is one which is being produced and marketed by the producing company by maintaining the labelling standards.

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.

1. SEED CERTIFICATION

Seed Certification is a legally sanctioned system for quality control on seed multiplication and production. It involves field inspection, pre and post control tests and seed quality tests.

1.1. Phases of Seed Certification

Certification shall be completed in six broad phases listed under

The collection of cones/fruits and seeds is the first step in the harvest, processing, and storage of seed in which man interacts with nature in determining ultimate seed quality. Successful collection, therefore, depends on understanding seed maturation and dispersal characteristics of each species, knowing local weather trends, and evaluating crop quality. Collection of propagating material is an expensive process and it is therefore also important that areas wherein cones and seeds are to be collected are evaluated to determine whether a sufficiently heavy crop to permit economic collection of seeds is present and whether the seed zone and elevation represented by the candidate area is appropriate for the production of seedlings needed in the reforestation program. Remember that properly collected, processed, and stored seeds may remain viable for a decade, so evaluation of seed needs may be projected well in advance of current harvest schedules through proper planning and organization of seed collection.

• The seed production of varieties and hybrids should be carried out carefully by following various techniques in the region where they are well adopted.
• The various factors affecting quality seed production includes,
  1. Agro climatic factors / Ecological factors - edaphic and climatic factors
  2. Production factors
  3. Post harvesting handling of seed
  4. Seed quality control factors

I. FILL UPS

1. _____ is defined as deteriorative mechanism occurring with time that increase the seeds vulnerability and decrease ability to survive.
2. Lettuce seeds develop red necrotic lesions in cotyledons known as _____.
3. _____ morphological changes occur in ground nut due to deterioration.

1. DEFINITION

Seed deterioration is defined as deteriorative changes occurring with time that increase the seed’s vulnerability to external challenges and decrease the ability of the seed to survive

The important events involved in seed development and maturation include

• Pollination
• Fertilization
• Development of the fertilized ovule by cell division
• Accumulation of reserve food material
• Loss of moisture content

Seed dormancy

Plants evolve many mechanisms that ensure their survival. For instance, some species produce prodigious number of seeds so that even if only a small proportion germinate and grow, some seedlings will survive. Alternately, dormancy can be defined as: a seed characteristic, the degree of which defines what conditions should be met to make the seed germinate. This definition may be more useful in understanding dormancy because it suggests that dormancy is variable, rather than constant, which is the situation that we generally encounter in the native populations of many species. The staggering of germination (dormancy) is an advantage for seeds that mature in late summer to early fall, since immediate germination would leave vulnerable seedlings exposed to harsh winter conditions.

I. FILL UPS

1. _____ refers to lack of growth due to any external or internal cause.
2. _____ refers to a state in which viable seeds fail to germinate even when given favourable environmental conditions.
3. _____ is a condition in which seed can germinate upon absorption of water.
4. _____ is otherwise known as primary dormancy.
5. A condition that develops to prevent germination after the seed has been detached from the plant is called _____.
6. Dormancy related to the embryo is called _____.

1. INTRODUCTION

In general, seed dormancy refers to lack of growth due to any external or internal cause. It also refers to a state in which viable seeds fail to germinate even when given favourable environmental condition i.e. adequate moisture, appropriate temperature regime, a normal atmosphere and in some cases light.

There are various degrees of dormancy varying from very slight to very strong (deep). Sometimes the development or degree of dormancy changes during the lifetime of the seed, usually as a response to external conditions. Hence, dormancy may be innate, develop, be broken and redevelop in seed.

Several types of dormancy exist, and sometimes more than one type of dormancy occurs in the same seed. In nature, dormancy is broken gradually or by a particular environmental event. The type of event that may break dormancy depends on dormancy type. Dormancy caused by a hard seed coat may be overcome by a gradual or an instant abrasion, and darkness induced dormancy by exposure to light. In seed handling, the natural dormancy breaking mechanism is applied or simulated during the process of pretreatment. “Pretreatment” is a term used for conditions or processes applied to break dormancy prior to germination, while “treatment” is used for application of pesticides for control of pests and diseases.

Drying is an important unit operation in seed processing in order to maintain seed ability and vigor . it is advocated that seeds should be harvested soon after they attain physiological maturity to obtain better quality seeds and to minimize field losses. The traditional method of sun drying is inadequate, uncontrolled and time bound, which may not meet the high demand of quality seeds in time. Hence artificial drying, the effect of certain drying parameters like seed moisture content, drying air temperature, airflow rate, depth of seed loading and time of exposure on drying characteristics and viability of seeds are to be determined for safe and economical drying of seeds.

I. FILL UPS

1. The process of eliminating moisture from the seed is called_____.
2. _____ is the common conventional method, in which drying of harvested crop is carried out in the field.
3. In _____ method the outside air is heated with the help of burner heater and circulated into the godown.

1. SEED DRYING

The process of elimination of moisture from the seed is called drying.

2. STAGE OF MOISTURE ELIMINATION

The moisture from the seed is eliminated in 2 stages

1. Surface moisture of the seed that initially removed by the drying air.
2. The removal of the moisture in the surface cause an imbalance in the moisture potential in the surface of the seed and the inner portion of the seed which leads to the migration of moisture from the inner organ to the surface.

The migration of moisture to the surface is slower than the evaporation and a moisture gradient is developed in the kernel. Elimination of moisture from the seed depends upon the relative humidity and temperature of the environment surrounding the seed.

1.1 Problem
    1.    Compare the seed quality at different physiological maturity stages
    2.    Compare the seed recovery in acid and fermentation method

1.2 Materials
    ·    Tomato fruits – 4 batches
    ·    Plastic bucket/ Beaker
    ·    Water

I. FILL UPS

1. The seed removal in wet fruits is known as _____.
2. The seed removal in dry fruits is known as _____.
3. _____ is used for mechanical extraction.

1. SEED EXTRACTION

The processing of seeds starts from the extraction of seed material from the plant parts. The seed removal in dry fruits is known as threshing, while that of wet fruits is known as extraction.

2. METHODS OF SEED EXTRACTION

2.1. Dry extraction

Dry extraction is done either manually or mechanically. Manual extraction is by beating with pliable bamboo stick or by beating against a hard surface. Threshers are used for mechanical extraction. In this, care should be taken to avoid mechanical injury. Eg. All agricultural crops.

1. OVULE DEVELOPMENT

The development of ovule occurs within the ovary, which provides a location for nurture and development of the female gametophyte, its sexual fusion with in the male gametophyte, and embryo development, survival, and eventual regrowth (Fig. 1). Ovule growth begins as a small outgrowth within the nucellus. As megasporogenesis and megagametogenesis continue, the region of the nucellus that is to become the ovule enlarges and differentiates into definite morphological characteristics. Secondary outgrowths, or collars (integuments), soon appear around the periphery of the nucellar outgrowths and envelop it. These usually consist of the inner and outer integuments and ultimately become the testa (seed coat) of the mature ovule.

Fumigation is a method of pest control that completely fills an area with gaseous pesticides to suffocate or poison the pests within. It is utilized for control of pests in buildings, soil, seed, and grain produce. It is also used during processing of goods to be imported or exported in order to prevent transfer of exotic organisms. Fumigants are chemical compounds in gaseous form that enter the body of insect through the spiracles spread all over via trachea and tracheoles. The important fumigants are Methyl bromide, Ethylene dibromide, Aluminium phosphide, Ethyl formate, Hydrogen cyanide, Chloropicrin etc.

I. FILL UPS

1. _____ is the progeny of nucleus seed.
2. Genetic purity of breeder seed is _____.
3. Physical purity of breeder seed is _____.
4. The colour of tag for breeder seed is _____.
5. _____ is the progeny of breeder seed.
6. Genetic purity of foundation seed is _____.

1. SEED CLASSES

Generation system of seed multiplication is nothing but the production of a particular class of seed from specific class of seed up to certified seed stage. The choice of a proper seed multiplication model is the key to further success of a seed programme, which basically depends upon

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.

I. FILL UPS

1. The process whereby seeds sprout and begin to grow is known as _____.
2. During germination of a seed, the water is absorbed through _____.
3. _____ is the onset growth of a seed often following a period of dormancy.
4. _____ is a type of germination in which cotyledons and shoot are carried above the soil level.
5. _____ is a type of germination in which the cotyledon or comparable structure remain in the soil.
6. Water moves into the tissues and cells by _____.

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.

1. SEED GERMINATION

The process whereby seeds sprout and begin to grow is known as germination.

Germination is the onset growth of a seed, often following a period of dormancy, in response to suitable environmental conditions. During germination (the growth and development process) of a seed, the water is absorbed through micropyle, and the formerly dormant embryo resumes growth and emerges from the seed.

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.

I. FILL UPS

1. _____ refers to the health status of a seed.
2. A group of fungi that infects developing seeds on the plant in the field, but before it is threshed is called as _____.
3. _____ fungi invade seeds at (or) after harvest.
4. _____ method is used particularly for smut and bunt fungi in gramineous host.
5. _____ method is used for detection of karnal bunt of wheat.

1. INTRODUCTION

Seed health refers to the health status of a seed. Sowing healthy seeds of high quality is our concern to improve crop yields, thus increasing food production. It has a great concern to farmers and seed producing agencies where the disease is high and average yields are low and where more food is needed to feed the ever-increasing population. So, it is important to test the seeds for disease organism before they are sown in the field and to avoid harmful organisms traveling from infected to non-infected areas within a country or across international boundaries.

I. FILL UPS

1. RCA stands for _____.
2. Expert standing committee was set up in _____.
3. In _____year, All India Co-ordinated maize improvement programme was started.
4. First maize hybrid was released in the year _____.
5. All India co-ordinated bajra and sorghum improvement programme was started in _____.
6. First sorghum hybrid was released in the year _____.

1. SEED INDUSTRY BEFORE INDEPENDENCE

The Royal Commission on Agriculture (RCA) constituted in 1925 suggested the following for seed improvement

There should be a separate organization within agriculture departments to deal with seed distribution and seed testing.

The seed distribution enterprise should be self-sustaining.

Seed distribution should be organized through co-operatives, other associations, seed merchants (whenever they are available), through seed agents, as well as through agricultural department staff and any other agency which could be considered suitable.

Seed merchants of proven enterprise should be given every encouragement.

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.

The basic aim of seed legislation and its subsequent enforcement is to regulate the quality of seeds sold to farmers. So long as Agriculture remains tradition and static, there is little justification for regulating seed quality. However with technological advancement and the systematic application of science to Agriculture, it becomes compulsory to regulate the quality of seeds through seed legislation and its subsequent enforcement to ensure that seed buyers are not made to run undue risks.

TYPES OF SEED LEGISLATION

Seed legislation can be broadly divided into two groups.

1.    Sanctioning legislation

2.    Control legislation

Sanctioning Legislation

Which authorizes, establishes or otherwise legally sanctions such activities as formation/establishment of advisory bodies, seed certification agencies, seed testing Labouratories, foundation and certified seed programmes, recognition of seed certification agencies of foreign countries, appellate authority etc.

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

I. FILL UPS

1. _____ refers to the actual acquisition and selling packed seeds, intermediate storage delivery and sales promotional activities.
2. _____ entails using marketing information for the purpose of planning.
3. _____ is one of the major channel through which bulk of paddy seeds, pulses seeds and oil seeds are marketed in the state.

1. DEFINITION

Seed marketing is the one of the most vital components of seed technology. On it depends the size and scope of the seed industry. Broadly it includes such activities as production, processing, storage, quality control and marketing of seeds.

Seed marketing refers to the actual acquisition and selling of packed seeds, intermediate storage, delivery and sales promotional activities.

1. SEED MATURITY

Harvesting should be done after the attainment of physiological maturity, when the seeds reached complete maturity to avoid harvesting of immature and ill-filled seeds.

1.1. Physiological maturity

It is the stage of accumulation of maximum drymatter within the seeds. It is expressed by maximum seed weight, germination and vigour potential. The moisture content of the seed at this stage is around 25-30% depending up on the species.

1.2. Harvestable maturity

The physiological maturity is represented to a seed and this maturity will not be the same for all the seeds of a single plant / population, due to continuous differential flowering habit. Hence, the stage of attainment of physiological maturity by 80% of the population is considered as the harvestable maturity stage. The moisture content of the seed will be lesser than the physiological maturity stage (18-20%).

I. FILL UPS

1. _____ is the stage of accumulation of maximum dry matter within the seeds.
2. The stage of attainment of physiological maturity by 80% of population is considered as _____ stage.
3. In rice, during harvestable maturity the moisture content of long duration varieties will be _____.
4. For short and medium duration varieties of rice, the moisture content will be _____.
5. Rattling sound of kernel is the physiological maturity symptom of _____.
6. The harvestable maturity indices of cotton is _____.
7. The harvestable maturity indices of bhendi is _____.

I. FILL UPS

1. _____ is one of the most important deciding factors of seed viability and quality during storage.
2. Indirect method of moisture estimation is_____.
3. Karl fisher titration method is _____ method of moisture estimation
4. For volatile oil containing seeds moisture is estimated by_____.

1. SEED MOISTURE

Seed moisture is one of the most important deciding factors of seed viability and quality during storage. Hence, determination of seed moisture content and drying to the safe moisture content is utmost important before transit and storage.

According to ISTA (1985), moisture content of the sample is defined as that loss of weight when it is dried in accordance with the rules or the amount of water collected when it is distilled. It is expressed as percentage of the original weight of sample (wet basis).

1.1. Principle

Moisture present in the seed is removed completely as much as possible without oxidation or decomposition or loss in other volatile substances by applying heat. The weight loss due to drying is estimated and the moisture content is calculated.

The seed moisture content is the amount of water present in the seed. It is generally expressed in percentage of dry and wet seed weight. It is the loss in weight of the original sample when it is dried. High moisture content in seed sample favors the mechanical damage, seed longevity, incidence of disease and insect pests.

Objective

i. To know the moisture content of seeds by suitable methods
ii. To suggest the seed drying.

Multiplication and distribution of high quality seed of improved varieties is a crucial step in agricultural production of any country.

When an entry is identified by the workshop of the concerned project, the breeder begins the seed multiplication of the strain in the following crop season. The seed produced by the breeder after a strain is identified, but before it is released as a variety is termed as the “stock seed”. This seed is known as breeder seed after it is released and notified. In the crop season following notification foundation seed of newly released variety is produced. In the second crop season following the release of variety, certified seed of the variety is produced. Thus the farmer is able to obtain certified seed of a newly released variety for commercial cultivation only in the third crop season following in the notification of the variety. However the seed of such variety reach the farmer even before its release through mini-kit trials. Many other farmers would obtain the seeds from those farmers who conducted the mini kit trials and so on in the next two years. Thus an outstanding variety is likely to reach many farmers even before its certified seeds have been put on sale.

Abstract

Although  people have harvested seeds and fruit from trees for centuries, only after World War II, the science and theories of forest genetics begin to be seriously applied to and practiced in operational forestry around the world. The genetic improvements, or gains, need to be captured, packaged, and mass produced so that these gains could be deployed in operational forestry systems. This can be accomplished through seed orchards which is a link between tree breeding and silvicultural activities. Seed orchards are by far the most frequently used sexually reproducing forestry production populations in the world. Apart from the genetic improvement, seed orchards are also used for the production of seed that is well adapted to specific environments. Seed orchards can be categorized according to the generation of breeding or the type of plant material used.

Seed Packing

Seed packaging is the process of filling, weighing and sewing of bags with seed. The choice of packaging materials and amount of seeds to be packed depends on kind of seeds to be packed, duration of storage, storage environment, the seed moisture content, the cost of seed, the cost of packaging material, the geographical area where the seeds will be stored.

I. FILL UPS

1. The area of science that studies the relationship between pathogens and seeds is _____.
2. The diseases that are caused by fungal pathogens in residues and on the soil surface are defined as _____.
3. The establishment of a pathogens in any part of the seed is referred as _____.

1. SEED PATHOLOGY

The area of science that studies the relationship between pathogens and seeds is seed pathology.

2. TYPES OF PATHOGEN

Diseases of plants are caused primarily by three types of pathogens: bacteria, fungi, and viruses. Despite that fungi comprise the largest group of pathogens, the bulk of seed-specific diseases are caused by bacteria or viruses. This is due to the fact that bacteria and viruses are more adopt at entering and then travelling through the veins of the plant, a phenomenon known as ‘systemic infection,’ and from the vascular system may make their way into the developing embryos of seeds.

Fungi, in contrast, tend to be restricted to the outer layers of the plant, where they initiate infection by means of air-borne spores and then proceed to spread by attacking nearby cells of the outer layers. Fungi are much less likely to enter the vascular system of the plant, and thus infect seed mostly when they either ‘crawl’ all the way to seed on the outside of the plant, or else send out spores that land on the seed. In either case, the fungal spores are on the outside of the seed, in the layers of the seed coat, spores on the seed coat are more prone to either dry up and die, or else to get sloughed off with the seed coat during seed germination, thereby failing to cause disease on the next generation of plants.

The objective of seed pelleting is to provide an opportunity to package effective quantities of materials such that they can influence the micro-environment of each seed.
 
Process of Pelleting

Seeds are introduced into a coating drum or pan that resembles a cement mixer. An amalgam of pelleting materials (clays, limestone, calcium carbonate, talc, vermiculite) and cementing adhesives (gum Arabic, gelatine, methyl cellulose polyvinyl alchol) are used to form the pellet and other compounds such as inoculants, fungicides, etc. May be added to enhance seed performance.

I. FILL UPS

1. _____ is basically a critical assessment of effective seed requirement.
2. _____ is the ratio of seed yield per seed generation.
3. The quantity of quality seed that have replaced the actual seed requirement of the location is _____.
4. SRR for hybrid seeds is _____
5. Seed multiplication ratio for groundnut _____

1. INTRODUCTION

Indian population is estimated to increase to about 1400 million by 2025. Consequently, India’s requirements for food grains and other food products to feed the increasing population will continue to rise. The food grain requirements are estimated at 350 to 370 million tonnes by 2025. The demand pattern for agricultural commodities for the domestic market will also shift as a result of increasing incomes and faster urbanization. Compared to 26% increase in 1991, the urban population is projected to increase by 42% in 2020. For competing in the global market, the product pattern will shift to high value commodities like fruits, vegetables, floriculture, dairy products, meat and marine products. In such a future scenario, it is necessary to increase agricultural production through improved cropping system, judicious use of agro-inputs and wide use of modern agricultural technology. It is also important to augment and streamline the existing marketing system including handling, transportation, storage, processing and distribution.

I. FILL UPS

1. The Seeds Act was passed in the year _____
2. Seed Control Order was passed in the year _____
3. The New Policy on Seed Development was passed in the year _____
4. Seed Act came into force in _____
5. In _____ year, Seed Rules were formed.
6. In _____ year, Seed Certification Agencies and Central Seed Certification Board were formed.

1. INTRODUCTION

Seed is the most important determinant of agricultural production potential, on which the efficacy of other agriculture inputs is dependent. Seeds of appropriate characteristics are required to meet the demand of diverse agro-climatic conditions and intensive cropping systems. Sustained increase in agriculture production and productivity is dependent, to a large extent, on development of new and improved varieties of crops and an efficient system for timely supply of quality seeds to farmers..