eChapters

Weight loss: For grains or grain legumes in the tropics, a weight loss in the range of 10-30 per cent might be expected over a full storage season.

Loss in quality/market value: Infested seed is contaminated with insect debris and has increased dust content. Seeds are holed and often discoloured, which fetch low price.

Promotion of mould development: In humid conditions, without adequate ventilation, mould development and caking can spread rapidly, causing severe losses.

Reduced germination in seed material: Damage to the embryo of the seed will usually prevent germination. Some storage pests prefer to attack the embryo.

Concept: The preservation of viable seeds from the moment of collecting until they are needed for sowing is known as storage. Every year, a significant quantity of seeds loses their usefulness due to incorrect storage. Seeds need to be preserved and stored dry. As was previously mentioned, seed moisture content and storage temperature have the biggest effects on how long seeds last. The three main environmental elements that impact seed deterioration and loss of viability are moisture, temperature, and oxygen percentage. For over 90% of species, reducing seed moisture content (MC) to certain thresholds consistently lengthens the seed’s lifespan (Roberts 1973). These species are categorized as “orthodox” in terms of the conditions in which they should store seeds; under suitable dry, cool conditions, they typically maintain viability and germinability even after extended periods of storage. Ellis and Roberts’ improved viability equations have addressed the quantitative impacts of both drying and cooling for orthodox seeds. The life of the seed is often doubled for every 1% drop in seed moisture (when seed MC fluctuates between 5 and 14%) and every 5 oC drop in storage temperature (between 0 oC and 50 oC) (Harrington 1972). Low seed MC and low temperature are hence fundamentals of traditional seed storage. Careful regulation of these two factors is necessary to achieve optimal storage life. But most seed produced annually just has to be kept from harvest until the following planting season. Depending on the type of seed, it may or may not need to be stored at temperatures and relative humidity above room temperature. Regardless of any modifications made for unique uses, the local climate storage facility needs to have a few essential components (Barre, 1954; Wheeler and Hill, 1957).

The purpose of seed storage is to preserve planting seed from one season  to the next. Further, the objective of seed storage is to maintain seed quality for the longest duration possible. 

Relative Humidity and Temperature Influence Seed Storability

The two most important factors that influence the storability of seed are relative humidity and temperature. The effects of relative humidity and its subsequent effect on seed moisture and the temperature of the storage environment are highly inter- dependent. Harrington (1963) gave two useful thumb rules for relative humidity and temperature in reference to storage life of the seed. These rules are as follows :

Seed storage is the preservation of viable seeds from the time of collection to the required for sowing. It is important to get adequate plant stands in addition to healthy and vigourous plants.

Objectives

i. To maintain initial seed quality during storage period by providing suitable conditions.

ii. To maintain the seed germination and emergence rates.

iii. To prevent the seed deterioration during storage period.

iv. To maintain the physical and physiological seed qualities.

Seed Storage is an essential process during seed production programme. The purpose of seed storage is to preserve planting stocks from one season to next planting season.Seed storage starts from the moment of maturity and extend until its planting, in the next season.
 
PRINCIPLES OF STORAGE

Primary aim of storage is simply to prevent deterioration of quality seed. The management objective during the storage period is to reduce metabolic activity to such a low level that the seed is sufficiently stable with minimal deterioration. The two alternative methods are

1.    Reduction of moisture content to a safe level and cooling of the seed.
2.    Modification of atmospheric condition of the storage system.

Types of storage

There are four types

1.    Storage of commercial,  truthfully labelled and certified seed.

2.    Storage of carry-over seeds.

3.    Storage of foundation seed stocks and enforcement seed samples.

4.    Storage for germplasm seeds.

I. FILL UPS

1. _____ is the maintenance of high seed germination and vigour from harvest until planting.
2. _____ is important to get adequate plant stand in addition to healthy and vigours plants.
3. _____ seeds can be dried to 6-10% moisture depending upon the species.
4. _____ seeds cannot be dried below 30-35% moisture and should be maintained at this temperature.

Seeds are having a ability to survive and start a new generation when favourable conditions exists. However like other form of life, they cannot retain their viability indefinitely and eventually deteriorate and die. To retain viability and germination it is important to store in proper storage. Seeds harvested may not be useful for packaging thus making it to store for a period till the need for packaging arises. Seed storage is very critical task of seed processing. The success of seed processing is determined by safe storage. Since the vegetable seeds are expensive need modern techniques of storage. Based on the seed shelf life or longevity vegetable seeds can be divided into two types:

Orthodox Seeds : Orthodox seeds are long-lived seeds. They can be successfully dried to moisture contents as low as 5% without injury and are able to tolerate freezing temperatures. Most orthodox seeds come from annual temperate species adapted to open fields. At physiological maturity they contain moisture content of 30 – 50%. Most of the vegetable seeds are orthodox and hence there is lot of scope for proper storage. E.g-Tomato (6.0 %) and Peppers (7.0%

Recalcitrant Seeds : They are short - lived seeds, which cannot be dried to moisture contents below 30% without injury and are unable to tolerate freezing. They are difficult to ore successfully because of their high moisture content encourages microbial contamination and results in more rapid seed deterioration. Storage of these seeds at subzero temperatures causes the formation of ice crystals, which disrupts cell membranes and causes freezing injury. These seeds are from perennial trees in the mois t tropics such as coconut, coffee, cacao, citrus etc. These seeds mature and exists in their fruits and are covered with fleshy or juicy ariloid layers and impermeable testa. At physiological maturity they contain more moisture content (50- 70%) than orthodox seeds, even though their embryos are only about 15 % of the size of an orthodox seed embryo. In general recalcitrant seeds never go into dormancy but instead continue their development and progress towards germination.

1. SEED STORAGE

Is the maintenance of high seed germination and vigour from harvest until planting.

1.1. Importance of seed storage

Seed storage is important to get adequate plant stands in addition to healthy and vigorous plants.

Seed

A true seed is defined as a fertilized mature ovule consisting of embryo, stored material and protective coats. The seed strictly speaking is an embryo a living organism embedded in the supporting or the food storage tissue.

A seed stands for any of the following used for sowing or planting.

1.    Seeds of food crops including edible oil seeds and seeds of fruit and vegetables.
2.    Cotton seeds
3.    Seeds of cattle fodder
4.    Jute seeds
5.    Seedlings, tubers, bulbs, rhizomes, roots, cuttings, all type of grafts and other vegetative propagated material for food crops or cattle fodder.

Supply chain management or inventory management is an important and integral component of commercial breeding activities practiced by the private seed companies whose over all research efforts in terms of developing and commercially releasing high performing cultivars and hybrids get defeated unless the product reaches to the end users that is the farmers. Seed supply chain management is the lifeline of any seed business especially when the seed business is under private sector seed companies whose delivery is very strong. Supply chain management refers to the process of ordering, storing, and using a company’s inventory. These include the management of raw materials, components, and finished products, as well as warehousing and processing such items and ultimately delivering virtually to the door steps of the farmers through a strong network of dealers/distributors/retailers. For companies with complex supply chains and manufacturing processes, balancing the risks of inventory gluts and shortages is especially difficult and challenging.

The process of supply chain management is a continuously evolving process, ready to deal with the unforeseen situations like the situation created by COVID-19 pandemic forcing countries after countries going for lockdown and bringing the entire business operations including material and men transport to a grinding halt. However, even under these extremely challenging situations, governments fully know that agricultural activities cannot be fully stopped to avoid resurgence of hunger and malnutrition. However, despite the window allowed by the government for running the supply of essential goods including agricultural inputs like seed, agrochemicals and farm machines, manufacturing the agro-inputs including seeds and their distribution to the endpoints has become extremely difficult. A few companies have devised new processes to run seed supply using completely new and innovative approaches, for example, In Bayer’s first-ever e-commerce collaboration in India, the company has tied up with Agro-Star, a Pune-based e-commerce firm in the agricultural segment. Under the partnership, farmers can order Bayer’s seeds and crop protection products for their entire crop lifecycle and receive agronomic advisory through Agro-Stars digital agri-tech platform. Home delivery of agri-inputs can currently be availed by farmers in North, West and Central India, with plans to extend the scope to other geographies in the future. In the current COVID-19 lockdown situation, the partnership has enabled last mile delivery of products for multiple crops directly to farmer’s doorsteps.

Role of Seed Technology

1. Improved seed - a carrier of new technologies

The introduction of quality seeds of new varieties wisely combined with other inputs significantly increase yield levels. In India, the cultivation of high yielding varieties have helped to increase food production from 52 million tonnes to nearly 180 million tonnes over a period of 40 years.

2. Improved seed - a basic tool for secured food supply

The successful implementation of the high yielding varieties programme in India has led to a remarkable increase in production and food imports from other counters have been brought down inspite of rapid increase in population.

3. Improved seed-the principal means to secure crop yields in less favourable areas of production

The supply of god quality seeds of improved varieties suitable to these areas is one of the important contributions to secure higher crop yields.

1. Genetic principles of seed production were given by

   a) Feistritzer (1975)

   b) Kadam (1942)

   c) Kadam (1936)

   d) Swaminathan (1970)

2. Objectionable weed seed in wheat seed production is

   a) Chandvel

   b) Johnsoon grass

   c) Sudan grass

   d) Wild rice

1. Nucleus seed: It is the handful of original seed obtained from selected individual plants of a particular variety. It has the highest genetic purity and physical purity.

Seed Testing
1.    Sampling

2.    Determination of Heterogeneity

3.    Purity analysis

4.    Germination Test

5.    Seedling Evaluation

6.    Quick Test for Viability

7.    Estimation of Seed Moisture

8.    Grow Out Test

9.    Seed Health Test

Seed testing

No matter how good processed seed may look, the actual value is the number of seedlings it will produce. Testing of seeds is therefore imperative to determine and identify the changes that have occurred from the time of collection until the seeds are sold or sown at one time. The critical step in evaluating a seed lot is the drawing of representative sample. Place all the test samples in a bucket, mix them thoroughly and subdivide to obtain sample size. Improvements in seed processing can only be obtained with quality control. These evaluations should be made in the processing plant and at a seed testing laboratory. The National Tree Seed Laboratories offers a free service to evaluate processing machinery. You need only collect a small sample of seed after it has been processed by each machine and send it to the laboratory. Be sure all the seed comes from the same lot so all samples are related. Each machine must be adjusted for efficient operation, and proper adjustment requires monitoring of the operation.

Objective: To study the seed treatment methods and equipments A key factor in achieving the few potential of good quality seed is the blanket treatment of the seeds with agrochemical in order to control or prevent diseases in the  crops.

Objectives

1. To know about the seed treatment of spices and condiments.
2. To know the sowing method and time of spices and condiments.

Seed treatments or seed dressing: Seed treatment refers to the application of fungicide, insecticide, or a combination of both, to seeds so as to disinfect and disinfect them from seed-borne or soil-borne pathogenic organisms and storage insects. It also refers to the subjecting of seeds to solar energy exposure, immersion in conditioned water, etc. The seed treatment is done to achieve the following benefits.

Advantages of seed treatment

1. Protects germinating seeds and seedlings against soil and seed borne pathogens/insects.
2. Seed germination enhancement.
3. Early and uniform establishment and growth
4. Enhances nodulation in legume crop.
5. Better than soil and foliar application.
6. Uniform crop stand, even in adverse conditions (less/high moisture)

Seed is the basic input of agriculture, and its importance has now well recognized in the food supply chain since the warranty for production could be succeeded only based on the availability of seed. Seed becomes the quality seed, on possession of specific characters, viz. germination, vigour, purity and health status, hence, seed production becomes the specified scientific technology with the foreseeing of quality and storability in addition to productivity. From time immemorial, seeds are being imposed with some management techniques for improvement in seed quality and thereby the productivity. These seed management techniques are known as seed treatments. Generally, seed treatment is the application of biological, chemical agents and physical techniques to the seed in order to obtain the benefit of plant protection, production and invigouration. Basically, seed treatments are intended to improve the quality of seeds since nothing can substitute poor quality seed, no matter how lavishly other inputs are spent on the crop established from such seeds. Even for a resource poor farmer, high quality seed would be a great advantage because it ensures the best utility of all inputs in addition to the augmentation of yield increase by 15 to 20%.

In general, seed treatment could broadly be classified into physical and physiological treatment. Physical treatment is external seed treatment, while physiological is impregnation of needy substances into the seed through various seed management techniques. Some of the germination augmenting physiological seed treatments are seed fortification, seed hardening, seed priming, dry permeation and pre-germination. In addition, some of the seeds are imposed with special treatments such as dormancy breaking treatment such as soaking in water, mechanical scarification, acid scarification, bio-scarification, scorching, warm stratification, cold stratification and electrical seed treatment. The common physical seed treatments are seed pelleting, seed coating/film coating and seed colouring. Seeds are also imposed with some other physical treatments that can act on the physiology of the seed such as irradiation, magnetic and electrical seed treatment. In addition, irrespective of seed, seeds are given with protective treatment when they are taken for storage, which are commonly termed as pesticide seed treatment. Seeds are also given with corrective treatment at their initiation reduction with seed quality characters during storage, which are termed as mid storage correction.

I. FILL UPS

1. _____ refers to the application of pesticides to seeds before sowing or storage to protect the seeds.
2. The chemical gases as fumes are used to control the pests in seed lots is called as _____.
3. The treatments given to the seeds prior to or during storage to protect the seed are called _____ treatment.

Seed treatment is one of the important activities of the shop floor. The seed should be treated with various insecticides, fungicides and additives to protect it up to establishment. Some timesenhance quality parameters like vigour which is critical for better establishment. Since vegetable seeds are of very high value and low volume, investment on seed treatment will yield better not only for the seed seller but to the grower also. More number of plants in a field brings moreincome per unit area. Hence the farmer or grower who buys seed is ready to bear the cost of seed treatment making it an important aspect of seed processing.

Seed treatment refers to the application of fungicide, insecticide or both to the seeds to disinfect(deep seated) and disinfest (over seed coat) them from seed borne or soil borne pathogenic organisms and storage insects. It also refers treating seed for enhancing quality by subjecting the seed to solar energy exposure or immersion in hot water or dry heat treatment or priming also.

Definition

Seed treatment is the process by which seeds are treated with physical, chemical or biological agents to prevent the infection of seedlings and the subsequent development of the crops.

Advantages of Seed Treatments

Increased seed germination.

Ensures uniform seedling emergence.

Protect seeds or seedling from early season diseases and insect pests improving crop emergence and its growth.

Lower seedling mortality.

Improved plant population and thus higher productivity.

Reduces the cost and the potential environmental impact.

Also reduces the probability of chemical residues in harvested grain.

Relatively easy and cheap to apply compared to broadcast sprays.

1. SEED TREATMENT

It refers to the application of pesticides (fungicides, insecticides or a combination of both) to seeds before sowing and/or storage in order to protect the seeds and young seedlings from soil borne pathogens and/or storage pathogens and insects. Seeds are thoroughly mixed with required quantities of chemicals namely bavistin (carbendezim) @ 2-4 g/kg of seeds.

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.

Seed Viability Test

Germination test for a seed lot is a pre-requisite to know its potential of emergence under field condition. However, this test requires few days to weeks and a month in some cases. Tetrazolium test gives quick information on seed viability or germinability. It makes possible to distinguish red coloured living parts of seeds from the colourless dead ones. Staining of seeds determines  viability.  Completely  stained  seeds  are  viable  while,  partially and comparatively unstained seeds are non-viable. This test is not valid as compared to seed germination test.

I. FILL UPS

1. _____ is the measure of how many seeds are alive and could develop into plants which will reproduce themselves.
2. _____ method is useful for determining viability of forest tree seeds.

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.

I. FILL UPS

1. Rapid and uniform production of healthy seedling and stand establishment under a wide range of field condition is considered as _____.
2. The sum of those properties of seed which determine the potential level of activity and performance of the seed lot is called _____.
3. Vigour index = _____.

1. DEFINITION

Sum of those properties of seed, which determine the potential level of activity and performance of the seed or seed lot during germination and seedling emergence. i.e., rapid and uniform production of healthy seedling and stand establishment under a wide range of field conditions is considered as seed vigour.

In a vigour test, the seed is introduced to a stressful environment unfavorable to seedling development. This environment can be cool, cold or warm, or a combination of either high humidity and high temperatures, or heavy moisture at low temperatures. A vigor test cannot replace a germination test, but rather supplements it with more information about seed quality.

5.1. Seed village

Compact area approach in which the whole village is involved in seed production.

Concept is a win-win model (Deepak Mullick)

INTRODUCTION

High crop productivity depends on quality of seed as without good quality seed even if we apply manure, Plant protection measure and other cultural practices it is not possible to produce good quality seed. So the basic seed used for sowing must be healthy and good in quality. It is different from commercial production as it need proper care, good quality basic seed, timely cultural operations, thinning, roguing, timely application of pesticides and fertilizers and maintenance of seed quality through inspections. 
Seed production requires technical skill to achieve all the above advantages for which the best approaches Compact Area Approach or Seed Village Concept.
It is selection of compact area by organizing the seed farmers in the selected area. The selected area must be fertile and suitable for reproduction of good quality seed such areas can be organized for self and cross pollinated crops (Groundnut, Paddy, Pulses, Sorghum) especially for the varietal seed production. But the variety should be one another for whole of the selected area.

Advantages of Seed Village Concepts

1. Isolation and Roguing

For maintenance of genetic purity of the crop it requires isolation and proper rouging. This can be achieved in the compact area programme, as it will be the mutual benefit to the farmers who are concentrating growing on single variety on compact area.

I. FILL UPS

1. Seed village is also known as _____.
2. ITC with Zeneca stands for _____.
3. ITC Zeneca has recently changed name to _____.
4. CENSAR stands for _____.
5. _____ is a compact area approach in which the whole village involved in seed production.
6. The concept of seed village is a _____.
7. Seed village concept was started in_____.
8. _____ has guided the experiment in wheat.
9. _____ is a milestone in green revolution.
10. CAPART stands for _____.

1. DEFINITION

Seed village definition is to see that the aim right from the start is to make a holistic transformation in the village. Seed village concept is a “Win-Win model”, says Deepak Mullick, one of India’s foremost professionals in agribusiness. It is also known as “Compact area approach”. Seed village area should be suitable for crop or varieties. Seed in compact area, whole village should be involved. The whole farmers in the village cultivate same crop, same variety and follow same cultivation practices.

“The light of unconditional love awakens the dormant seed potential of the soul helping them ripen, blossom and bear fruit, allowing us to bring the unique gifts that are ours to offer in this life”

–John Wehwood

Introduction

In nature and in humans, seeds are vehicles for spreading new life from place to place. In plants, it refers to the unit of dispersal that survives between seed maturation and its establishment as a seedling. A seed, like a fortress, protects and sustains life as they are well-stocked with special food supplies to endure long sieges. There are many things that seeds are, but above all else, they are the means of survival of their species. It is a way of suspending embryonic development and then resuming it years later after the parents have passed away.

Technically, seed is the sexually produced matured ovule consisting of an intact embryo, endosperm and or cotyledon with protective covering (seed coat). A true seed consist of an embryonic plant, a store of food which consists of cotyledons and endosperm and a protective seed coat. Seed can also be considered as any material that is used for planting or regeneration purpose. Rather than seed, propagating materials like healthy seedlings, tuber, bulbs, rhizome, roots, cuttings, setts, slips, all types of grafts and vegetatively propagating materials used for production purpose is also referred to as seed. Thus, seeds are of two types namely sexual or botanical seed and asexual seed. Both can be used for raising the crops thus forms the agricultural seeds.

Based on the moisture content present, seeds are of two types, orthodox seeds and recalcitrant seeds. Orthodox seeds are the botanical seeds which contain moisture content less than 20%. Such seeds do not germinate even if the moisture content is more than 20% unless artificially forced to germinate. Recalcitrant seeds contain moisture content more than 20% and such seeds will not germinate if moisture content is less than 20%. These seeds cannot be stored for long and for long storage, special structures or conditions are required. Mostly perennial plant species produce this type of seeds.

Seeding /Sowing

Seeding is the process of planting seeds in soil to grow crops, plants, or grass. It is a fundamental step in the cultivation of plants and is essential for agricultural production, landscaping, and reforestation. The goal of seeding is to establish and promote the growth of desirable plants, allowing them to germinate, develop, and eventually mature into a full-grown plant, tree, or crop.

The process of seeding typically involves placing seeds at a specific depth in the soil, providing the necessary conditions for germination (such as water, light, and temperature), and ensuring proper spacing between seeds to allow for healthy plant growth. The choice of seeding method and the timing of seeding can vary depending on the type of plant or crop being grown and the specific environmental conditions of the planting area.

Seeding can be done manually by hand; using specialized seeding tools and equipment, or through mechanized methods, such as using tractors and seed drills for larger agricultural operations. The success of seeding is crucial for the establishment of healthy and productive plants, making it a critical step in agriculture and horticulture.

4.1 Seeding equipment

Sowing is an art of placing seeds in the soil to have good germination in the field and thereby gives better productivity. Seeding is one of the most important farm operations after soil preparation because the time of sowing and the way in which it is done decisively influence germination of the seed and growth of the seedling during its early stages. This in turn affects the subsequent time of weeding and inter-culture, harvesting and threshing and finally the yield. Seed needs an adequate supply of moisture, temperature, air and protected environment for good germination.

Crop sowing refers to broadcasting seeds on the surface of soil, placement of seeds in the soil or transplanting seedlings in the soil, under optimum conditions. The primary functions of any planting operation are to establish an optimum plant population and spacing, the ultimate goal being to obtain the maximum net return per unit area. Plant population and spacing requirements are affected by various factors such as the crop type and variety, soil type, soil fertility level, soil moisture and row spacing upon the cost and convenience of operations such as thinning, weed control etc. In order to get better returns, the right amount of seed should be placed at the right time and at a predetermined depth and spacing in the soil. Usually the depth of sowing depends upon the moisture availability and seed emergence capacity. The amount of seeds to be sown varies according to the size of seeds, percentage germination etc.

The seed drills and planters developed and manufactured in advanced countries are designed to meet the requirements of farmers for the different crops and agro-climatic conditions. These machines are capable of operating at high working speed, cover the large area per unit time and provide the desired plant emergence and stand in the fields. The machines are available to handle the seeds of cereals, pulses, oil seeds and other crops widely grown in the developed countries. In developing countries even though these machines can be made available but they are beyond the reach of small farmers. The level of mechanization of sowing and planting is at a very low level.

Seedling:A seedling is a very young plant that grows from a seed. When the moisture, light, and temperature conditions are correct, the seedling’s development begins with seed germination and the formation of three main parts:

1.Radicle - Embryonic root

2.Hypocotyl - Embryonic shoot

3.Cotyledons - Seed leaves.

In vegetables and annual ornamental crops where generally seed size is small they are germinated in nursery beds or in plug trays indoor (greenhouse) or outdoor(field), hardened before transplanting.

Sapling: A sapling is a young tree, say more than 1 year and less than 3 years’ old. In the life cycle of trees, a seedling converts into a sapling as the next stage of development. It is nearly one-meter tall and generally remains to be known as a sampling until its stem reaches 7 centimetre in diameter. The time period of this stage depends upon the particular species of a tree. In vegetable and annual ornamental crops seedlings generally are one month to 40 days old. Older than this, seedlings do not give better yields on transplanting. Very young seedlings exhibit larger mortality on transplanting.

Transplanting: Transplanting or replanting is the technique of moving a plant by uplifting from one location to another. From nursery beds seedlings or saplings are shifted and planted either in the field or greenhouses for commercial growing. Seedlings are uprooted if grown in soil medium. They are transplanted with growing medium. Uprooted seedlings take time to establish at a new place and face transplanting shock- time taken by roots to establish contact with the soil or growing medium.

It is said that “Success of any production system depends on the kind of seed which are sowing”. It is true for the seedlings also beacause healthy seedlings grown in a well managed nursery will decide the yield and consequently the profit.

Definition of Vegetable Nursery

A vegetable nursery is a place or an establishment for raising or handling of young vegetable seedlings until they are ready for more permanent planting.

Why vegetable nursery is needed

Some vegetable crops require special cares during their early growth period. There are some vegetables with very small sized seeds. Seedlings of many seed propagated vegetable crops like, tomato, brinjal, chillies, sweet pepper, cauliflower, cabbage, knolkhol, broccoli, Brussels sprout, kale, endive, chicory, celery, lettuce, parsley, onion, etc. are first raised in the nursery beds before transplanted in the main field. Many seed propagated vegetable crops viz., okra, peas, beans, radish, carrot, beet, turnip and all the cucurbits (e.g. bitter gourd, bottle gourd, pumpkin, cucumber, watermelon, muskmelon, snake gourd, sponge gourd, ridge gourd, etc.) are conventionally grown through direct seeding in the main field. However, many cucurbits, particularly in the early season are also grown in India using the seedlings raised in polythene packets.

The success of mechanized transplanting largely depends on the quality of seedlings used, making seedling raising an essential component of the process. This chapter revolves around the techniques and practices involved in raising seedlings that are optimized for transplanters. Proper seedling raising ensures that the plants are healthy, uniform, and robust, thereby improving the efficiency of the transplanting process and enhancing crop yields. We will explore various methods for preparing seedlings, including the use of specialized nurseries, seedling trays, and appropriate handling techniques to prevent damage. Understanding these techniques is important for achieving optimal performance from transplanters, reducing labor costs, and promoting sustainable agricultural practices. Transplanting is a common method for controlling weeds in wet or puddled fields. It uses less seed than direct seeding but requires significantly more labor. Additionally, transplanted crops tend to take longer to mature due to transplanting shock.
TECHNIQUES OF MANUAL TRANSPLANTING
Manual transplanting can be performed using two different methods:
Random Method
In the random method, seedlings are transplanted without maintaining a set distance or spacing between plants. While it’s difficult to establish equal distances between each hill in this method, it is crucial that the estimated distances are neither too close nor too wide. The spacing should range between 10 cm and 25 cm to ensure effective weed control through early shading from the rice canopies.

Seed is a fertilized ripened ovule consisting of three main parts namely seed coat, endosperm and embryo which in due course gives rise to a new plant. Seed is the nucleus of life. Endosperm is the storage organ for food substance that nourishes the embryo during its development. Seed coat is the outer cover that protects or shields the embryo and endosperm.

Importance

Plants reproduce sexually by seeds and asexually by vegetative parts. Grains which are used for multiplication are called seeds while those used for human or animal consumption are called grains. Good stalks of planting materials are basic to profitable crop production. The seed or planting material largely determines the quality and quantity of the produce. A good seed or stalk of planting material is genetically satisfactory and true to type, fully developed and free from contamination, deformities, diseases and pests.

Seed is the living link between plant and progeny and biologically seed is ripe fertilized ovule and a unit of reproduction of flowering plant. Agronomically, a seed material or propagule is the living organ of crop in rudimentary form used for propogation.

Propagation Asexual Sexual Seed Stem cutting Ex: Sugarcane Grafting Rooted slips Ex: Grasses Tubers Ex: Potato Budding Corms Rhizomes Layering

Plants perpetuate / multiply either sexually or asexually. Sexual methods are through seeds and asexually through vegetative parts. Most of the crop plants produce viable seeds which are used for sowing. Those used for multiplication are called seeds and those which used for human consumption are called grains.

Seed consisting of intact embryo, stored food and seed coat which is viable and has got a capacity to germinate. Embryo has two parts:

A seed consists of a plant embryo, stored food material surrounded by a seed coat. Seeds of cereals and grasses consist of embryo or germ, endosperm and the pericarp.

Seeds of legumes contain no endosperm, the bulk of the seed being made up of the two cotyledons. The cotyledons constitute the food storage portion.

The embryo of the grass seed is made of epicotyl, hypocotyl and scutellum- the single cotyledon of monocots, the epicotyl gives rise to the shoot and the hypocotyl produces the roots.

Part A

Counting of Seeds in a Seed Lot

Counting of seeds is essential in order to estimate the number of seeds required for planting in a nursery or direct sowing or where seeds are valuable and are sold or purchased on number basis. However, in practice, it is difficult to count the seeds in the entire lot. Alternately, the whole lot is weighed accurately. From the whole lot, 5-6 small seed samples of 100 g each are randomly selected. The number of seeds in these samples are counted. The average of these samples is then applied to the whole seed lot in order to calculate the number of seeds.

Seepage is the movement of water through the soil body and foundation of a hydraulic structure. In an earthen dam, uncontrolled seepage may produce excessive water loss, high pore-water pressure, slope instability, internal erosion, piping, or complete structural failure. Seepage analysis therefore determines the quantity and path of water movement and helps engineers design filters, drains, impervious cores, cut-offs, and other protective components. This chapter explains the objectives and importance of seepage analysis, Darcy’s law, permeability, seepage velocity, phreatic lines, flow nets, equipotential lines, and flow channels. It also examines seepage forces, piping conditions, exit gradients, and methods for improving dam safety.