eChapters

I. FILL UPS

1. _____ is the most important primary pests of cereals.
2. _____ causes serious damage in maize cob.
3. _____ is the field pest of pulses.
4. _____ feeds on already damaged.

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 :

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.

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.

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.

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.

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

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.

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

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.