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· Seed is the basic and critical input in crop husbandry, which determines the expected dividends from all other inputs.
· It is primarily responsible for maintaining the physical, physiological and genetic characteristics of any variety / hybrid of any crop.
Role of seed
Introduction and popularization of any technology to enhance the crop productivity solely depend on seed. It may be the development of new varieties, evaluation of seed treating chemical, fertilizer, pesticide including the biotechnological developments.
A basic tool for secured food supply
In India for instance, the cultivation of high yielding varieties have helped to increase food production from 52 million tonnes to more than 200 million tonnes over a period of 50 years The successful implementation of the High Yielding Varieties Program (HYVP) in India has led to a remarkable increase in production and to a new assessment of future development potential. As a result, food imports from other countries have been substantially brought down in spite of the rapid population increase.
The principal means to secure crop yields in less favorable production areas
In areas inherent with biotic and abiotic stresses, the supply of good quality seeds of improved varieties contributes to secure higher crop yields.
A medium for rapid rehabilitation of agriculture in cases of natural disaster
At times, floods and droughts focused on threats of famine and starvation. In such situations Seed Reserve Stocks contribute a lot to reclaim the ill effects of natural calamities.
Definition-Quality seed
The capacity of the seeds is fully exerted only when it possess its own quality in terms of physical,physiological, genetic and health aspects. Seed quality is a relative term and means the degree of excellence when compared to an acceptable standard. The seeds having required standards of purity, germination and other attributes are referred as quality seeds.
Characteristics of quality seed
Genetic purity
· Genetic purity of seeds refers to the trueness to type.
· If the seed possesses all the genetic qualities that breeder has placed in the variety, it is said to be genetically pure.
· It has direct effect on ultimate yields. If there is any deterioration in the genetic make up of the variety during seed multiplication and distribution cycle, there would definitely be proportionate decrease in its performance.
· It is, therefore, necessary to ensure genetic purity during production cycles.
Physical purity
· Physical purity of a seed lot refers to the physical composition of seed lots.
· A seed lot is composed of pure seeds, inert matter, weed seeds and other crop seeds.
· Higher the content of pure seed the better would be the seed quality.
· Pure seed considered together with seed germination determine the planting value of the seed.
Seed health
The health of seed refers to the presence or absence of disease organisms/insect pests on seeds. The quality of a seed lot very much depends on its health.
In addition it also should possess the following characters
· It should have good shape, size, colour, etc., according to specifications of variety
· It should be free from other crop seeds,
· It should be free from objectionable weed seeds.
· It should be free from designated diseases
· It should posses high longevity and shelf life
· It should have optimum moisture content for storage
· It should have high market value
The availability of quality seeds in time and at affordable price is a prime factor to produce uniform, healthy and vigorous crop that results in higher productivity. In horticulture, quality seed has got the following significance .
Significance of seed selection
· Ensures genetic purity of specific crop.
· Quality seeds alone ensures higher yield .
· Higher income to farmers
· Produce vigorous seedlings in nursery
· Tolerant to pest and disease to certain extent
· Maintains desired plant population
· Responds to added inputs like fertilizer, pesticide, irrigation and other crop management techniques
· Ensures uniform growth and maturity
· Withstands biotic and abiotic stresses