Quality Seed Is The Carrier of New Technology

INTRODUCTION

Plants are propagated either by sexual or asexual methods. Propagation through seeds is the sexual method of plant multiplication. Most crop plants produce viable seeds which is used for sowing and those used for human or animal consumption are called grains.

SEED

• A seed is an embryonic plant enclosed in a protective outer covering called seed coat.

• Seed is the ripened ovule and is the basis for the sustenance of the spermatophytes.

• The study of the seed is called as Spermology.

• A typical seed includes two basic parts: I. an embryo II. a seed coat.

• Embryo is the fertilized ovule or an immature plant from which a new plant will grow under proper conditions.

• In the fruit of grains, the single monocotyledon is shield shaped and hence called as Scutellum.

• The seed coat helps protect the embryo from mechanical injury, predators and drying out.

• Depending on its development, the seed coat is either: i) Unitegmic seed coat: It has only one covering layer. ii) Bitegmic seed coat: It has two coverings- testa (outer) and tegmen (inner)

What is QUALITY SEED??

• If the seed posses high genetic purity and high germination percentage and a minimum of inert, weed and other crop seeds and is free from diseases, it is said to be the quality seed.

• It is estimated that good quality seeds can contribute about 20-25% increase in yield.

Characteristics/Attributes Of Quality Seed:

It must be genetically pure: Breeder/nucleus: 100 % Foundation seeds: 99.5% Certified seeds varieties: 98% Certified hybrid seeds:95%. It should have required level of physical purity: All crops: 98% free form other crop seeds (number/kg),free from objectionable weed seeds ,free from designated diseases ,high germination and vigour , optimum moisture content Cereals: 10-12 % ,Pulses: 7-9% ,Oilseeds:6-7% ,Vegetables: 5-6%.

HOW QUALITY SEED IS THE CARRIER IN NEW TECHNOLOGY?

The advent of modern plant breeding methods and biotechnological advances in seed industry plays a significant role in developing of high yielding varieties and hybrid. The relationship between quality seed and new technology can be discussed in two parts:

I. Technological advancement during the development of quality seed.

II. Technological advancement during exploring the total yield potential of the quality seed sown.

DEVELOPMENT OF QUALITY SEED

• Physical purity of the seed can be obtained by the process of removal of inert matters and other distinguishable varieties (O.D.V.). It can be done by the ODV test technology.

• Genetic purity can be attained by developing true to type varieties. It can be done by preserving the unique and desired characters of the mother seed by avoiding the unnecessary pollination and crossing over. This led to the rise of Bagging and character selection at the genetic level.

•Inoculation of the desired characters to the seed requires the gene transfer. For ex. Transfer of disease resistant gene to the seed.

•For the development of the quality seed, Rhizobium inoculation is done to increase the yield through symbiotic association with the root of the leguminous crops.

•Determination of the moisture content requires the Moisture meter.

•Viability of the seed is known or tested by Tetrazolium Chloride test or Tz test.

•Germination test is carried in the seed laboratories to determine and label the germination percentage.

•Field establishment trials are also done to know the adaptability of the seed.

•Development of the pest resistancy for quality seeds also contributes to the invention of the new technologies.

EXPLORING THE TOTAL YIELD POTENTIAL OF THE QUALITY SEED SOWN.

Seed treatment and incubation are the techniques used to increase the plant population by minimising the germination failure due to moisture stress. High Density Planting (HDP) also depends on the quality seed. This also give rise to the technique of the Crop geometry and spacing. Use of qualitative and improved seeds demands the extensive and balance use of NPK fertilizer. This leads to the investigation upon the techniques of the Integrated Plant Nutrient Management(IPNM). Integrated Weed Management(IWM) is also a tool and technique of realizing optimum yield potential of the seed sown. Proper development of the irrigation system is also one of the technologies developed to explore the optimum yield potential of the seed. Development of the Package of Practices(POP) lead to the realization of the total yield potential.

Writer: Bandana Khanal (Student, Bsc Ag 4th Sem, IAAS, Paklihawa Campus)