Monday, 1 April 2013

Agriculture notes prepared by IAS Topper for all agriculture based competitive exams-Seed Technology


Seed Technology

It comprises techniques of seed production, processing, seed storage, seed testing and certification, marketing, distribution and related research on these aspects. The role of seed technology is as follows

Seed - as a carrier of new technology
Seed - basic tool for secured food supply (green revolution by high yielding varieties)
Seed - Principle mean to secure crop yield in less favourable areas of production (by modifying variety suitable to the condition)
Seed - Medium for rapid rehabilitation of Agriculture in case of natural disaster
Goals of Seed technology
·         Rapid multiplication
·         Timely supply
·         Assured high quality of seeds
·         Reasonable price

Importance of Seed Technology

Seed technology involves development of improved crop varieties, their evaluation and release, seed production, seed processing, seed storage, seed testing, seed certification, seed quality control, seed marketing and distribution.
·         Research would be of little use if a farmer doesn’t get seeds which are genetically pure and possess other desirable qualities namely germination percentage, vigor, purity and health of seeds etc.
·         Among the inputs used by the farmer, seed is the cheapest. Without good seeds, the investment on fertilizer, water, pesticides and other inputs will not pay the required dividends.
·         The pace of progress in food production will largely depend upon the speed with which the seeds are multiplied and marketed with good quality and high yielding potential
·         Seed is the easiest input for crop improvement in a shorter period of time. Also it is the easiest one to be adopted by the farmers.

How to maintain genetic purity?

·         Use of approved class of seeds Ex. Certified seeds
·         Isolation Distance: To avoid contamination which can occur natural crossing with offtypes and nearby field varieties, mechanical mixtures during different harvest operations and seed borne disease from nearby fields
·         Roguing of Seed field: To avoid offtypes (plants different from that of seed variety). Offtypes arise through recessive genes expressed during segregation, mutation, volunteer plants and mechanical mixtures
·         Seed Certification: Principle aim of seed certification is to maintain good seeding value and true to variety. Seed certifying agency inspect at various levels of seed production to inspect for field standards, isolation distance and other related parameters, inspection of seed lot and conduction of quality test and draw of samples from processed seed lot to maintain desired standards.
·         Grow out test – to test the genetic purity of the samples

Seed Standards

Field Standards

  1. Isolation distance – between two similar fields, to avoid contamination of pollens from two different sources
  2. Number of field inspections – to take care of all other unwanted to mix with desired seed production
  3. Off types – to remove pollen shedders, off types, shedding tassel etc.
  4. Objectionable weeds – To remove notorious weeds which are perennial and cause severe loss by way of yield reduction and harbouring pest and diseases
  5. Inseparable other crop plant – to remove those crop seeds which look similar to parent seed lot
  6. Plant heads affected by disease

Seed standards

  1. Genetic purity of seeds
  2. Germination percentage
  3. Inert matter
  4. Other crop seeds
  5. Weed seeds
  6. Objectionable weeds
  7. Diseased seeds
  8. Other undistinguishable variety seeds

Seed Inspections

- It is done by the seed certification agency in order to ensure the field and seed standards
- Time of Inspections are planned and fixed before, normally it is at

Field inspections

  • Time of sowing
  • Pre-flowering stage
  • Flowering stage
  • Post flowering stage
  • Harvest stage

Seed Inspection

  • Seed lot sampling done before and after processing of seeds
  • Seed testing for seed viability, health, germination and purity

Factors affecting seed storage

  • Kind/variety of seed
  • Initial seed quality
  • Seed Moisture
  • Humidity
  • Temperature
  • Oxygen content
  • Storage condition

Types of seeds:

Breeder seed: Seed/vegetative propagating material which is directly controlled b originating breeders/institution and which provides fr the initial and recurring increase of foundation seed. The genetic purity is rigidly maintained. In self pollinated species, mass selection is often practiced to retain the genetic purity. It is also the source of all other classes of seeds.

Foundation seed: seed stock so handled to maintain specific genetic identity and purity that may be designated/distributed by an agricultural experimental station. Carefully observed, supervised and approved by representatives of the station. It is the responsibility of national and state seed corporations to produce the seeds.

Registered seed: progeny of the foundation seed/so handled to maintain genetic purity and purity and has been approved and certified y a certifying agency. Its quality should be suitable for production of certified seeds. It is usually produced by progressive farmers according to technical advice and supervision provided by NSC. Often registered seed is omitted and certified seed is produced directly from foundation seed.

Certified seed: Progeny of foundation/registered seed that is so handled to maintain satisfactory genetic identity and purity and that has been approved by certifying agency. Certified see is annually produced progressive farmers according to standard seed production practices. To be certified, seed must meet certain rigid requirements regarding purity and quality. It is available for general distribution to farmers for commercial crop production.

Requirements of certified seed

  • Seed must be of an improved variety
  • Seeds to contain standard genetic and physical qualities as required
  • Germination percentage prescribed for various crops ranges from 80-90 per cent
  • Certified seeds must be free from noxious weeds, diseases and pests
  • Seeds to contain optimum moisture content which does not affect its germination and storage.
National Seed Corporation (NSC)

A body of government undertaking was set up in 1963.
  • It plans for the production of breeder seed in consultation with ICAR and organizes the production of foundation seed.
  • It is responsible for inter-state marketing of certified seeds.
  • It conducts biennial surveys of seed demand plan.
  • Coordinates research and sales promotion efforts.
  • Provides technical assistance to seed corporations and private sector agencies, training facilities for staff participating in seed industry development and also provides certification services for states not having established independent seed certification agencies.
NSC is looked upon as an agency which would promote the industry in India, initiate measures leading to production for high quality seed and in particular produce, process and market seeds. It has been given the primary responsibility for establishing an adequate system of quality control inspection and for promoting scientific seed processing, storage and marketing.

Seed Processing

It refers to all the steps necessary for preparation of harvested seed for marketing. Seed processing becomes necessary because the seed lots received from the field are often at high moisture content and contain trash and other inert material, weed seeds, deteriorated and damaged seeds etc. Following are some of the processing techniques followed after harvesting the seeds.
1.    Seed drying: mainly to remove the moisture so as to store the seeds for long period and also to maintain the viability of seeds. Seeds can be subjected to sun drying and forced air drying.
2.    Seed Cleaning: Separation of undesirable material namely, inert matter, weed seeds, other crop seeds, light and chaffy seeds, damaged and deteriorated seeds from desirable material.
3.    Seed grading by removing the smaller and shriveled seeds from healthy one.
4.    Seed treatment with fungicides, insecticides or combination of both to prevent seed borne or soil borne pathogens and pests.
5.    Seed packing (gunny bags) and handling (transport)

No comments:

Post a Comment