Logo

Crop Variety Improvement


CROP VARIETY IMPROVEMENT


  • This approach is based on selecting the crop that can provide us good yield with desirable features or incorporating the desirable features into the growing crops. Technique is followed with different aim and through different ways.

  • Some of the features for which crops are improved are:
  • Higher yield: crops are improved with the aim for increasing the productivity per acre in different sets of environmental conditions.
  • Improved quality: quality considerations vary from crop to crop as per the requirements.
  • Example: protein in pulses, baking quality in wheat, oil content in oil seeds etc.
  • Resistance: Production and quality of crops are maintained if they can resist different stress factors. For this crops should be improved for better resistance towards the diseases or other damage caused by biotic factors like bacteria, virus, insects, nematodes etc. Also they must be improved so as to tolerate different abiotic stresses like heat, cold, frost, salinity, water logging, draught etc.
  • Change in maturity duration: Life cycle of crops runs between sowing to harvesting. Short duration of life cycle is desirable in crops so that farmers can grow the multiple rounds of same crop in same season on same piece of land. This will therefore increase the production of crop as well as the economic condition of farmers and the country. Thus the improvement for short life cycle in crop plants is desirable.
  • Wider adaptability: plants should be improved in a way that they grow and easily adapt to different sets of climatic conditions in different area all through the country.
  • Desirable agronomic characteristics: agronomic characteristic is related to the specific character in a particular type of crop.
  • Example: Tallness and profuse branching for fodder crops to increase the fiber content in it; Dwarfness is desired for cereals to decrease the absorption of nutrients from the soil etc.

 

Methods of crop variety improvement:

Hybridization:

  • Hybridization is the process of crossing two genetically different individuals to result in a third hybrid individual with a different, often preferred, set of traits/ characters.
  • For this two plants with desirable set of characters are selected and cross pollinated. As a result of this the new plant produced will have the characters of both the parents.

  • It is of three types.
  • Intervarietal: Cross between different varieties of plants.
  • Example: two varieties of wheat one is disease resistant and the other is high yielding. Crossing/hybridization may result in a variety that is both high yielding and disease resistant.
  • Interspecific: Plants belonging to two different species of the same genus are crossed.
  • Example: Several disease, pest and drought resistant varieties of wheat, tomato, sugarcane etc have been evolved by this method.
  • Intergeneric: Plants belonging to two different genera (singular genus) are crossed.

 

Genetic manipulation:

  • It means the introduction of new gene coding for desirable character into the crop plant by using scientific methods. Improved plants/ organisms produced by this technique are known as genetically modified organisms [GMO’s] or transgenic plants.
  • Example: Bt cotton, herbicide resistant soya bean, insect resistant corn plant etc.