Q. Genetic resources of biodiversity?
Genetic diversity or the gene pools are important for promoting and ensuring high agricultural yield. Genetic diversity provides crops with the flexibility needed for them to survive change s in the environment, which is especially important in view of the predicted global climate change in the foreseeable future. Crop diversification has resulted mainly due to the processes of natural selection in response to new ecological conditions, selec tion by farmers for particular characteristics over long periods of cultivation, and colonial expansion that resulted in the spread of crop species between countries and continents.
Wild relatives of crop species are important storehouses of crop genetic diversity. For example, farmlands in the Himalayan foothills of north-east India contain a large number of primitive rice cultivars that show resistance to major pests and diseases including bacterial blight, viruses, gall midge and the stem borer. An example is that a minimum of 50,000 varieties of rice have been grown in India until the very recent
past. The high crop diversity in South Asia is not accidental but due to the result of careful selection and even cross-breeding, over centuries, by the regions farmers to contend with different environmental conditions and needs.