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Details Of Innovation
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A remarkably rich diversity exists among the cultivated rice and their wild relatives found in Kerala, South India. Today in Kerala, farmers are growing land races only in isolated pockets and although some land races have been collected now and then, and stored in gene banks, many have disappeared forever in the wake of modern agriculture. As the ‘unwanted’ land races were discarded, the valuable gene flow between land races and wild relatives diminished, in a sense freezing the natural evolutionary process. The continuous use of crops of the same gene source and cytoplasm has resulted in homogeneity in varieties. Yet the more widely grown variety becomes, more prone to the disease and insect pests breaking down of the resistance. Thus, the breeders run a race against time, trying to keep one step ahead of the rapidly evolving pests and diseases. During the three main crop seasons in Kerala viz. Virippu or Kharif, Mundakan or Rabi and Puncha or Summer about two hundred local varieties are grown. They are largely adapted to the particular human and environmental influences confronting them. They also possess special traits like resistance to biotic and abiotic stresses, ability to survive extreme agro edaphic conditions. These traditional rice varieties offer a pool of resistant genes against insect pests like brown plant hopper, green leaf hopper, gall midge, leaf folder, stem borer etc., and diseases like sheath blight, sheath rot, foot rot, blast etc., that cause considerable damage to the rice crop. Among them, varieties like ‘karivennel’, ‘kochuvithu orpandy’, ‘veluthacheera’, ‘orumu-ndakan’ have been used in breeding programmes at the global level. In the same way, varieties like‘thekkan’,‘vattan’,‘kavunginpoothala’ are known for their good cooking quality, suitability for processed items like beaten rice and puffed rice. Others like njavara, raktasali and dandakani are famous for their medicinal value. These varieties can form the building block in many crop improvement programmes since they act as donors of valuable genes. The few collections made in the past still fall short of the full spectrum necessary to meet future needs.
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