Rice breeding strategies of North Eastern India for resilience to biotic and abiotic stresses: A review

摘要

In north eastern region, rice is grown in diverse agro-climatic conditions viz., upland, jhum, terraces, lowland and deep water. The region is considered to be a hot spot for rice diversity and have reported to have valuable landraces, wild rice and primitive cultivars. The major rice production constraints in the region are large acreage under traditional cultivars, biotic and abiotic stresses, and lack of wide scale technological intervention. Among abiotic stresses, soil acidity, iron toxicity, aluminium toxicity, low light intensity, low temperature, flooding and moisture deficit stress are the major problems that lead to lower productivity of rice. Under biotic stress, rice blast is the major disease that ultimately affects rice in all the rice growing ecosystem of the region and cause huge economic loss. Hence, it would be logical to prioritize the rice research on the basis of prevailing constraints under rainfed areas of north eastern India.Breeding of suitable rice varieties by exploitation of landraces and local cultivars adapted to the regions would be the most sustainable strategy to boost rice production. A systematic collection, conservation, characterization and documentation of rice germplasms for resistance to stresses, grain qualityand other agronomic important traits will accelerate the successful utilization of the germplasms in classical and innovative rice breeding work.