Genetic Engineering for Biotic Stress Management in Rice

Rice yield is affected by various biotic stresses including fungi, bacteria, viruses, parasites, nematodes, weeds and insects, posing a major threat to global food security. Therefore, one of the major objectives of rice breeders is to develop rice cultivars resistant to biotic stresses and it has been achieved to large extent through traditional and molecular breeding approaches. However, frequent breakdown of resistance to these biotic stresses is a challenging issue and therefore, continuous efforts are needed to develop cultivars with durable resistance. Recently, genetic engineering technologies like transgenics and RNAi have enabled breeders to develop such durable resistance in rice against number of bacterial, fungal and viral diseases by utilizing the genes conferring resistance to trait and isolated from various organisms like plants, animals, microbes, etc. Genetic engineering is more preferred in some of the cases as it has advantages like requirement of lesser duration, no linkage drag and no crossing barrier compared to molecular breeding. Although varieties developed through genetic engineering require prior regulation before commercialization, it has the enormous potential to develop plants resistant/tolerant to biotic stresses. Present status of use of genetic engineering for developing biotic stress resistance in rice is briefly described in this chapter.