Marker assisted selection in black cross progenies of prathyasa and aiswarya pyramided with 2 R genes against BLB in rice(Oryza sativa L.)

Abstract

Bacterial leaf blight disease of rice caused by Xanthomonas oryzae pv. oryzae (Xoo) is one of the most devastating diseases of rice in the world. Major rice-growing countries are affected by this disease leading to losses of up to 80% in susceptible cultivars. The exploitation of host plant resistance is the most suitable practical strategy for disease management in an eco-friendly manner. To date, about 42 BLB resistance genes, conferring resistance against various strains of Xoo, have been identified from the rice germplasm collections worldwide. So, the present study entitled “Markerassisted selection in back cross progenies of Prathyasa and Aiswarya pyramided with 2 R genes against resistance to bacterial leaf blight in rice (Oryza sativa L.)” was undertaken at the College of Agriculture, Vellayani during 2018-2022 to develop and evaluate BC3F1 and BC3F2 progenies of Prathyasa and Aiswarya pyramided with two R genes (xa13 and Xa21) from the donor ISM (Improved samba Mahsuri). The morphometric traits of pyramided lines and recurrent parents were almost similar and yield contributing characteristics such as panicle length, the number of productive tillers per plant, and other traits were improved in the lines. Aiswarya and Prathyasa are the two high-yielding varieties of the major rice-growing regions Palakkad and Kuttanad. Hence the lines developed in the background of these varieties will overcome the susceptibility to BLB and can be cultivated in the tracts prone to the incidence of BLB. The pyramided lines are having high recovery of recurrent parent genome and they can be released as essentially derived varieties or can be incorporated as donor parents in the breeding programs