Marker-assisted selection for sheath blight resistance in rice (Oryza sativa L.)

Abstract

Sheath blight is one of destructive diseases of rice, causing substantial loss to rice production. Developing resistant cultivars to sheath blight is quite difficult due to lack of effective resistant source in the available germplasm. Pyramiding of gens/QTLs for different biotic stresses gives broad-spectrum resistance to multiple diseases for any crop. The present study was carried out to introgress sheath blight resistant QTL, qSBR11-1, into the backgrounds of CB14004 and CB14002 from the donor parent Tetep. CB14004 and CB14002 are the two bacterial blight resistant genotypes, pyramided with three bacterial blight resistant genes viz., xa5, xa13 and Xa21. The positive plants of BC3F1 individuals for sheath blight QTL i.e., qSBR11-1were self-pollinated to generate BC3F2 individuals. The BC3F2 individuals were screened with linked molecular marker of qSBR11-1 i.e., RM 224 and the confirmed plants were assessed for morphological traits to identify the superior segregates.