Identification of sheath blight tolerant lines through detached leaf method in samba mahsuri (BPT-5204) rice variety

Abstract

Rice is an important staple food crop and primary diet source for majority of the world’s population. However, biotic stress such as Sheath blight (ShB) is one of major disease which effects 50-60% yield loss. ShB disease is mainly caused by Rhizoctonia solani, however, no rice cultivar has been found to be completely tolerance. We developed the BPT5204 mutant lines through EMS method. The mutant lines (BPT5204) were screened through detached leaf method (Dath 1987) under standard glass house conditions and the protocol was standardized in ICAR-IIRR. After 72hrs of infection, the lesion length of each cut leaf was measured and according to tolerance we scored 0-9 scale. We observed that 13 out of 40 were showed tolerance against sheath blight. ShB-1, ShB-5, ShB-11, ShB-12, ShB-13 (score-0) lines were showed highly tolerance, ShB-2 and ShB-8 (score 1-8) were moderately tolerant, wild type (BPT5204) was complete susceptible (scores up to 9). Therefore, this standardized detached leaf assay can be used to assess against sheath blight disease.