PREMATURE SENESCENCE LEAF 50 Promotes Heat Stress Tolerance in Rice (Oryza sativa L.)

Abstract Background Heat stress is a major environmental factor that could induce premature leaf senescence in plants. So far, a few rice premature senescent leaf mutants have been reported to involve in heat tolerance. Findings We identified a premature senescence leaf 50 ( psl50 ) mutant that exhibited a higher heat susceptibility with decreased survival rate, over-accumulated hydrogen peroxide (H 2 O 2 ) content and increased cell death under heat stress compared with the wild-type. The causal gene PREMATURE SENESCENCE LEAF 50 ( PSL50 ) was isolated by using initial map-based resequencing (IMBR) approach, and we found that PSL50 promoted heat tolerance probably by acting as a modulator of H 2 O 2 signaling in response to heat stress in rice ( Oryza sativa L.). Conclusions PSL50 negatively regulates heat-induced premature leaf senescence in rice.