Premature Senescence Leaf 50 Promotes Heat Stress Tolerance in Rice (Oryza Sativa L.)

Abstract

BackgroundHeat stress is a major environmental factor that could induce premature leaf senescence in plants. So far, few rice premature senescent leaf mutants have been reported to involve in heat tolerance.FindingsWe identified a premature senescence leaf 50 (psl50) mutant that exhibited a higher heat susceptibility with decreased survival rate, over-accumulated hydrogen peroxide (H2O2) 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 H2O2 signaling in response to heat stress in rice (Oryza sativa L.).ConclusionsPSL50 negatively regulates heat-induced premature leaf senescence in rice.

How rice adapts to high temperatures

“…Some studies have shown that grain filling is related to the overall thermotolerance of plants, and most thermosensitive lines show impaired grain filling under high-temperature stress (He et al, 2018;He et al, 2021). The loss-of-function mutants of ERECTA are thermosensitive, and their seeds are smaller than those of the wild type (WT) (Shen et al, 2015;Wu et al, 2022b).…”

“…The plants are short and prematurely senescent at heading stage (He et al, 2021). (He et al, 2021) OsGSK1 loss…”

“…In addition, the senescence rate of leaves, stomatal opening, and leaf temperature regulation might be used as an indicator to identify the thermotolerance of rice. PREMATURE SENESCENCE LEAF 50 (PSL50) mutant are highly sensitive to high temperatures (He et al, 2021). Inhibition of MONODEHYDROASCORBATE REDUCTASE (OsMDHAR4) expression enhances thermotolerance by inducing stomatal closure in rice plants (Liu et al, 2018).…”