A Novel Dominant Allele from 93-11, ES(4), Represses Reactive Oxygen Species Scavenging and Leads to Early-Senescence in Rice

Senescence is the last developmental process in plant, which has an important impact on crop yield and quality. In this study, a stable hereditary early-senescence line BC64 was isolated from high-generation recombinant inbred lines of 93-11 Wuyunjing7 (W7). Genetic analysis showed that premature aging phenotype controlled by dominant gene derived 93-11. By linkage analysis, primarily mapped region between marker B4 B5 near centromere chromosome 4, described as ES(4). Through multiple backcrossing with W7, near-isogenic ES(4) (NIL-ES(4)) obtained. Compared wild-type NIL-ES(4) plants more sever senescence both nature dark conditions. NIL plants, leaves turned yellow at fully tillering stage; photosynthetic rate, pollen fertility seed setting rate were decreased. Moreover, malondialdehyde, proline content relative conductivity significantly higher than those W7; transcript level activities reactive oxygen species scavenging enzymes repressed; H2O2 O2− accumulated. This study provides basis for further cloning function identification