Natural variations at the Stay-Green gene promoter control lifespan and yield in rice cultivars
Dongjin Shin, Sichul Lee, Tae‐Heon Kim, Jong‐Hee Lee, Joonheum Park, Jinwon Lee, Ji Yoon Lee, Lae‐Hyeon Cho, Jae Young Choi, Wonhee John Lee, Ji-Hwan Park, Dae‐Woo Lee, Hisashi Itô, Dae Heon Kim, Ayumi Tanaka, Jun Hyeon Cho, You‐Chun Song, Daehee Hwang, Michael D. Purugganan, Jong‐Seong Jeon, Gynheung An, Hong Gil Nam
Abstract
Abstract Increased grain yield will be critical to meet the growing demand for food, and could be achieved by delaying crop senescence. Here, via quantitative trait locus (QTL) mapping, we uncover the genetic basis underlying distinct life cycles and senescence patterns of two rice subspecies, indica and japonica . Promoter variations in the Stay-Green ( OsSGR ) gene encoding the chlorophyll-degrading Mg ++ -dechelatase were found to trigger higher and earlier induction of OsSGR in indica , which accelerated senescence of indica rice cultivars. The indica -type promoter is present in a progenitor subspecies O. nivara and thus was acquired early during the evolution of rapid cycling trait in rice subspecies. Japonica OsSGR alleles introgressed into indica -type cultivars in Korean rice fields lead to delayed senescence, with increased grain yield and enhanced photosynthetic competence. Taken together, these data establish that naturally occurring OsSGR promoter and related lifespan variations can be exploited in breeding programs to augment rice yield.