Phytochrome B interacts with LIGULELESS1 to control plant architecture and density tolerance in maize  

作　　者：Qingbiao Shi Ying Xia Qibin Wang Kaiwen Lv Hengjia Yang Lianzhe Cui Yue Sun Xiaofei Wang Qing Tao Xiehai Song Di Xu Wenchang Xu Xingyun Wang Xianglan Wang Fanying Kong Haisen Zhang Bosheng Li Pinghua Li Haiyang Wang Gang Li 

机构地区：[1]State Key Laboratory of Wheat Improvement,College of Life Sciences,Shandong Agricultural University,Tai'an 271018,China [2]State Key Laboratory of Wheat Improvement,College of Agronomy,Shandong Agricultural University,Tai'an 271018,China [3]Peking University Institute of Advanced Agricultural Sciences,Shandong Laboratory of Advanced Agricultural Sciences at Weifang,Weifang,Shandong 261000,China [4]Guandong Laboratory for Lingnan Modern Agriculture,State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources,South China Agricultural University,Guangzhou510642,China

出　　处：《Molecular Plant》2024年第8期1255-1271,共17页分子植物（英文版）

基　　金：the National Natural Science Foundation of China(32270263 to G.L.,32130077 to H.W.,and 32272140 to P.L.);the Shandong Provincial Natural Science Foundation(ZR2022QC095,ZR2020MC023,ZR2022MC019).

摘　　要：Over the past few decades,significant improvements in maize yield have been largely attributed to increased plant density of upright hybrid varieties rather than increased yield per plant.However,dense planting triggers shade avoidance responses(SARs)that optimize light absorption but impair plant vigor and performance,limiting yield improvement through increasing plant density.In this study,we demonstrated that high-density-induced leaf angle narrowing and stem/stalk elongation are largely dependent on phytochrome B(phyB1/B2),the primaryphotoreceptor responsible for perceiving red(R)and far-red(FR)light in maize.We found that maize phyB physically interacts with the LIGULELESS1(LG1),a classical key regulator of leaf angle,to coordinately regulate plant architecture and density tolerance.The abundance of LG1 is significantly increased by phyB under high R:FR light(low density)but rapidly decreases under low R:FR light(high density),correlating with variations in leaf angle and plant height under various densities.In addition,we identified the homeobox transcription factor HB53 as a target co-repressed by both phyB and LG1 but rapidly induced by canopy shade.Genetic and cellular analyses showed that HB53 regulates plant architecture by controlling the elongation and division of ligular adaxial and abaxial cells.Taken together,these findings uncover the phyB-LG1-HB53 regulatory module as a key molecular mechanism governing plant architecture and density tolerance,providing potential genetic targets for breeding maize hybrid varieties suitable for high-density planting.

关 键 词：MAIZE phytochrome B LIGULELESS1 HB53 leaf angle density tolerance 

分 类 号：S513[农业科学—作物学]