Open AccessOverexpression of GmMYB14 improves high‐density yield and drought tolerance of soybean through regulating plant architecture mediated by the brassinosteroid pathway
Author(s) -
Chen Limiao,
Yang Hongli,
Fang Yisheng,
Guo Wei,
Chen Haifeng,
Zhang Xiaojuan,
Dai Wenjun,
Chen Shuilian,
Hao Qingnan,
Yuan Songli,
Zhang Chanjuan,
Huang Yi,
Shan Zhihui,
Yang Zhonglu,
Qiu Dezhen,
Liu Xiaorong,
Tran LamSon Phan,
Zhou Xinan,
Cao Dong
Publication year - 2021
Publication title -
plant biotechnology journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 3.525
H-Index - 115
eISSN - 1467-7652
pISSN - 1467-7644
DOI - 10.1111/pbi.13496
Subject(s) - brassinosteroid , biology , petiole (insect anatomy) , drought tolerance , myb , brassinolide , genetically modified crops , transactivation , abscisic acid , botany , transgene , abiotic stress , wilting , microbiology and biotechnology , transcription factor , arabidopsis , gene , biochemistry , mutant , plant growth , hymenoptera
Summary MYB transcription factors (TFs) have been reported to regulate the biosynthesis of secondary metabolites, as well as to mediate plant adaption to abiotic stresses, including drought. However, the roles of MYB TFs in regulating plant architecture and yield potential remain poorly understood. Here, we studied the roles of the dehydration‐inducible GmMYB14 gene in regulating plant architecture, high‐density yield and drought tolerance through the brassinosteroid (BR) pathway in soybean. GmMYB14 was shown to localize to nucleus and has a transactivation activity. Stable GmMYB14 ‐overexpressing ( GmMYB14‐OX ) transgenic soybean plants displayed a semi‐dwarfism and compact plant architecture associated with decreased cell size, resulting in a decrease in plant height, internode length, leaf area, leaf petiole length and leaf petiole angle, and improved yield in high density under field conditions. Results of the transcriptome sequencing suggested the involvement of BRs in regulating GmMYB14‐OX plant architecture. Indeed, GmMYB14‐OX plants showed reduced endogenous BR contents, while exogenous application of brassinolide could partly rescue the phenotype of GmMYB14‐OX plants. Furthermore, GmMYB14 was shown to directly bind to the promoter of GmBEN1 and up‐regulate its expression, leading to reduced BR content in GmMYB14‐OX plants. GmMYB14‐OX plants also displayed improved drought tolerance under field conditions. GmBEN1 expression was also up‐regulated in the leaves of GmMYB14‐OX plants under polyethylene glycol treatment, indicating that the GmBEN1 ‐mediated reduction in BR level under stress also contributed to drought/osmotic stress tolerance of the transgenic plants. Our findings provided a strategy for stably increasing high‐density yield and drought tolerance in soybean using a single TF‐encoding gene.