Straw mulch-based no-tillage improves tillering capability of dryland wheat by reducing asymmetric competition between main stem and tillers

• DOI: 10.1016/j.cj.2021.09.011
• Publication Date: 2021-12-27T17:30:18Z
• Authors: Hongkun Yang; Yun Xiao; Peng He; Dailong Ai; Qiaosheng Zou; Jian Hu; Qiong Liu; Xiulan Huang; Ting Zheng; Gaoqiong Fan
• Keywords: Tiller (botany); Drought Tolerance

The moisture-conserving effect of straw mulch-based no-tillage (SMNT) is expected to increase fertile spikes and grain yield in environments with rainfall less than 200 mm. However, the mechanisms underlying positive SMNT on wheat tillering are not fully elucidated. A split-plot experiment was designed investigate combined effects cultivars dryland grown under both dry favorable climates. Application a cultivar 1–2 tillers exploited kernel-number plasticity, increasing mean by 20.5%. This attributed primarily an increased first-tiller emergence rate resulting from N uptake, leaf content, remobilization their grain. second third tillers, as transient sinks, contributed tiller survival rate, which depends number. total uptake also mass C:N ratio, reducing asymmetric competition between main stem tillers. Owing these beneficial effects, reduced mitogen-activated protein kinase (MAPK) abscisic acid signals were observed SMNT, whereas indole-3-acetic (IAA) genes involved DNA replication mismatch repair increased. These activated three critical transcription factors (the calmodulin-binding activator, GRAS domain, cysteine-2/histidine-2 family) further rapid drought response maintenance after extension. Phenylpropanoid biosynthesis, sphingolipid galactose metabolism most relevant because role lignin biosynthesis. Our results suggest that activates improved coordinating root remobilization,