Light-hormone crosstalk modulates vegetative branching and yield stability in dual-planting cotton systems

• 全文链接

光激素串扰对双种植棉花营养分枝和产量稳定性的调控

关键词：

来源：

FIELD CROPS RESEARCH

全文链接：

//agri.nais.net.cn/topic/downloadFile/184ffa08-c13f-4647-9d01-4529cb87e93a

来源地址：

https://www.sciencedirect.com/science/article/pii/S0378429025003685?via%3Dihub

资源所属：

棉花遗传育种

类型：

学术文献

语种：

英语

原文发布日期：

2025-11-01

摘要：

Context: Dual-planting systems, characterized by retaining two seedlings per hole, offer a labor-efficient strategy for cotton cultivation by suppressing vegetative branching (VB) without compromising yield. However, the mechanisms underlying VB inhibition and yield stability remain poorly resolved. Method: This study integrates ecological, physiological, and molecular approaches to unravel how light-hormone crosstalk modulates branching plasticity in dual-planting cotton. Field trials comparing single- (1S) and dualplanting (2S) systems were conducted over two seasons, coupled with canopy microclimate analysis, stable isotope (13C) tracing, transcriptomics, and hormonal profiling. Results: Results demonstrated that dual-planting reduced VB-sourced boll density by 56.3 % while increasing fruiting branch (FB)-sourced yield by 12.9 %, maintaining total seed cotton yield parity with 1S. Canopy restructuring under 2S lowered photosynthetically active radiation (PAR) and red/far-red (R/FR) ratios at VB positions by 45.5-55.6 % and 38.4 %, respectively, intensifying light competition. This activated the phyB-PIFsBRC1 signaling axis, triggering hormonal reconfiguration: suppressed auxin (IAA; 22.1 %) and cytokinin (CTKs; 24.3-52.2 %) levels alongside elevated jasmonate (JA; 49.7 %) and abscisic acid (ABA; 27.8 %). VB biomass correlated positively with PAR and growth-promoting hormones (IAA, CTKs) but negatively with ABA. Transcriptomic analysis revealed downregulation of photosynthesis-related genes (GhLHCB, GhPHYB) and growthpromoting pathways (GhYUC8, GhIPT1), alongside upregulation of stress-responsive genes (GhLOX1, GhPYL9). Concurrently, 13C tracing showed preferential photoassimilate allocation to FBs, enhancing fiber quality (7.3 % longer, 12.4 % stronger fibers) without yield loss. Conclusion: These findings establish a tripartite regulatory framework linking canopy ecology, hormonal dynamics, and light signaling to optimize resource partitioning. By elucidating the molecular basis of branching plasticity, this work provides actionable insights into breeding shade-resilient cultivars and refining high-density planting systems, advancing sustainable cotton production under labor-constrained scenarios.