<p><i>Oreorchis patens</i> is an endangered shade-adapted medicinal orchid whose pseudobulbs contain phenanthrenes with antitumor activity. Insufficient science-based light management has limited its artificial cultivation. We examined the effects of five sunlight transmittance (SLT) levels (3%, 23%, 46%, 74%, 90%) on photosynthetic traits, plant growth, and pseudobulb phenanthrene accumulation. Moderate shading at 46% SLT optimized net photosynthesis per leaf, pseudobulb biomass, root development, and leaf expansion. This treatment also yielded the highest per-unit-area phenanthrene yield, 93.5% higher than under 23% SLT. High light induced leaf chlorosis and premature senescence, whereas deep shade resulted in negative net photosynthesis; both extremes reduced survival rate. Our findings suggest that 46% SLT optimizes photosynthetic efficiency, biomass accumulation, and phenanthrene production, supporting light management for its cultivation.</p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

Moderate shading improves photosynthetic growth traits and phenanthrene production in Oreorchis patens

  • Zhenghai Zhang,
  • Jingjing Zhao,
  • Ye Hua,
  • Peihe Zheng,
  • Huixia Lei

摘要

Oreorchis patens is an endangered shade-adapted medicinal orchid whose pseudobulbs contain phenanthrenes with antitumor activity. Insufficient science-based light management has limited its artificial cultivation. We examined the effects of five sunlight transmittance (SLT) levels (3%, 23%, 46%, 74%, 90%) on photosynthetic traits, plant growth, and pseudobulb phenanthrene accumulation. Moderate shading at 46% SLT optimized net photosynthesis per leaf, pseudobulb biomass, root development, and leaf expansion. This treatment also yielded the highest per-unit-area phenanthrene yield, 93.5% higher than under 23% SLT. High light induced leaf chlorosis and premature senescence, whereas deep shade resulted in negative net photosynthesis; both extremes reduced survival rate. Our findings suggest that 46% SLT optimizes photosynthetic efficiency, biomass accumulation, and phenanthrene production, supporting light management for its cultivation.