Scholarlink

<p>A reasonable plant density is one of the most effective ways to increase crop yields without increasing the cultivated area. But high - density planting changes the light intensity and quality, especially the ratio of red to far - red light (R/FR). This directly affects the photosynthetic performance of tobacco plants. To investigate the effects of such altered light conditions on photosynthetic characteristics and their underlying mechanisms, this study simulated dense planting environments using different proportions of FR. The results demonstrated that a high proportion of far-red light (HFR) significantly increased the net photosynthetic rate, stomatal conductance, chlorophyll content, and levels of photosynthetic products in tobacco, suggesting a positive regulatory effect on photosynthesis. Chlorophyll fluorescence analysis revealed enhanced PSII photochemical efficiency and reduced non-photochemical quenching, indicating more efficient utilization of light energy. These improvements were primarily attributed to HFR-induced increases in chloroplast number and optimization of thylakoid membrane structure, thereby enhancing overall photosynthetic capacity. At the molecular level, HFR can make the phytochrome genes <i>NtPHYA</i> express more. It can also upregulate the chloroplast division - related genes <i>NtPDV1</i>, <i>NtPDV2</i>, and <i>NtARC5</i>. All these genes work together to promote the growth of chloroplasts and improve photosynthetic efficiency. These findings elucidate the multi-level regulatory role of FR in improving tobacco leaf photosynthesis and provide a theoretical foundation for optimizing light environments to support high-density cropping systems and improve agricultural productivity.</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

Study on the Effects and Mechanisms of Far-red Light on Photosynthetic Characteristics in Tobacco (Nicotiana tabacum L.)

  • 期刊论文

  • 发表日期：

    2026年6月2日

查看全文
  • Can Lei,
  • Yu Xie,
  • Lei Liu,
  • Zhi Zhou

摘要

A reasonable plant density is one of the most effective ways to increase crop yields without increasing the cultivated area. But high - density planting changes the light intensity and quality, especially the ratio of red to far - red light (R/FR). This directly affects the photosynthetic performance of tobacco plants. To investigate the effects of such altered light conditions on photosynthetic characteristics and their underlying mechanisms, this study simulated dense planting environments using different proportions of FR. The results demonstrated that a high proportion of far-red light (HFR) significantly increased the net photosynthetic rate, stomatal conductance, chlorophyll content, and levels of photosynthetic products in tobacco, suggesting a positive regulatory effect on photosynthesis. Chlorophyll fluorescence analysis revealed enhanced PSII photochemical efficiency and reduced non-photochemical quenching, indicating more efficient utilization of light energy. These improvements were primarily attributed to HFR-induced increases in chloroplast number and optimization of thylakoid membrane structure, thereby enhancing overall photosynthetic capacity. At the molecular level, HFR can make the phytochrome genes NtPHYA express more. It can also upregulate the chloroplast division - related genes NtPDV1, NtPDV2, and NtARC5. All these genes work together to promote the growth of chloroplasts and improve photosynthetic efficiency. These findings elucidate the multi-level regulatory role of FR in improving tobacco leaf photosynthesis and provide a theoretical foundation for optimizing light environments to support high-density cropping systems and improve agricultural productivity.