Department of Agricultural Sciences, University of Naples Federico II, Portici, Italy.
Elevate Farms, Inc., Toronto, Ontario, Canada.
Physiol Plant. 2021 Aug;172(4):2191-2202. doi: 10.1111/ppl.13395. Epub 2021 Mar 23.
Characterizing spectral effects of blue and red light ratios on plants could help expand our understanding of factors that regulate growth and development, which is becoming increasingly important as narrowband light-emitting diodes become common for sole-source lighting. Herein we report growth, physiological, and anatomical responses of two lettuce cultivars grown indoors under various blue and red ratios including monochromatic treatments. When used in combination with red, increasing the proportion of blue light generally reduced growth but increased chloroplast abundance and single-leaf photosynthetic efficiency. However, when used as single wavebands, both blue and red light increased leaf area and epidermal cell area, but reduced root dry mass, SPAD index, stomatal density, and leaf thickness compared to dichromatic light. In addition, chloroplast abundance and single-leaf physiological responses were higher in plants grown under monochromatic blue compared to red light, but the opposite trend was measured for shoot biomass. Our results show that spectral effects on morpho-anatomical leaf responses can largely influence plant growth and single-leaf physiological responses. However, a significant blue light reduction in radiation capture ultimately limits growth and productivity of lettuce plants when dichromatic blue and red light is used.
描述蓝光和红光比例对植物的光谱效应可以帮助我们扩展对调节生长和发育的因素的理解，随着窄带发光二极管成为单一光源，这一点变得越来越重要。本文报告了在室内种植的两种生菜品种在不同蓝光和红光比例下的生长、生理和解剖反应，包括单色处理。当与红光结合使用时，增加蓝光的比例通常会降低生长速度，但会增加叶绿体的丰度和单叶光合效率。然而，当作为单一波段使用时，与双色光相比，蓝光和红光都会增加叶面积和表皮细胞面积，但会降低根干重、SPAD 指数、气孔密度和叶片厚度。此外，与红光相比，在单色蓝光下生长的植物的叶绿体丰度和单叶生理反应更高，但在茎生物量方面则呈现相反的趋势。我们的结果表明，光谱对形态解剖叶片反应的影响在很大程度上影响植物的生长和单叶生理反应。然而，当使用双色蓝光和红光时，辐射捕获的蓝光显著减少最终限制了生菜植物的生长和生产力。
