This study selected Dendrobium officinale protocorms as the experimental material and used different light-quality treatments and calcium signalling inhibitors to explore the mechanism of the biological response of calcium to light quality. The results indicate that a 1:3 red:blue (R:B) light ratio promotes the accumulation of biomass and polysaccharides in the protocorm. Nevertheless, this effect can be entirely counteracted by calmodulin (CaM) inhibitors and calcium ion-chelating agents. The possible mechanisms of this effect are as follows: (1) The Ca 2+ -CaM signal-regulated photosynthetic apparatus is improved by the R:B 1:3 light, increasing the CaM content and Ca 2+ -ATPase activity. Thus, R:B 1:3 light increases the development of the photosynthetic apparatus in the D. officinale protocorm, enhances its photosynthetic productivity, and promotes the activities of sucrose phosphatase; accordingly, biomass and sucrose accumulation increase. (2) R:B 1:3 light enhances Ca 2+ -CaM signalling and regulates glycometabolic processes to promote the activities of sucrose synthase, thus increasing fructose and glucose levels and providing sufficient synthetic precursors to promote polysaccharide production.

中文翻译：

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钙信号介导铁皮石斛原球茎光质对生长和多糖积累的调节

本研究选择铁皮石斛原球茎作为实验材料，采用不同的光质处理和钙信号抑制剂，探索钙对光质的生物反应机制。结果表明，1:3 的红:蓝 (R:B) 光比促进了原球茎中生物量和多糖的积累。然而，这种作用可以被钙调素 (CaM) 抑制剂和钙离子螯合剂完全抵消。这种效应的可能机制如下： (1) R:B 1:3 光改善了Ca 2+ -CaM 信号调节光合装置，增加了CaM 含量和Ca 2+ -ATPase 活性。因此，R:B 1:3 光促进了铁皮原球茎中光合器官的发育，提高了其光合生产力，并促进蔗糖磷酸酶的活性；因此，生物量和蔗糖积累增加。(2) R:B 1:3 光增强Ca 2+ -CaM 信号传导并调节糖代谢过程以促进蔗糖合成酶的活性，从而增加果糖和葡萄糖水平并提供足够的合成前体以促进多糖产生。