Light quality regulates plant biomass and fruit quality through a photoreceptor-dependent HY5-LHC/CYCB module in tomato

Increasing photosynthesis and light capture offers possibilities for improving crop yield and provides a sustainable way to meet the increasing global demand for food.However,the poor light transmittance of transparent plastic films and shade avoidance at high planting density seriously reduce photosynthesis and alter fruit quality in vegetable crops,and therefore it is important to investigate the mechanisms of light signaling regulation of photosynthesis and metabolism in tomato(Solanum lycopersicum).Here,a combination of red,blue,and white(R1W1B0.5)light promoted the accumulation of chlorophyll,carotenoid,and anthocyanin,and enhanced photosynthesis and electron transport rates by increasing the density of active reaction centers and the expression of the genes LIGHT-HARVESTING COMPLEX B(SlLHCB)and A(SlLHCA),resulting in increased plant biomass.In addition,R1W1B0.5 light induced carotenoid accumulation and fruit ripening by decreasing the expression of LYCOPENEβ-CYCLASE(SlCYCB).Disruption of SlCYCB largely induced fruit lycopene accumulation,and reduced chlorophyll content and photosynthesis in leaves under red,blue,and white light.Molecular studies showed that ELONGATED HYPOCOTYL 5(SlHY5)directly activated SlCYCB,SlLHCB,and SlLHCA expression to enhance chlorophyll accumulation and photosynthesis.Furthermore,R1W1B0.5 light-induced chlorophyll accumulation,photosynthesis,and SlHY5 expression were largely decreased in the slphyb1cry1 mutant.Collectively,R1W1B0.5 light noticeably promoted photosynthesis,biomass,and fruit quality through the photoreceptor(SlPHYB1 and SlCRY1)-SlHY5-SlLHCA/B/SlCYCB module in tomato.Thus,the manipulation of light environments in protected agriculture is a crucial tool to regulate the two vital agronomic traits related to crop production efficiency and fruit nutritional quality in tomato.

红光和远红光在调控植物生长发育及应答非生物胁迫中的作用

光作为重要的环境因子之一,不仅为植物光合作用提供能量,而且作为信号影响植物对外界环境的响应。该文综述了红光和远红光对植物生长发育和非生物胁迫响应的调控作用,重点阐述了光敏色素及下游光信号转录因子整合激素等内源信号调控植物种子萌发、下胚轴伸长、芽发育及开花的分子机制,以及红光和远红光在植物响应盐、干旱及温度胁迫中的作用机制。在挖掘植物感知和响应光环境机理的基础上,利用LED光谱技术对作物进行精确补光,有望提高作物产量、品质和抗逆性,同时推进实现“双碳”目标,减少能源消耗和环境污染。