不同光质补光对辣椒幼苗生长、丛枝菌根共生和磷吸收的影响

Effects of Supplemental Lighting on Growth,Root Colonization by Arbuscular Mycorrhizal Fungi and Phosphorus Uptake in Pepper Seedlings

以‘博辣红帅’辣椒(Capsicum annuum L.)为材料,探究了幼苗期不同光质补光对其生长、光合特性、碳水化合物积累、丛枝菌根真菌(AMF)定殖以及磷吸收的影响。结果表明:与对照白光(WL)相比,补充红光(R)和蓝光(B)均能显著增加辣椒幼苗生物量和壮苗指数;与补充蓝光相比,补充红光对叶片光饱和光合速率、光合色素积累、根系中总糖含量、蔗糖比重以及独脚金内酯(SL)含量的促进效果更为明显。同时,幼苗期补充红光和蓝光均能显著促进后续白光和缺磷条件下AMF的定殖和辣椒干物质积累,并提高根系SL含量、PT4、PT5基因表达以及植株磷含量,以补充红光效果更为明显。以上结果表明,辣椒幼苗期补充红光有利于幼苗生长以及碳水化合物、SL在根部的积累,进而对后续缺磷条件下AMF的定殖以及幼苗对磷的吸收具有明显的促进作用。

In the current study,the pepper(Capsicum annuum L.)cultivar‘Bola Hongshuai’was used to explore the effects of supplemental lighting on the growth,photosynthetic characteristics,carbohydrate accumulation,root colonization by arbuscular mycorrhizal fungi(AMF),and phosphorus absorption at the seedling stage.The results showed that compared with the control,supplemental red and blue light could significantly increase the biomass and seedling index of pepper seedlings;however,compared with the supplemental blue light,supplemental red light had more profound stimulating effects on the light-saturated photosynthetic rate,the accumulation of photosynthetic pigments,and the proportion of total sugar and sucrose content in the roots.Notably,red and blue light treatments were both conducive to the accumulation of strigolactones in roots but the former was more obvious.Moreover,supplementation of red and blue light during the seedling stage significantly promoted the colonization of roots by AMF and increased the dry weight,the accumulation of strigolactone content in roots,the expression of PT4 and PT5 genes,the phosphorus content and phosphorus concentration in pepper under the following condition of white light and phosphorus deficiency.However,compared with other light conditions,these responses were more profound when supplemented with red light.Taken together,the study revealed that supplementation of red light during the seedling stage was the most beneficial to the growth of pepper seedlings,and the accumulation of carbohydrates and strigolactones in the roots,which in turn promoted the colonization of roots by AMF and the phosphorus absorption in pepper seedlings.