不同基因型辣椒光合及生长特性对弱光的响应

通过遮光使光照强度降低65%～70%，以研究弱光条件对不同基因型辣椒光合特性、同化物分配、产量形成和幼苗生长的影响.结果表明：弱光下辣椒净光合速率（P_n）、暗呼吸速率（R_d）、夜间呼吸速率（R_n）、蒸腾速率（T_r）、水分利用效率（WUE）、光补偿点（LCP）、CO₂补偿点（CCP）和羧化效率（CE）下降，表观量子效率（AQY）上升.弱光下辣椒成株期光合作用的限制因素是非气孔因素.弱光处理使辣椒幼苗高/粗比和比叶面积增加，根/冠比、全株干样质量及壮苗指数显著下降.弱光显著抑制了辣椒生物产量与经济产量的形成，使植株同化物向茎叶的分配比例增加，向果实的分配比例减少.辣椒（果实味辣）在弱光下具有较低的光补偿点，以及较高的相对壮苗指数、相对单株产量和相对坐果率，耐弱光性普遍强于甜椒（果实味甜）.

Photosynthetic and growth characteristics of different ecotype capsicum under weak light

This paper studied the effects of weak light on the photosynthetic characteristics,assimilates allocation,yield formation,and seedling growth of different ecotype capsicum(hot pepper and sweet pepper).The results showed that under weak light,the net photosynthetic rate(P_n),dark respiration rate(R_d),night respiration rate(R_n),transpiration rate(T_r),water use efficiency(WUE),light compensation point(LCP),CO_2 compensation point(CCP)and carboxylation efficiency(CE)of test capsicums decreased,while their apparent quantum yield(AQY)increased.The decrease of P_n was considered as a result of non-stomata restriction.Weak light increased plant height/stem diameter ratio and specific leaf area,but decreased root/shoot ratio,total dry mass,and seedling's healthy index.Under the effect of weak light,the formation of biological and economic yields was inhibited significantly,and the allocation of assimilates to stem and leaf was increased while that to fruit decreased.Hot pepper under weak light had lower light compensation point,higher relative healthy index,higher relative yield per plant,and higher relative setting rate,showing a stronger capability of weak light tolerance than sweet pepper.