遮阴处理对白簕生长与光合特性的影响

目的]探讨遮阴环境对白簕生长与光合特性的影响。方法]以当年生白簕幼苗为试材,比较不同光照条件(100%、39%、21%和6%)对白簕的生长状况和光合特征指标的影响。结果]随着光照强度的降低,白簕的株高、基径、叶片数、茎生物量、叶生物量和总生物量等生长指标均呈先增加后降低的趋势,最大净光合速率、表观量子效率、相对叶绿素含量、PSⅡ最大光能转化效率Fv/Fm和PSⅡ植物叶片潜在活性Fv/Fo等光合特性也呈先增加后降低的趋势,且在21%处理下达到最大值。光补偿点、光饱和点和暗呼吸速率随着遮阴强度的增加而降低。结论]光照太强(100%)或太弱(6%)均不利于植株生长,只有光照控制在自然光的21%左右时,植株生长最佳。

Effects of Different Shade Conditions on the Growth and Photosynthetic Characteristics of Acanthopanax trifoliatus

Objective] To discuss effects of shading conditions on growth and photosynthetic characteristics of Acanthopanax trifoliatus（L.） Merr.Method] Choosing 1 year old seedling as test materials,the effects of light intensity on growth and photosynthetic characteristics of Acanthopanax trifoliatus（L.） Merr under different treatments（100%,39%,21%,6% of full light） were compared.Result]With the reduction of light intensity,the plant height,stem basal diameter,leaf number,stem biomass,leaf biomass,total biomass,maximum net photosynthetic rate,apparent quantum efficiency,relative chlorophyll content,PS Ⅱ maximum light conversion efficiency Fv/ Fo and PS Ⅱ plant leaves potential activity of Fv/ Fo of the Acanthopanax trifoliatus（L.） Merr increased first and decreased later,and reached the biggest value under 21% treatment.The light compensation point,light saturation point and dark respiration rate enhanced with the increase of shade degree.Conclusion]The results suggested that the light intensity is too strong and the weak（100% and 6% of full sunlight） are not conducive to plant growth,only when the light was controlled at 21% of full sunlight,the Acanthopanax trifoliatus（L.） Merr seedlings grew well.