Effects of light and water availability on the growth of Aglaia duperreana seedlings
Aglaia duperreana,a species with a long cultivation history,is of high omamental value.To understand the growth and photosynthetic changes of A.duperreana seedlings under variable environmental conditions,we con-ducted an experiment with light intensities adjusted at 70％,50％ and 30％,crossed with three moisture treatments at 70％,50％ and 30％ of field capacity,and a control group which maintained 90％ light intensity and 90％ field capacity.The results showed that both drought stress and shading propensity significantly inhibited the growth of A.duperreana seedlings,with stronger impacts from drought stress.The increments in stem height and ground diame-ter,net photosynthetic rate,transpiration rate,stomatai conductance,and chlorophyll content were decreased with the maximum declines by 71.4％,81.2％,93.2％,71.5％,70.6％ and 30.4％,respectively.Under severe drought stress(30％ of field capacity),partial shading(50％ of translucency)appeared to lessen the detrimental effects of drought.The combination of 70％ translucency and 70％field capacity was optimal,resulting in higher increments in stem height,leaf area,net photosynthetic rate,transpiration rate,and stomatal conductance.The maximum fluo-rescence,variable fluorescence,PS Ⅱ potential activity,and PS n maximum light energy conversion efficiency increased and then decreased with decreasing moisture.These findings suggested that A.duperreana could adapt to drought and shading stress by modulating growth,enhancing chlorophyll content,and adjusting photosynthetic sys-tem.Maintaining translucency at 70％and field moisture capacity at 70％could promote photosynthesis,with posi-tive consequences on growth of A.duperreana.
万方数据
维普
