伯乐树幼苗对不同土壤含水量的生理生态响应  

Response of photosynthetic physiology of Bretschneidera sinensis seedlings to different soil water contents

作　　者：刘菊莲 夏丽芝[2] 郑伟成 季国华 叶飞英 胡有金 陶月良[3] 

机构地区：[1]浙江九龙山国家级自然保护区管理局,浙江遂昌323300 [2]温州科技职业学院,浙江温州325006 [3]温州大学生命与环境科学学院,浙江温州325035

出　　处：《中南林业科技大学学报》2015年第6期15-19,共5页Journal of Central South University of Forestry & Technology

基　　金：浙江省教育厅项目(Y2013117);遂昌县科技重点项目"珍稀濒危植物--伯乐树资源保护技术及示范推广"资金资助

摘　　要：为了明确伯乐树幼苗对土壤含水量的响应,比较研究了不同土壤含水量下伯乐树幼苗的形态学指标及相关光合参数。结果表明,在土壤相对含水量大于40%时,不同处理之间的蒸腾速率无显著差异(P>0.05);40%土壤含水量的条件下,水分利用效率和气孔限制值较高(P<0.05),而此时的表观光合速率、CO2利用效率和蒸腾速率均最低(P<0.05)。随着土壤含水量的降低,伯乐树幼苗叶片的最大光合速率(Pmax)、光补偿点(VLCP)、光饱和点(VLSP)、最大羧化速率(Amax)和羧化效率(RCU)整体上均呈下降趋势,而CO2补偿点(VCCP)和CO2饱和点(VCSP)均呈上升的趋势。100%与40%处理相比,两者除暗呼吸速率(Rn)未达到显著差异(P>0.05)外,其余参数差异的均达到显著水平(P<0.05)。形态学指标的结果也显示,在土壤含水量相对较高的环境下(100%和80%),伯乐树幼苗的株高、冠幅、分枝数和生物量等均较大(P<0.05),表现出良好的生长态势。综合本次实验结果表明,较高的土壤相对含水量(>60%)有利于伯乐树的生长发育。建议在进行伯乐树幼苗繁育时,应适当的增加土壤含水量。In order to investigate Bretschneidera sinensis seedlings＇ response of photosynthetic physiology to different soil water contents, the morphological indicators and related photosynthetic parameters of the seedlings under conditions of different soil water contents were compared and studied. The results show that when the soil water relative content was greater than 40%, the transpiration rate（Tr） of the different treatments was no significant difference （P 〉 0.05）; With soil water relative content 40%, the water use efficiency （RwuE） and stomatal limitation value （VLs） were higher（P 〈 0.05）; As the soil water contents decreasing, the maximum photosynthetic rate （Pmax）, light compensation point （VLcP）, light saturation point （VLsP）, maximum carboxylation rate （Amax） and carboxylation rate （Rcu） were all decreased on the whole, while the CO2 compensation point （VccP） and CO2 saturation point （VcsP） increased with soil water decreasing; Compared the treatments with soil water relative content 100% and 40%, the differences of these photosynthetic parameters were all significant （P 〈 0.05） except the mitochondrial respiration （Rn） （P 〉 0.05）. The morphological indicators also indicate that the plant height, crown width, branch number and biomass maintained at the highest levels under relative high soil water contents （26.90%±1.41 and 21.52 %± 1.10）, showing good growth momentum. The findings reply that higher soil relative water content （ 〉 60%） will be in favor of the growth of B.sinensis seedlings.

关 键 词：伯乐树 幼苗 土壤含水量 形态 光合 

分 类 号：S714.5[农业科学—林学] Q949.748.6[生物学—植物学]