不同苗龄无翼坡垒生长和光合生理特性差异性研究

Study of growth and photosynthetic physiological characteristics variations for different ages of Hopea exalata seedling

栽植3年生、4年生和8年生3种苗龄无翼坡垒(Hopea exalata),比较研究其生长和光合生理特性的差异性,为该物种的迁地保护提供有效途径。结果表明,不同苗龄无翼坡垒苗木净生长量存在一定差异。随着苗龄的增加,无翼坡垒苗高和冠幅净生长量呈升高趋势,苗高净生长量以8年生最大,地径净生长量以4年生最大。光合特性和叶绿素荧光参数结果显示,叶片光合速率(Pn)、蒸腾速率(Tr)和胞间二氧化碳浓度(Ci)均以8年生无翼坡垒最大;随着无翼坡垒苗龄的增加,最初荧光F0、最大荧光Fm、变动荧光Fv和最大光能转换效率Fv/Fm均呈小幅度的升高趋势。基于研究结果提出,栽培地高温是影响无翼坡垒生长和光合生理的主要环境因子,适当创造栽培地环境,以适应无翼坡垒生长和发育的需要。

In this study,3-years-old,4-years-old and 8-years-old of Hopee exalata were selected as experimental materials to growth and photosynthetic physiological characteristics,which it could provide an effective way for the exsitu conservation of the species.The results showed that there was difference in the net growth of seedlings of different ages.With the increase of seedling age,showed a trend of increase,the net height and the crown showed a trend of increase.The net height was higher in 8-years-old seedlings,and the net growth of ground diameter was the higher in 4-years-olds.The photosynthesis characteristics and chlorophyll fluorescence parameters showed that photosynthetic rate(Pn),transpiration rate(Tr)and intercellular carbon dioxide concentration(Ci)were the largest in the 8-years-old seedling.With the increase of seedling age,the minimum initial fluorescence F0,the maximum fluorescence Fm,the variable fluorescence Fv,and light energy capture efficiency Fv/Fm showed an inconsistent variation trend.Based on the research results,the high temperature of cultivated land was the main environmental factor affecting the growth and photosynthetic physiology of H.exalata,which the environment of cultivated land proposed to facilitate sustainable for the growth and development of wingless barriers H.exalata.