4种砧木嫁接的红阳猕猴桃光合特性比较

【目的】比较不同砧木嫁接的红阳猕猴桃光合特性,为筛选更适合红阳猕猴桃嫁接的砧木提供参考。【方法】用Li-6400光合测定系统分别测定阔叶砧木（A.latifolia）、桂林砧木（A.guilinensis）、长果砧木（A.longicarpa）和中华砧木（A.chinensis）嫁接的两年生红阳猕猴桃成熟叶片的光响应曲线和光合日变化特征,采用非直角双曲线方程拟合光响应曲线及各光合参数。【结果】4种砧木嫁接的红阳猕猴桃最大净光合速率（Pmax）在17.6853-24.8340μmol/m^2·s变化,表观量子率（AQY）为0.0465-0.0538,光饱和点（LSP）为433.60-494.79μmol/m^2·s,光补偿点（LCP）为33.19-61.79μmol/m^2·s;长果砧木嫁接的红阳猕猴桃光合性能最好,其Pmax、AQY和LSP均最高。红阳猕猴桃的净光合速率（Pn）日变化曲线为双峰型,光合最高峰出现在上午9：30左右,在13：00-14：00,因高温和空气湿度下降引起气孔关闭,发生光合‘午休’现象;长果砧木嫁接的红阳猕猴桃净光合速率（Pn）、水分利用效率（WUE）、光能利用效率（LUE）和羧化效率（CE）均最高。【结论】从光合效率角度评价,选择长果砧木作为红阳猕猴桃的嫁接砧木效果较佳。

Photosynthetic characteristic comparison of ‘Hongyang’ kiwifruit grafted with four different rootstocks

【 Objective 】 Photosynthetic characteristic comparison of ‘ Hongyang ＇ kiwifruit grafted with four different rootstocks was conducted to provide references for selecting suitable rootstock for ‘Hongyang ＇ kiwifruit. 【Method 】The light response curve and diurnal variation of photosynthetic physiological parameters of two-year-old ‘Hongyang ＇ kiwifruit grafted with four different rootstocks（Actinidia latifolia, A. guilinensis, A. longicarpa and A. chinensis） were measured by using Li-6400 portable photosynthesis system. The non-rectangular hyperbolic model was adopted to fit the light response curve. 【 Result 】 The results of light response curve measurement indicated that the photosynthetic characteristics of ‘Hongyang ＇ kiwifruit grafted with four rootstocks showed obvious variations. The variations of maxi-mum net photosynthetic rate（Pmax）, apparent photosynthetic quantum yield（AQY）, light saturation point（LSP） and light compensation point（ LCP） were 17. 6853- 24. 8340 μmol / m2·s, 0. 0465- 0. 0538 μmol / m2·s, 433. 60- 494. 79μmol/m^2·s and 33.19-61.79 μmol/m^2·s, respectively. The Pmax, AQY and LSP in ‘Hongyang ＇ kiwifruit grated with rootstock of Actinidia longicarpa were all the highest. The results of diurnal variation of photosynthesis measurement showed that the diurnal variation of net photosynthetic rate（Pn） in ‘Hongyang ＇ kiwifruit was a double-peak model,and the first photosynthetic peaked at about 9 ：30 a.m. The midday depression of photosynthesis appeared at 13 ：00-14 ：00, and it was because of the stomatal closure caused by high temperature and the decrease of air humidity. The Pn, water use efficiency（WUE）, light use efficiency（LUE） and carboxylation efficiency（CE） in ‘Hongyang ＇ kiwifruit grafted with rootstock of A. longicarpa were all the highest compared with those grafted with other three root-stocks. 【 Conclusion 】 Based on the performances of photosynthetic characteristics, A. longicarpa may be the