桃光合性能杂种优势的秋季日变化特征

摘要

“Diaozhibai”, “Xiahui 5” and their hybrid F1 seedlings were used to study diurnal variations in heterosis of photosynthetic performance in autumn. While the results showed positive heterosis of net photosynthetic rate (Pn) at noon and water use efficiency (WUE) for all day, that of transpiration rate (Tr) and stomatal conductance (Gs) was negative for all day. Positive correlations existed between Pn and Gs, and between Tr and Gs for hybrid F1, and the correlation between Pn and Tr was significantly positive at P＜0.05. The correlation between Pn and Tr, Gs and Pn as well as Gs and WUE was significant at P＜0.05 for parents. Grey correlation analysis indicated that atmospheric CO2 concentration (Ca) was the main factor influencing the rate of heterosis of Pn, Tr and WUE.%以桃品种"吊枝白"和"霞晖5号"及其杂交F1代种苗为试验材料,研究了桃在秋季的光合性能杂种优势日变化特征.结果表明:净光合速率(Pn)午间表现正向杂种优势,蒸腾速率(Tr)和气孔导度(Gs)金天基本表现负向杂种优势,而水分利用效率(WUE)则全天基本表现正向杂种优势.相关性分析表明,杂交F1代种苗的Pn与Tr、Pn与Gs、Tr与Gs均呈正相关,其中Pn与Tr之间相关性达显著水平(P<0.05);亲本的Pn与Tr之间呈显著正相关(P<0.05),Gs与Pn、WUE之间呈显著正相关(P<0.05).灰色关联度分析表明,影响Pn,Tr和WUE杂种优势率的主要因素均为大气CO2浓度(Ca).