【摘要】 将‘燕红’桃在果核硬化期和果实最后迅速生长期留果对照和去果比较,去果(库)后叶片 (源)净光合速率(Pn)、气孔导度(Gs)和蒸腾速率(E)降低,叶片温度(Tleaf)升高,对细胞间隙 CO2浓度(Ci)无显著影响。去果对Pn、Gs、E和Tleaf的影响主要发生在9:00～16:00之间,且在中午前 后一段时间里影响最显著。研究叶片Pn与Gs之间的关系表明,当Gs值小于60mmol·m-2·s-1时,二者 呈极显著正相关。此外,留果对照和去果处理间叶片Pn差值与Tleaf差值呈显著或极显著的正相关。去果降 低库力,减少叶片Gs并导致叶片温度的增加可能是源叶Pn降低的关键因素。更多还原

【Abstract】 The effect of defruiting on source leaf net photosynthesis(Pn) and related physiological response was investigated on‘Yanhong’peach trees(Prunus persica) during the fruit stone hardening and final fruit rapid growth stage. The results showed that Pn, stomatal conductance(Gs) and transpiration(E) in source leaves decreased significantly while leaf temperature (T leaf) increased from defruiting trees as compared with those from fruiting ones. There was, however, no significant difference of substomatal CO 2(Ci) between fruiting and defruiting treatments. The effect of reducing the sink activity by defruiting treatment on Pn, Gs, E and T leaf appeared during 9:00 and 16:00. The relationship between Pn and Gs was significantly positive only when Gs was less than 60 mmol·m -2·s -1. The difference of Pn between fruiting and defruiting increased with the increasing difference of T leaf between defruiting and fruiting treatments. It is suggested that an increasing T leaf, resulting from the stomatal closure, may be a key factor which leads the decrease of leaf Pn in reducing the sink activity in fruit trees.更多还原