砧木对盐处理下‘丰水’梨幼树光合特性的影响

 用CIRAS-1便携式光合作用测定系统研究不同盐浓度处理下，分别以‘豆梨’、‘杜梨’作砧木的‘丰水’梨幼树叶片光合作用。结果表明：(1)不同砧木对盐处理下的丰水梨叶片光合作用反应有显著影响；(2)在相同条件下杜梨上的丰水较豆梨上的丰水有更高的净光合率(Pn)、气孔导度(Gs )、蒸腾速率(Tr)和羧化效率(CE)，而在高浓度盐处理下，前者较后者有较低的细胞间隙CO₂浓度(Ci)。(3)低盐胁迫对梨叶片光合作用的抑制，初期主要表现为气孔性限制，而在高盐处理和低盐处理后期主要表现为非气孔性限制；(4)不同砧木对梨叶片光合作用的影响在高盐处理后期差异不明显。

Effects of Rootstocks on Photosynthetic Properties of Young''''Hosui''''Pear Trees under Salinity

The effect of two pear rootstocks'Calleryana'and'Betulaefolia'on photosynthetic properties of young'Hosui'under salinity was measured by portable photosynthesis systems CIRAS-1.The results showed that:(1) There are obvious discrepancy between Pyrus betulaefolia and P.calleryana effect on the photosynthetic properties of Hosui blade;(2)Pn,Gs,Tr,and CE were higher in Hosui combined with P.betulaefolia (H-B)than in Hosui combined with P.calleryana(H-C)under the same conditions,H-C with higher Ci than H-B under high salinity.(3)Photosynthesis of pear blade was inhibited by salinity most cause for stomatal limitation under low salinity at early time,and most cause for nonstomatal limitation under high salinity and low salinity at anaphase; (4)In anaphase of treatment,the discrepancy between P.betulaefolia and P.calleryana effect on photosynthetic properties was diminished under severe salinity.