NaCl 胁迫对忍冬光合作用的影响

摘要

在水培条件下，采用 LI －6400便携式光合仪测定不同浓度 NaCl 溶液下忍冬扦插苗净光合速率（Pn）、光饱和点（LSP）、光补偿点（LCP）、暗呼吸速率（Rd）、最大净光合速率（Amax ）以及表观量子效率（AQE）等参数，研究忍冬扦插苗的光合参数对 NaCl 溶液的响应规律，探讨有利于忍冬扦插苗正常生长的适宜盐浓度。结果表明：低浓度 NaCl 胁迫（≤0．3％）对忍冬光合作用的影响较小，高浓度 NaCl 胁迫（≥0．5％）对其光合作用影响较大。当 NaCl 浓度为0．1％时，忍冬植株表观量子效率值最大，且光照有效利用区间最大（8～1379．5μmol·m －2·s －1），有利于忍冬扦插苗的正常生长。%Under hydroponic conditions,the photosynthetic parameters of Lonicera japonica Thunb.cut-tage seedlings,including net photosynthetic rate (Pn),light saturation point (LSP),light compensation point (LCP),dark respiration rate (Rd),maximum net photosynthetic rate(Amax )and apparent quantum efficiency (AQE),were determined using LI -6400 XT portable photosynthesis system under different salt concentra-tions.The response regularity of photosynthetic parameters to salt stress was studied to explore the suitable salt concentration for cuttage seedlings growth.The results showed that the effect of salt stress on photosynthesis of Lonicera japonica Thunb.was lower under less than or equal to 0.3% of NaCl concentration and higher under 0.5% or more of NaCl concentration.Under 0.1% of salt concentration,the AQE and light utilization range (8 ~1 379.5 μmol·m -2 ·s -1 )was the maximum,which was suitable for cuttage seedlings growth.