---

作 者 ：杨凤娟¹;王秀峰¹;魏珉¹;苏秀荣²;闫童¹

期 刊 ：应用生态学报 2006年 17卷 03期 页码：403-407

关键词：黄瓜；

摘 要 ：

通过水培试验,探讨了不同NO₃^-浓度胁迫及恢复对黄瓜幼苗叶片叶绿素含量、叶绿素荧光参数及ATPase活性的影响.结果表明，胁迫7 d后，高浓度NO₃^-(168 mmol·L^-1)可极显著提高叶绿素a、叶绿素b、总叶绿素和类胡萝卜素含量,极显著提高初始荧光(F_o)、MgATPase和Ca-ATPase活性，而PSⅡ原初光能转化效率(F_v/F_m)、PSⅡ潜在活性(F_v/F_o)和PSⅡ光合电子传递量子效率(ΦPSⅡ)，却随NO₃^-浓度的增加而降低.恢复7 d后，所有处理叶绿素和类胡萝卜素含量均低于对照；初始荧光基本都恢复至对照水平;PSⅡ原初光能转化效率和PSⅡ光合电子传递量子效率在NO₃^-浓度低于126 mmol·L^-1时，基本恢复至对照水平，而高于这一水平时，仍显著低于对照;PSⅡ潜在活性在NO₃^-浓度为42和126 mmol·L^-1的处理基本达对照水平，其它处理仍极显著低于对照；Mg-ATPase和Ca-ATPase活性均出现先降低后升高的变化趋势.

Abstract:

With water culture,this paper studied the effects of NO₃^- stress and recovery on the chlorophyll contents,chlorophyll fluorescence parameters,and ATPase activities of cucumber seedling leaves.The results showed that under stress for 7 days,the chlorophyll a,chlorophyll b,total chlorophyll and carotenoid contents,intrinsic fluorescence (F_o),and MgATPase and Ca-ATPase activities were increased significantly when the NO₃^- concentration was high (168 mmol ·L^-1),while the intrinsic photochemical efficiency (F_v/F_m),potential activities (F_v/F_o) and quantum yield (ΦPSⅡ) of PSⅡ were decreased with increasing NO₃^- concentration.After recovery for 7 days,the chlorophyll and carotenoid contents of all treatments with NO₃^- were lower than CK,while the intrinsic fluorescence,intrinsic photochemical efficiency and quantum yield of PSⅡ were similar to CK when the NO₃^- concentration was ≤ 84 mmol·L^-1,and the F_v/F_m and ΦPSⅡ were significantly lower than CK when the NO₃^- concentration was>84 mmol·L^-1.The potential activity of PSⅡ was similar to CK when the NO₃^- concentration was 42 and 126 mmol·L^-1,but significantly lower than CK in other treatments.The activities of Mg-ATPase and Ca-ATPase were decreased firstly but increased then when the NO₃^- concentration was>84 mmol·L^-1.

---