摘要
以两个变种甜瓜幼苗为材料,在人工控制条件下研究了NaCl胁迫对甜瓜叶片气体交换和叶绿素荧光特性的影响。结果表明,盐胁迫降低了甜瓜叶片光合色素含量、净光合速率、蒸腾速率、气孔导度和PSⅡ最大光化学效率、PSⅡ潜在活性、PSⅡ电子传递量子效率和光化学猝灭系数,使非光化学猝灭系数升高。在≤50 mmol.L-1NaCl胁迫下,甜瓜叶片光合速率降低主要由气孔因素引起,而在NaCl浓度≥100 mmol.L-1条件下则以非气孔限制因素为主。
Muskmelon seedlings, cv. Huanghemi and Baishami, were employed to study the effect of NaCl stress on photosynthesis, chlorophyll contents and chlorophyll fluorescence parameters. The results indicated that net photosynthetic rate （ Pn ）, transpiration rate （Tr）, stomatal conductance （Gs）, maximum photochemical efficiency of PS Ⅱ （Fv/Fm）, potential activity of PS I1 （Fv/Fo）, quantum efficiency of non-cyclic electron transport of PS Ⅱ （ФPS Ⅱ ） and photochemical quenching（qP） decreased, while non-photochemical quenching（qN） increased under NaCl stress, especially under high concentrations in both varieties. When NaCl concentration was 450 mmol. L^-1, intercellular CO2 concentration （Ci） decreased, while stom- atal limitation value （Ls） increased. In contrast, Ci increased but L8 decreased when NaCl concentration was ≥100 mmol. L^-1. The results indicated that photosynthesis of muskmelon was limited by stomatal factor under slight NaCl stress, but mainly by non-stomatal factors under severe NaCl stress.
出处
《中国沙漠》
CSCD
北大核心
2009年第6期1129-1133,共5页
Journal of Desert Research
基金
国家科技支撑项目(2007BAD52B01)资助
关键词
甜瓜
盐胁迫
光合作用
叶绿素荧光参数
kmelon
NaCl stress
photosynthesis
chlorophyll fluorescence parameters
