摘要
以当地辣椒(Capsicum annuum L.)主栽品种"陇椒5号"和"七寸红"为试材,研究自毒作用下不同浓度外源谷胱甘肽(GSH)对辣椒幼苗叶绿素含量、光合参数和叶绿素荧光参数的影响,以探讨GSH对辣椒自毒作用的缓解效果和生理作用机制。结果表明:单一叶浸提液处理(CK2)后,2个品种辣椒叶片的叶绿素含量、净光合速率(Pn)、气孔导度(Gs)、蒸腾速率(Tr)、PSII最大光化学效率(Fv/Fm)、PSII有效光能转化效率(Fv'/Fm')和实际光化学效率(ФPSII)均较清水处理(CK1)降低,初始荧光(Fo)升高,胞间CO2浓度(Ci)则先升后降。说明辣椒叶浸提液引起的自毒作用导致光合作用的下降主要是由于非气孔因素引起的。含有不同浓度GSH的叶浸提液处理后,叶绿素含量、Pn、Gs、Tr、Fv/Fm、Fv'/Fm'和ФPSII与单一辣椒叶浸提液处理相比均有一定程度的回升,Ci和Fo均较叶浸提液处理的降低。说明外源GSH能够提高自毒作用下辣椒幼苗叶片CO2的利用率,降低非气孔因素的伤害,进而缓解自毒物质对辣椒幼苗的毒害。研究表明,适合缓解陇椒5号和七寸红自毒作用的GSH浓度分别为50和30mg.L-1。
Effects of Glutathione （GSH） with different concentrations on chlorophyll content （ Chl）, photosynthetic parameters and chlorophyll fluorescence parameters in leaves of pepper were investigated, using pepper varieties of ＇ Longjiao No. 5＇ and ＇ Qicunhong＇ under autotoxicity. Results showed that Chl, net photosynthetic rate（Pn）, stomatal conductance（Gs） and transpiration rate （Tr） declined sharply, but intercellular CO2 concentration （Ci） increased significantly after treated with leaf aqueous extracts of 50g·L^-1. The contents of Chl, Pn, Gs and Tr increased, while Ci increased at first then decreased rapidly after treated with exogenous GSH, which suggested that Pn reduction was mainly due to non-stomatal factors. Maximum photochemical efficiency of PSII （Fv/Fm） , maximal efficiency at open centers in the presence of NPQ （Fv＇/Fm＇） and actual quantum yield of PS I1 electron transport （φPSII） declined, but origin fluorescence （Fo） increased under autotoxicity. The peppers treated with GSH had higher Fv/Fm, Fv＇/Fm＇ andφPSII, while Fo decreased significantly under different concentrations of GSH compared with those treated by water or leach liquor only. It was illustrated that exogenous GSH regulated the changes of leaf gas exchange and chlorophyll fluorescence parameters, especially, by preventing the accumulation of CO2 in the leaves which was associated with an improvement in the non-stomatal factors, then alleviated the barrier of continuous pepper cropping caused byautotoxicity. There were certain alleviate effects of exogenous among the glutathione concentrations used, 50 and 30 mg· L^-1 and ＇Qicunhong＇ , respectively. GSH on the two varieties of peppers under autotoxicity, i were the optimum concentrations for ＇ Longjiao No. 5＇and ＇ Qicunhong＇ , respectively.
出处
《核农学报》
CAS
CSCD
北大核心
2012年第2期396-402,共7页
Journal of Nuclear Agricultural Sciences
基金
国家科技支撑计划(2007BAD89B17)
国家星火计划(2010GA860012)
甘肃省科技重大专项计划(1002NKDA038)
关键词
辣椒
叶浸提液
谷胱甘肽
光合参数
荧光参数
pepper
leaf aqueous extracts
GSH
photosynthetic parameters
chlorophyll fluorescence
