干旱胁迫下沙芥幼苗叶片光合特性和叶绿素荧光参数的变化  

Changes of photosynthetic pharacteristics and chlorophyll fluorescence parameters of Pugionium cornutum(L.) Gaertn seedlings leaf under drought stress

作　　者：王萍[1] 张希吏 石磊[1] 

机构地区：[1]内蒙古农业大学农学院/内蒙古自治区野生特有蔬菜种质资源与种质创新重点实验室,内蒙古呼和浩特010019

出　　处：《干旱地区农业研究》2017年第3期159-163,共5页Agricultural Research in the Arid Areas

基　　金：国家自然科学基金项目(31260475;30960236;30560088);内蒙古农业大学创新(培育)团队(NDPYTD2013-3)

摘　　要：以一年生沙芥幼苗的叶片为实验材料,采用盆栽实验的方法,将土壤含水量设置为正常浇水为对照(70%~75%WHC,CK),轻度干旱胁迫(55%~60%WHC,LD),中度(40%~45%WHC,MD),重度(25%~30%WHC,VD)四个处理,用Li-6400光合仪和叶绿素荧光仪FMS2(Hansatech,UK),研究干旱胁迫下沙芥光合参数、荧光参数的变化规律,探讨干旱胁迫对沙芥叶片光合生理指标的影响,旨在揭示沙芥对干旱胁迫的响应机制,为阐明沙芥的耐旱性提供理论依据。结果表明:(1)随着干旱胁迫程度的加剧,沙芥叶片叶绿素a,b含量在各干旱胁迫处理下,比对照下降了1.30%~7.04%和19.47%~42.37%,类胡萝卜素含量下降了2.06%~9.88%。叶绿素a/b上升了33.49%~74.27%,Car/Chl上升了1.33%~15.73%。(2)随着干旱胁迫的加剧,沙芥叶片的净光合速率、蒸腾速率、水分利用率呈现下降的趋势,胞间CO2浓度先下降后上升,气孔限制值不断下降。这表明轻度干旱胁迫下气孔限制是影响沙芥幼苗叶片Pn下降的主要因素;中度和重度干旱胁迫下,非气孔限制是沙芥幼苗叶片Pn下降的主要因素。(3)干旱胁迫下,沙芥叶绿素荧光参数Fv/Fm、Fv/Fo、ΦPSⅡ,q P和ETR均呈下降趋势,q N在干旱胁迫下不断上升。With the help of the method of a pot-cultivation experiment and the reference of different soil content with 70% -75%WHC（CI〇, 55% -60%WHC（LD）,4 0 % -4 5 %WHC（MD）,2 5 % -3 0 %WHC（VD） and with FMS-2 and Li - 6400 photosynthetic apparatus, choosing seedling leaves of Pugionium cornutum（h . ） Gaertn as the experimen-tal materials, this paper studies the change laws of hlorophyll fluorescence parameters of Pugionium cornutum （ L .） Gaertn under the drought stress, and the effects of drought stress on its photosynthetic index. The purpose of this paper is to reveal the mechanism of Pugionium cornutum （ L . ） Gaertn dealing with the drought stress, and to illustrate its drought resistance. The results showed that： （1） With intensifying drought stress, by contrast, the content of Pugionium cornu- leaf chlorophyll a,chlorophyll b in c〇7 m^um（L .） Gaertn decreased by 1.30% -7.04% and 19.47% -42. 37% respectively, carotene content by 2.06% -9.88% ; the value of chlorophyll a/b and Car/Chi increased by 33. 49% -74.27% and 1.33% -15.73% respectively. （2） With intensifying the drought stress,there were distinct de-crease trends of the net photosynthetic rate（,transpiration rate （ 7 V） ,stomatal conductance（ Gs） and water use effi- ciency（WUE） of P , cornutum（L . ） Gaertn leaves, and the carbon dioxide concentration decrease at first and then in-crease and the stomatal limitation（ ） decrease, which showed that Pn decrease of P . cornutum（h . ） Gaertn leaves un-der light stress was mainly induced by stomatal factors, and Pn decrease under moderate and severe stress was mainly in-duced by non-stomatal factors. （3） Under drought stress, there were decrease trends of Fv/ Fin, Fv/F o,ФPS Ⅱ ,qP, ETR of Pugionium cornutum （L . ） Gaertn leaf, and increase trends of qN.

关 键 词：沙芥幼苗 干旱胁迫 光合参数 叶绿素荧光参数 

分 类 号：S637[农业科学—蔬菜学]