华北农学报Issue(z1)：155-160,6.
桑树幼苗叶片叶绿素荧光特性对不同 pH 值碱性盐胁迫的响应
Responses of Chlorophyll Fluorescence Characteristics in Leaves of Mulberry Seedlings to Alkaline Salt Stress with Different pH Value
摘要
Abstract
In this paper ,taking mulberry seedlings as test material ,the effects of diffierent concentration alka-line salt(Na2CO3)stress(Density of concentration was 100 mmol/L and value of pH were 7.0,8.0,9.0 and 10.0) on chlorophyll content , relative water content , cell membrane permeability changes and Chlorophyll fluorescence characteristics in mulberry seedlings were investigated .The results showd that under the alkaline salt stress with pH values in 7 .0-9 .0 ,chlorophyll content and relative water content were reduced smaller ,malondialdehyde contents were no apparent increased and peroxidation of membrane were no occurred significantly .Meanwhile ,the inhibitions of PSⅡphysiological function were also not being obvious in leaves of mulberry seedlings .However,the leaves of mulberry seedlings could protect normal physiological function of PSⅡreaction centers by non-radiative energy dis-sipation mechanism which was xanthophyll-regulated thermal energy dissipation as the main , thus leaves of PSⅡcould guarantee the normal capacity of electronic transport and utilization of solar energy .Namely,the PSⅡin Leav-es of Mulberry seedlings had an alkaline salt-tolerance ability in some degree .But when the pH up to 10.0,mem-brane systems in leaves of Mulberry seedlings were damaged ,leaves water loss were seriously ,and Per unit area of chlorophyll content were appreciably reduced which reducing of chlorophyll a content particularly clear .Further-more,photosynthetic electron transports were hindered in leaves of Mulberry seedlings , and the absolute energy could used in photosynthetic electron transports imcompletely .The non-radiative energy dissipation mechanisms by xanthophyll cycle were inhibited simultaneously , which resulted in an accumulated excess light energy ( 1 -q P )/NPQ in the leaves.Then closure and deactivation of PSⅡreaction centers accelerated rapidly ,which might be a way to alleviate the pressure on PSⅡreaction centers ,but at the same time decreased the capacity of solar energy utili-zation in particular to high light intensity utilization in the leaves of Mulberry seedlings .关键词
桑树/碱性盐胁迫/pH值/叶绿素荧光Key words
Mulberry/Alkali salt stress/pH value/Chlorophyll fluorescence分类
农业科技引用本文复制引用
张会慧,张秀丽,胡彦波,李鑫,田野,王娟,孙广玉..桑树幼苗叶片叶绿素荧光特性对不同 pH 值碱性盐胁迫的响应[J].华北农学报,2013,(z1):155-160,6.基金项目
国家科技支撑项目（2011BAD08B02-3）；国家自然科学基金项目（31070307；30771746）；黑龙江省自然科学基金重点项目 （）
