水淹条件下狗牙根对镉胁迫的生理生化响应  

Bermudagrass Under Water-flooding: Physiological and Biochemical Response to Cadmium Stress

作　　者：董方旭 谭淑端[1] 杨雨婷[1] 陈镔 

机构地区：[1]湖南农业大学生物科学技术学院,长沙410128

出　　处：《中国农学通报》2017年第33期120-126,共7页Chinese Agricultural Science Bulletin

基　　金：国家自然科学基金"水淹抵消镉对狗牙根毒害作用的机理"(31400339);中国博士后科学基金"狗牙根对水淹和镉同时胁迫的响应及耐性机理"(2013M542113);湖南省教育厅优秀青年科学基金"不同栽培模式对稻田温室气体排放的影响及机理"(15B113)

摘　　要：为了研究狗牙根分别经受水淹、镉胁迫和同时经受水淹和镉胁迫的生理生化响应。以野生狗牙根为试验材料,采取模拟盆栽的试验方法,设置8个不同处理。结果表明:水淹在一定程度上能促进狗牙根茎、叶的生长、抗氧化酶活性的升高以及对Cd^(2+)的吸收,同时也会抑制狗牙根根系的生长以及叶绿素的合成;镉胁迫下随着浓度的升高会使得狗牙根膜脂过氧化程度加剧,同时也会刺激其抗氧化酶活性增加来减少逆境所造成的伤害,并且POD、SOD、CAT 3种酶活在不同Cd^(2+)浓度下表达不同;狗牙根不同部位吸收镉的能力表现为:叶>根>茎,且对镉的耐受阈值达到了150 mg/L,其富集系数大于1、转运系数大于0.5。在镉胁迫的伤害阈值内狗牙根可以正常生长,其可作为同时遭受水淹和重金属污染地区植被恢复的优良物种。The paper aims to study the physiological and biochemical responses of Bermudagrass under water-flooding, cadmium stress and the above two conditions at the same time. With wild Bermudagrass as the studymaterial, the authors adopted the pot simulation method and designed 8 different treatments. The resultsshowed that： to some extent, water-flooding promoted the growth of rhizomes and leaves of Bermudagrass andthe increase of the anti-oxidant enzymes activity as well as the absorption of Cd2 ＋, meanwhile, it alsosuppressed the growth of roots and synthesis of chlorophyll; with increasing cadmium concentration, it couldaggravate the degree of the membrane lipid peroxidation and stimulate the increase of the anti-oxidantenzymes activity in order to reduce the harm caused by adversity, and 3 enzymes（POD, SOD and CAT）displayed different expressions under different Cd2 ＋concentrations; the cadmium absorption abilities ofdifferent parts of Bermudagrass were leavesrootsstems, and Bermudagrass had a cadmium tolerancethreshold of 150 mg/L with an enrichment coefficient greater than 1 and transport coefficient greater than 0.5.Bermudagrass can grow normally within the threshold of cadmium stress-induced harm and is considered as agood species for revegetation in the regions suffered from both water-flooding and heavy metal pollution.

关 键 词：水淹 狗牙根 镉胁迫 抗氧化酶 

分 类 号：Q149[生物学—生态学]