作 者 ：任 鹏1,赵宝平1*,刘瑞芳2,杜 嵘1,王 欢1,刘景辉1,王玉芬3

期 刊 ：西北植物学报 2014年 10期 页码：2049~2055

关键词：燕麦；水分胁迫；穗颖；渗透调节；抗氧化能力；

Keywords:oats, water stress, glume, osmotic adjustment, antioxidation ability,

摘 要 ：以抗旱性不同的燕麦品种‘蒙燕1号’(抗旱性强)和‘坝莜3号’(水分敏感)为试验材料,采用盆栽方式研究了抽穗期和灌浆期水分胁迫对燕麦穗颖渗透调节和抗氧化能力的影响。结果表明:(1)水分胁迫处理均显著促进了不同抗旱性品种穗颖渗透调节物质(游离脯氨酸和可溶性蛋白)含量增加,并以抗旱品种累积水平高于水敏感品种,且两种渗透调节物质对抽穗期胁迫的反应比灌浆期胁迫更敏感。(2)两时期的水分胁迫处理均能降低不同抗旱性品种穗颖SOD和POD活性,抗旱品种的保护酶活性要高于水敏感品种,抗旱品种的SOD活性降低幅度明显低于水敏感品种,而POD活性降低幅度在两品种间差异不明显。(3)水分胁迫导致2个品种穗颖丙二醛(MDA)含量和相对电导率显著增加,细胞膜结构受到严重伤害,且水敏感品种受害程度大于抗旱品种。(4)水分胁迫使2个品种单株籽粒产量下降,且在中度胁迫和重度胁迫下,抗旱品种的减产幅度要低于同期水敏感品种;水分胁迫下,水敏感品种‘坝莜3号’减产4.54%～30.29%,抗旱品种‘蒙燕1号’减产6.69%～23.54%。可见,抗旱性强的燕麦品种在受到水分胁迫的条件下能通过增强穗颖渗透调节和抗膜质过氧化能力、减弱穗颖细胞质膜损伤程度来适应干旱胁迫,最大限度减少水分胁迫对穗颖的伤害,有利于稳产。

Abstract:In order to explore the adaptability characteristics of oats glume under water deficit,this paper used different drought resistance oat varieties ‘Bayou 3’(water sensitive) and ‘Mengyan 1’(drought-resistant) as test materials,to study osmotic regulation and anti-oxidation ability of oat glumes at heading stage and filling stage under water stress by pot experiment.The results showed that:(1)Water stress treatments could significantly promote the content of osmolytes among different drought-resistance varieties.The accumulation level of drought-resistant variety was higher than that of water sensitive one,and the reaction of two osmolytes to stress was more sensitive at heading stage than that of filling stage.(2)Water stress treatments could reduce the superoxide dismutase (SOD) and peroxidase(POD) activities of glume among different drought-resistance varieties in both heading and filling stage.The protective enzyme activities of drought-resistant variety were higher than that of water sensitive variety.The SOD activity reduction rate of drought-resistant variety was significantly lower than that of water sensitive variety,while the POD activity decreased with no obvious difference between the two varieties.(3)Water stress led to methane dicarboxylic aldehyde (MDA) content and the relative electrical conductivity increased significantly,and the change of water sensitive variety was greater than that of drought-resistant variety.(4)Water stress decreased the grain yield per plant.The yield reduction rate of drought-resistant variety was lower than that of water sensitive variety under moderate stress and severe stress in the same period.Under water stress,the reduction of ‘Bayou 3’ was from 4.54% to 30.29%,while ‘Mengyan 1’ was from 6.69% to 23.54%.Therefore,the drought resistance of oat varieties to adapt to water stress by strengthening the osmotic adjustment and antioxidation ability reduced the golem cell membrane damage,which helps to minimize the damage of water stress,conducive to stable yield.