干旱胁迫时间对6份饲用燕麦种质萌发期生理指标的影响

Effects of Drought Stress Duration on Physiological Indexes of 6 Oat Germplasms at Germination Stage

为研究干旱胁迫时间对不同燕麦(Avena sativa L.)材料萌发期生理生化的影响,采用15%聚乙二醇对6份饲用燕麦种子分别进行干旱胁迫0,24,48,72和96 h后测定生理生化指标。结果发现:胁迫时间对各指标的影响不尽相同,丙二醛(Malondialdehyde,MDA)和可溶性糖(Soluble sugar,SS)含量均随胁迫时间延长而增加,72 h时达到峰值;可溶性蛋白(Soluble protein,SP)和脯氨酸(Proline,Pro)含量的变化因供试材料不同而异;超氧化物歧化酶(Superoxide dismutase,SOD)和过氧化物酶(Peroxidase,POD)活性多在24 h和48 h时达到最大;过氧化氢酶(Catalase,CAT)活性在24 h和72 h时达到峰值;各抗旱性指标间具有较强的相关性,相关系数最高达0.893。渗透调节物质、膜脂过氧化特性、抗氧化酶活性可作为燕麦萌发期响应干旱胁迫的主要生理指标;6份供试材料中,‘DA92-2F4’和‘蒙燕1号’耐旱性较强,‘甜燕麦’最弱。

To study the effects of drought stress duration on the physiology and biochemistry of different Avena sativa materials during germination,six forage oat seeds were subjected to drought stress with 15%PEG.The physiological and biochemical indexes were measured after 0,24,48,72,and 96 hours of stress.The results showed that the effects of stress duration on each index were different.The contents of malondialdehyde(MDA)and soluble sugar(SS)increased with the extension of stress time,and reached the peak at 72 h;The contents of soluble protein(SP)and proline(pro)varied with different materials;The activities of superoxide dismutase(SOD)and peroxidase(POD)reached the maximum at 24 h and 48 h;Catalase(CAT)activity peaked at 24 h and 72 h;The correlation coefficient was as high as 0.893.Osmotic regulators,membrane lipid peroxidation,and antioxidant enzyme activity could be used as the main physiological indexes in response to drought stress during oat germination.Among 6 materials,‘DA92-2F4’and‘Mengyan No.1’had strong drought tolerance,and‘Sweet oat’was the weakest.