干旱胁迫对茄子幼苗生长及生理特性的影响

Effects of Drought Stress on Growth and Physiological Characteristics of Eggplant Seedlings

本试验以茄子为材料,研究干旱胁迫对茄子幼苗生长及生理特性的影响。设置4个干旱胁迫处理梯度,其土壤含水量分别为对照(70%~80%)、轻度胁迫(50%~60%)、中度胁迫(40%~50%)和重度胁迫(30%~40%)。结果显示:随干旱胁迫强度的增加,茄子幼苗的株高、茎粗、干重、壮苗指数、相对生长量和叶绿素、可溶性蛋白含量及CAT活性均逐渐降低,且均低于对照,在2 d与对照相比下降较小,但随干旱胁迫时间延长急剧下降,且干旱强度越大,下降越明显,其中叶绿素、可溶性蛋白含量及CAT活性与壮苗指数、相对生长量呈极显著正相关;MDA、脯氨酸含量及SOD、POD活性均逐渐增加,且均高于对照,其中MDA含量在2 d时急剧增加,但随后下降,而脯氨酸含量及SOD、POD活性在2 d、4 d时增加较小,但随干旱胁迫时间延长急剧增加,且干旱强度越大,增加越高。研究表明,在一定强度的干旱胁迫下,茄子幼苗的地上部生长受到抑制,在干旱胁迫前期细胞膜受到伤害较大,且随着干旱胁迫时间的延长叶绿素合成受到抑制越明显,但能通过自身的抗氧化酶系统和渗透调节物质来提高对干旱胁迫的适应能力。

To study the effect of drought stress on the growth and physiological characteristics of eggplant seedlings.Four treatment gradients of drought stress were set up,and the water content of the soil were control(70%-80%),mild stress(50%-60%),moderate stress(40%-50%)and severe stress(30%-40%),respectively.The results showed that with the increased of drought stress intensity,the plant height,stem diameter,dry weight,strong seedling index,relative growth,the contents of chlorophyll and soluble protein and CAT activity of eggplant seedlings decreased gradually,and they were all lower than CK.And the decrease was smaller compared with CK in the second day,but decreased sharply with the extension of drought stress time and the greater the drought intensity.In which the contents of chlorophyll and soluble protein and CAT activity were significantly positively correlated with the strong seedling index and relative growth.The contents of MDA and proline and the activities of SOD and POD increased gradually,and they were all higher than CK.The content of MDA increased sharply in the second day,but then decreased,while the content of proline and the activities of SOD and POD increased slightly in the second and fourth days,but increased sharply with the extension of drought stress time and the greater the drought intensity.The results showed that under the certain drought stress,the growth of eggplant seedlings is inhibited,the cell membrane is damaged greatly in the early stage of drought stress,and the content of chlorophyll is inhibited more obviously with the extension of drought stress time,but the adaptability of eggplant seedlings to drought stress could be improved through its antioxidant enzyme system and osmotic regulation substances.