过表达IbMYB1基因甘薯增强了对土壤干旱胁迫的抗性

Overexpression of IbMYB1 Gene Enhanced Tolerance to Soil Drought Stress in Sweet Potato

以超表达甘薯MYB1基因(Ib MYB1)的转基因甘薯(TS)以及未转基因甘薯(NT)为实验材料,在盆栽条件下对成活苗进行干旱胁迫处理,研究转基因与未转基因甘薯在干旱胁迫后,膜脂过氧化及抗氧化系统中主要指标的变化情况。结果表明,在干旱胁迫条件下,转基因甘薯花青素含量显著增加,薯块中花青素含量最高为对照的7倍;转基因和未转基因甘薯在土壤干旱条件下叶绿素含量降低;超氧阴离子(O2?ˉ)和丙二醛(MDA)含量增加,转基因甘薯的增加幅度低于未转基因甘薯;转基因甘薯超氧化物歧化酶(SOD)、过氧化氢酶(CAT)和抗坏血酸过氧化物酶(APX)活性都高于未转基因甘薯。这些结果表明超表达Ib MYB1基因可以降低甘薯在干旱胁迫条件下受损害的程度。

Transgenic sweet potato（TS） overexpressing Ib MYB1 and non-transgenic（NT） were employed as experimental material, and chose survival seedlings in pots with drought stress condition. Response of lipid peroxidation and antioxidative system during drought stress in TS and NT were investigated. The results indicated that anthocyanin contents of TS increased obviously, the biggest anthocynin content in storage roots of TS was seven times to control. Chlorophyll contents in TS and NT plants decreased during drought stress, while, O2ˉ？ and malondialdehyde（MDA） contents in TS and NT were increased, and the increase rate of TS was signifi-cantly lower than NT. The activities of SOD, CAT and APX in TS were obviously higher than those in NT plants. It was concluded that overexpression of Ib MYB1 gene could reduce damage degree of sweet potato under the condition of drought stress.