YHem1基因转化香蕉提高植株抗冷性研究

YHem1 Transformation into Banana to Improve Its Cold Tolerance

用含质粒pYF8631的根癌农杆菌EHA105菌株转化‘巴西’香蕉(Musa AAA Cavendish subgroup cv.‘Brazil’)的假茎横切薄片,在含有250 mg/L卡那霉素和500 mg/L羧苄青霉素的MS培养基上诱导不定芽,获得5株GUS阳性苗。经PCR、RT-PCR检测,发现其中2株可以合成ALAS mRNA,表明YHem1基因已经整合到基因组中并且能够正常表达。测定香蕉内源ALA含量、ALAS活性和叶绿素相对含量(SPAD)表明,转基因植株具有ALAS活性,其ALA含量和叶绿素含量均显著高于野生型对照。7℃低温处理后的叶绿素快速诱导荧光动力曲线测定表明,转基因香蕉叶片光合电子转换能力显著高于野生型,表明转化YHem1基因可以提高香蕉耐冷性。

The thin slices of pesudostems of banana （Musa AAA Cavendish subgroup cv.‘Brazil’） were used as the explants to transform YHem1 gene by Agrobacterium tumefaciens strain EHA105 harboring pYF8631 plasmids and 5 GUS-positive regenerated buds were obtained on MS culture media containing 250 mg/L kanamycin and 500 mg/L carbenicillin.PCR and RT-PCR detection showed that two of them were transgenic,because only they could synthesize mRNA.Furthermore,they could biosynthesize more endogenous ALA due to the additional ALAS activity,with higher SPAD than the wild type.The detection of the chlorophyll fast induction fluorescence of banana leaves treated by 7 ℃ chilling showed that over-production of ALA in YHem1 transgenic banana might improve cold tolerance of banana in photosynthetic electron conversion ability.Thus,YHem1 transformation can improve chilling tolerance for banana plants.