转HaNAC12基因棉花抗旱功能分析OA

[Objective]This study aims to analyze the effect of the Haloxylon ammodendron(C.A.Mey.)Bunge HaNAC12 gene on the fatty acid content and drought resistance of cotton,and to provide theoretical and technical guidance for cotton stress-resistant breeding.[Methods]The HaNAC12 gene was introduced into cotton through the cotton shoot apical meristem genetic transformation system.After molecular detection of T0 and T1 generation plants,the phenotypic and physiological indexes differences between transgenic and non-transgenic cotton were compared through drought stress experiments.[Results]After 30 days of natural drought stress(T30 treatment),the plant height of transgenic cotton was significantly increased by 11％compared with the non-transgenic control,and the degree of leaf wilting was less than that of the control.Physiological index analysis of cotton leaves under T30 treatment showed that the content of malondialdehyde in transgenic cotton was significantly 34％lower than that in the control,with less damage to the plasma membrane;the contents of soluble sugar,proline and chlorophyll were significantly 66％,89％and 50％higher than those in the control,respectively,with stronger osmotic adjustment ability;the activities of superoxide,peroxidase and catalase dismutase were significantly 94％,25％and 58％higher than those in the control,respectively,with stronger ability to scavenge reactive oxygen species.Under the T30 treatament,the expression levels of genes related to fatty acid metabolism,such as fatty acid synthase and desaturase,in transgenic cotton were significantly higher than those in the control after drought stress,and the content of free fatty acids in transgenic cotton was significantly 50％higher than that in non-transgenic cotton.There were no significant differences in leaf phenotypes and physiological and biochemical indexes between transgenic and non-transgenic cotton in the normal watering group.[Conclusion]The HaNAC12 may enhance the drought stress tolerance of cotton seedlings by promoting the synthesis and accumulation of fatty acids,providing new gene resources and material support for the genetic improvement of cotton drought resistance.