Abstract: The halophyte Paspalum vaginatum is a perennial herb with extremely salt tolerance. In this study,PvCIPK9 gene responsive to salt stress was screened from the transcriptome of Paspalum vaginatum,the full length of CDS sequence of PvCIPK9 gene was cloned,and its expression pattern and promoter elements were analyzed. In order to further study the salt stress resistance of PvCIPK9 gene,the overexpression vector of PvCIPK9 was constructed and transgenic Arabidopsis was obtained by agrobacterium-mediated inflorescence infection. Subsequently,salt tolerance of transgenic Arabidopsis was analyzed. The results showed that the growth phenotype of transgenic Arabidopsis was significantly better under salt stress compared to wild type,and the seed germination rate and relative growth yield of transgenic Arabidopsis were significantly higher under salt stress than that of wild type. In addition,the antioxidant enzyme activity of transgenic Arabidopsis was also significantly higher after salt treatment. The above results showed that overexpression of PvCIPK9 gene enhanced the resistance to salt stress in Arabidopsis. This study is helpful to further understanding the molecular function of PvCIPK9 in response to salt stress,and provides a theoretical basis for genetic improvement of crop salt tolerance.

Key words: Salt tolerance, Paspalum vaginatum, Arabidopsis thaliana, PvCIPK9

摘要： 盐生植物海雀稗（Paspalums vaginatium）是一种极其耐盐的多年生草本植物。本研究从海雀稗转录组数据中筛选对盐胁迫响应的PvCIPK9基因，克隆了PvCIPK9基因CDS序列全长，并对其表达模式、启动子元件等进行分析。为研究PvCIPK9基因的耐盐功能，构建了PvCIPK9过表达载体，采用农杆菌介导的花序侵染法转化拟南芥（Arabidopsis thaliana），获得过表达PvCIPK9的转基因拟南芥（Arabidopsis thaliana），对转基因拟南芥的耐盐性进行鉴定。结果表明，盐胁迫条件下，转基因拟南芥的生长表型显著优于野生型，转基因拟南芥在盐胁迫下的种子萌发率及相对生长量均显著高于野生型；此外，盐处理后转基因拟南芥的抗氧化酶活性也显著高于野生型，以上结果初步说明过表达PvCIPK9基因增强了拟南芥对盐胁迫的抵抗能力。本研究为深入解析海雀稗PvCIPK9在植物耐盐性中的作用奠定了基础。

关键词: 耐盐性, 海雀稗, 拟南芥, PvCIPK9