中文摘要：

以核盘菌菌株NGA4提取的总RNA为模版,利用RT-PCR技术扩增获得SsXYN基因的全长cDNA片段,将其克隆到pMD19-T载体上,菌落PCR、酶切鉴定和cDNA测序结果表明成功克隆了核盘菌SsXYN基因。从pMD19-T：SsXYN载体上,用BamH I和Sal I双酶切切下目的基因片段,将该基因片段连接到原核表达载体pET32a中。菌落PCR和酶切鉴定结果显示成功构建了表达载体pET32a：SsXYN。利用热击法将该重组表达载体导入大肠杆菌BL21,获得携带SsXYN基因的大肠杆菌菌株,为进一步研究激发子诱发植物抗病性机理奠定了基础。

英文摘要：

Total RNA was extracted from Sclerotinia sclerotiorum NGA4mycelia and used as the template to amplify the full length of cDNA of SsXYN gene by RT-PCR,and the gene fragment was subsequently cloned into pMD19-T vector.The results of bacterial colony PCR,enzyme analysis and sequencing analysis indicated that the S.sclerotiorum SsXYN gene was successfully cloned.SsXYN gene was digested completely from pMD19-T ： SsXYN by BamH I and Sal I,and then was cloned into expression vector pET32a.The results of bacterial colony PCR and enzyme analysis showed the expression vector pET32a ： SsXYN was successfully constructed.After that,the recombinant expression vector was carried into E.coli BL21 by heat-shock transformation,and the strain of E.coli BL21 carrying SsXYN gene was obtained.The study provides a basis for our understanding of the elicitor SsXYN downstream signaling pathway in plant immunity.