StBAG3基因介导的马铃薯对晚疫病抗性研究

Study on StBAG3 Gene Mediated Potato Resistance to Late Blight

为了探究来源于马铃薯中的StBAG3基因在马铃薯抗性建立过程中可能具有的功能,以夏坡蒂马铃薯的离体叶片为试验材料,利用马铃薯的瞬时表达体系对StBAG3基因的功能进行了初步的研究。结果表明,在瞬时表达StBAG3基因的马铃薯离体叶片上人工接种马铃薯晚疫病菌,24,48,72,96 h后接种位置病斑的相对面积较对照病斑显著减少了1.92~39.15百分点,说明瞬时表达StBAG3基因后显著提高了马铃薯对晚疫病菌的抗性水平。这一结果也从对接种部位坏死细胞的染色中得到了证实。H2O2定性和定量测定的结果表明,瞬时表达StBAG3基因后接种部位H202积累量在接种后0~48 h差异不显著,接种后72,96 h与对照差异显著,二者均在72 h达到最大值,分别为0.146,0.086μmol/g。ROS清除酶活性测定的结果表明,接种后瞬时表达StBAG3基因部位SOD和CAT的活性随着接种时间推移,变化的模式有所差异,但二者在0~96 h均高于对照叶片,而POD的活性在接种后0~72 h与对照叶片没有显著差异,仅在接种后96 h显著高于对照叶片,间接证明了H2O2参与了StBAG3基因介导的正向调控马铃薯对晚疫病的抗性建立过程。由此可见,StBAG3基因能够提高马铃薯对晚疫病的抗性水平。

In order to explore the possible functions of StBAG3 gene derived from potato in the process of potato resistance establishment,this study used the in vitro leaves of Shepody as experimental material,and used the transient expression system of potato to explore the preliminary function of StBAG3 gene.The results showed that Phytophthora infestans was inoculated on the leaves of potato expressing StBAG3 gene transiently,after 24,48,72,96 h,the relative lesions area was significantly reduced by 1.92-39.15 percentage points compared with the control,indicating transient expression of the StBAG3 gene significantly increased potato resistance to Phytophthora infestans.This result was also confirmed by the staining of necrotic cells at the inoculation site.The results of qualitative and quantitative determination of H 2O 2 showed that the accumulation of H 2O 2 at the inoculation site after transient expression of StBAG3 gene was not significantly different from 0 to 48 h after inoculation,they significantly different from control at 72,96 h after inoculation,both reached the maximum at 72 h,0.146,0.086μmol/g,respectively.The results of ROS scavenging enzymes activity assay showed that the activity of SOD and CAT enzymes were varied with the inoculation time after transient expression of StBAG3 gene,but both were higher than the control leaves at 0-96 h.POD activity was not significantly different from the control leaves at 0-72 h after inoculation,only significantly higher than control leaves at 96 h after inoculation.It was indirectly proved that H 2O 2 was involved in StBAG3 gene mediated positive regulation establishment process of potato resistance to late blight.The results showed that StBAG3 gene can increase potato resistance to late blight.