应用竞争力指数分析III型效应子SKWP对青枯菌在寄主植物体内增殖能力的影响

Analysis of the SKWP effectors to bacterial fitness in host plant by a novel competition assay

摘要:

[目的]研究Ⅲ型效应子SKWP对青枯菌OE1-1在寄主植物体内增殖能力的影响。[方法]构建青枯菌RK7197（野生型突变体，带Gm抗性）和SKWP单基因缺失突变体（带PB抗性），通过竞争力指数分析SKWP各效应子对青枯菌OE1-1在叶片组织内增殖能力的影响。[结果]竞争力指数适合在寄主植物茄子上分析各效应子功能，6个SKWP效应子对OE1-1细菌增殖能力影响不同，SKWP4影响最明显。[结论]竞争力指数可提供一个新视野来分析SKWP各效应子对青枯菌OE1-1在寄主茄子上增殖能力的影响。

关键词:青枯菌OE1-1;SKWP;竞争力指数分析;细菌增殖

Abstract:

[Objective] By testing the internal bacterial growth of SKWP mutants generated in Ralstonia solanacearum strain OE1-1, we evaluated the contribution of these SKWP effectors to bacterial fitness towards host plants. [Methods] The deletion mutant and complementation mutant of R. solanacearum OE1-1 were constructed. A competition assay in mixed infection was adopted to evaluate the contribution of the SKWP to bacterial fitness in tobacco (Nicotiana tabacum cv. Bright Yellow) and eggplant (Solanum melongena cv. Senryo-nigou). [Results] Eggplant was the appropriate host for competitive index (CI) assay of R. solanacearum strain OE1-1. All 6 SKWP mutants affected bacterial fitness in eggplant to some extent while SKWP4 appeared to be most important.[Conclusion] The SKWP effectors were important for bacterial proliferation in eggplant tissues according to the CI analysis, which paving a new way for further identification of the function on whole SKWP family.

Key words:Ralstonia solanacearum OE1-1;SKWP;CI assay;bacterial proliferation