Effectors encoded by avirulence genes (Avr) interact with the Phytophthora sojae resistance gene (Rps) products to generate incompatible interactions. The virulence profile of P. sojae is rapidly evolving as a result of the large-scale deployment of Rps genes in soybean. For a successful exploitation of Rps genes, it is recommended that soybean growers use cultivars containing the Rps genes corresponding to Avr genes present in P. sojae populations present in their fields. Determination of the virulence profile of P. sojae isolates is critical for the selection of soybean cultivars. High-resolution melting curve (HRM) analysis is a powerful tool, first applied in medicine, for detecting mutations with potential applications in different biological fields. Here, we report the development of an HRM protocol, as an original approach to discriminate effectors, to differentiate P. sojae haplotypes for six Avr genes. An HRM assay was performed on 24 P. sojae isolates with different haplotypes collected from soybean fields across Canada. The results clearly confirmed that the HRM assay discriminated different virulence genotypes. Moreover, the HRM assay was able to differentiate multiple haplotypes representing small allelic variations. HRM-based prediction was validated by phenotyping assays. This HRM assay provides a unique, cost-effective and efficient tool to predict virulence pathotypes associated with six different Avr (1b, 1c, 1d, 1k, 3a and 6) genes from P. sojae, which can be applied in the deployment of appropriate Rps genes in soybean fields.

中文翻译：

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使用高分辨率熔解分析区分大豆疫霉无毒基因等位基因和单倍型的快速分子诊断工具

由无毒基因 ( Avr ) 编码的效应子与大豆疫霉抗性基因 ( Rps ) 产物相互作用，产生不相容的相互作用。由于Rps基因在大豆中的大规模部署，酱油疫霉的毒力谱正在迅速演变。为了成功利用Rps基因，建议大豆种植者使用含有 Rps 基因的品种，这些Rps基因与田间大豆 P. sojae群体中存在的Avr基因相对应。大豆疫霉分离株毒力特征的测定对于大豆品种的选择至关重要。高分辨率熔解曲线 (HRM) 分析是一种强大的工具，首先应用于医学，用于检测突变，在不同的生物领域具有潜在的应用。在这里，我们报告了 HRM 协议的开发，作为区分效应子的原始方法，以区分6 个Avr基因的P. sojae单倍型。对从加拿大各地大豆田收集的 24 株具有不同单倍型的大豆 P. sojae分离株进行了 HRM 测定。结果清楚地证实了 HRM 检测可以区分不同的毒力基因型。此外，HRM 测定能够区分代表小的等位基因变异的多个单倍型。基于 HRM 的预测通过表型分析进行了验证。这种 HRM 检测提供了一种独特的、经济高效的工具来预测与来自P. sojae的六种不同Avr ( 1b , 1c , 1d , 1k , 3a和6 ) 基因相关的毒力致病型，可应用于适当的部署大豆田中的Rps基因。