Henares Bernadette M, Blake Sara N, Farfan-Caceres Lina, Tahghighi Hediyeh, Debler Johannes W, Russ Michelle H, Farquharson Elizabeth A, Rose Jade A, Khani Mohsen, Davidson Jennifer A, Kamphuis Lars G, Lee Robert C
Centre for Crop and Disease Management, School of Molecular and Life Sciences, Curtin University, Bentley, WA 6102, Australia.
Pulse and Oilseed Pathology, Plant Health & Biosecurity, Crop Sciences, South Australian Research and Development Institute, Adelaide, SA 5064 Australia.
Phytopathology. 2023 Aug;113(8):1515-1524. doi: 10.1094/PHYTO-10-22-0397-R. Epub 2023 Oct 1.
, the causal organism of Ascochyta blight (AB) of lentil (), has been shown to produce an avirulence effector protein that mediates AB resistance in certain lentil cultivars. The two known forms of the effector protein were identified from a biparental mapping population between isolates that have reciprocal virulence on 'PBA Hurricane XT' and 'Nipper'. The effector AlAvr1-1 was described for the PBA Hurricane XT-avirulent isolate P94-24 and AlAvr1-2 characterized in the PBA Hurricane XT-virulent isolate Kewell. Here, we performed a genome-wide association study to identify other loci associated with AB for a differential set of lentil cultivars from a diverse panel of isolates collected in the Australian lentil-growing regions from 2013 to 2020. The chromosome 3 locus was strongly associated with the PBA Hurricane XT, 'Indianhead', and Nipper disease responses, but one other genomic region on chromosome 11 was also associated with the Nipper disease trait. Our results corroborate earlier work that identified the locus for field-collected isolates that span the period before release and after widespread adoption of PBA Hurricane XT. A multiplex PCR assay was developed to differentiate the genes and to predict PBA Hurricane XT avirulence and pathotype designation in the diversity panel. Increasing numbers of the PBA Hurricane XT-virulent pathotype 2 isolates across that time indicate strong selection for isolates with the allele. Furthermore, one other region of the genome may contribute to the pathogen-host interaction for lentil AB.
扁豆褐斑病（AB）的病原菌Ascochyta lentis已被证明能产生一种无毒效应蛋白，该蛋白在某些扁豆品种中介导对AB的抗性。从对“PBA Hurricane XT”和“Nipper”具有相互毒力的分离株之间的双亲作图群体中鉴定出效应蛋白的两种已知形式。效应蛋白AlAvr1 - 1是针对PBA Hurricane XT无毒分离株P94 - 24描述的，而AlAvr1 - 2是在PBA Hurricane XT有毒分离株Kewell中鉴定的。在这里，我们进行了全基因组关联研究，以确定与AB相关的其他基因座，这些基因座来自于2013年至2020年在澳大利亚扁豆种植区收集的不同分离株组成的差异扁豆品种集。3号染色体位点与PBA Hurricane XT、“Indianhead”和Nipper的病害反应密切相关，但11号染色体上的另一个基因组区域也与Nipper的病害性状相关。我们的结果证实了早期的研究工作，该研究确定了在PBA Hurricane XT发布之前和广泛采用之后这段时间内田间收集的分离株的该位点。开发了一种多重PCR检测方法来区分这些基因，并预测多样性面板中PBA Hurricane XT的无毒和致病型指定。在那段时间里，PBA Hurricane XT致病型2分离株的数量不断增加，这表明对具有该等位基因的分离株有强烈的选择。此外，Ascochyta lentis基因组的另一个区域可能有助于扁豆褐斑病的病原菌 - 宿主相互作用。
