Identification of Novel Sources of Resistance to Ascochyta Blight in a Collection of Wild Cicer Accessions

Phytopathology. 2021 Feb;111(2):369-379. doi: 10.1094/PHYTO-04-20-0137-R. Epub 2021 Jan 16.

Abstract

Chickpea production is constrained worldwide by the necrotrophic fungal pathogen Ascochyta rabiei, the causal agent of Ascochyta blight (AB). To reduce the impact of this disease, novel sources of resistance are required in chickpea cultivars. Here, we screened a new collection of wild Cicer accessions for AB resistance and identified accessions resistant to multiple, highly pathogenic isolates. In addition to this, analyses demonstrated that some collection sites of C. echinospermum harbor predominantly resistant accessions, knowledge that can inform future collection missions. Furthermore, a genome-wide association study identified regions of the C. reticulatum genome associated with AB resistance and investigation of these regions identified candidate resistance genes. Taken together, these results can be utilized to enhance the resistance of chickpea cultivars to this globally yield-limiting disease.

Keywords: Ascochyta blight; Ascochyta rabiei; Cicer echinospermum; Cicer reticulatum; Didymella rabiei; Phoma rabiei; crop wild relatives; disease resistance; genetics; germplasm collection; resistance; wild chickpea.

MeSH terms

  • Ascomycota
  • Cicer* / genetics
  • Genome-Wide Association Study
  • Plant Diseases
  • Quantitative Trait Loci

Supplementary concepts

  • Ascochyta rabiei