Transcriptomic analysis identifies candidate genes for Aphanomyces root rot disease resistance in pea

Area of Science:

• Plant pathology
• Plant genomics
• Molecular biology

Background:

• Aphanomyces euteiches causes root rot in peas, leading to yield loss.
• Pea resistance to Aphanomyces root rot (ARR) is complex, with individual gene roles unclear.
• Understanding pea immune responses is crucial for developing resistant cultivars.

Purpose of the Study:

• To investigate gene expression differences in pea genotypes with varying resistance to Aphanomyces euteiches.
• To identify candidate genes involved in the pea immune response to ARR.
• To elucidate the molecular mechanisms underlying resistance and susceptibility in peas.

Main Methods:

• Transcriptomic analysis of two pea genotypes ('Linnea' and 'PI180693') inoculated with A. euteiches.
• Differential gene expression analysis at 6, 20, and 48 hours post-inoculation.
• Cross-referencing gene expression data with known ARR resistance loci.

Main Results:

• Identified a time- and genotype-dependent immune response involving transcription factors and hormone signaling pathways (JA, ABA).
• Discovered 39 candidate disease resistance genes, particularly at later infection stages.
• Found a unique upregulated gene, Psat7g091800.1, in the resistant genotype, encoding a potential immune receptor.

Conclusions:

• Provided insights into gene expression dynamics during pea immune responses to A. euteiches.
• Identified 39 candidate ARR resistance genes in pea for further study.
• Highlighted Psat7g091800.1 as a potential key immune receptor for functional validation.