Mitochondrial characteristics of the powdery mildew genus Erysiphe revealed an extraordinary evolution in...

Area of Science:

• Mycology
• Plant Pathology
• Genomics

Background:

• The genus Erysiphe comprises obligate parasites responsible for powdery mildew diseases in numerous plant species.
• Limited knowledge exists regarding the mitogenome architecture of Erysiphe and its role in lifestyle adaptability.

Purpose of the Study:

• To assemble and analyze the first complete mitochondrial genome (mitogenome) of the rubber tree powdery mildew pathogen, Erysiphe quercicola.
• To investigate the evolutionary patterns and genomic plasticity of Erysiphe mitogenomes in relation to their obligate biotrophic lifestyle.

Main Methods:

• Whole-genome sequencing and assembly of the Erysiphe quercicola mitogenome.
• Comparative analysis of mitogenome architecture, gene content, and codon usage bias across Erysiphe species.
• Phylogenetic analysis of Ascomycota species to understand genetic divergence.
• Analysis of evolutionary pressures on fungal protein-coding genes (PCGs).

Main Results:

• The complete mitogenome of Erysiphe quercicola was assembled (190,559 bp).
• Comparative analysis revealed conserved gene content and genome organization but extensive dynamic intron gain/loss events among Erysiphe species.
• Erysiphe species exhibited a flat distribution of evolutionary pressures on PCGs, with particularly high selection pressures on cox1, nad1, cob, and rps3 genes.

Conclusions:

• The findings provide novel insights into the evolutionary patterns enabling the obligate biotrophic lifestyle of the Erysiphe genus.
• The study highlights the high plasticity and population evolution of fungal mitogenomes, particularly in Erysiphe.