Genetic Diversity of Venturia inaequalis in Latvia Revealed by Microsatellite Markers

Abstract

Apple scab caused by the ascomycete Venturia inaequalis is an economically significant disease worldwide. The annual sexual reproduction of V. inaequalis leads to high variation, changes in the population’s genetic structure and adaptations to the changing environment, including overcoming the host’s resistance. The objective of this study is to characterise and assess the genetic diversity of V. inaequalis populations in two main apple-growing regions in Latvia. In total, 143 V. inaequalis isolates were collected from Latvia, six reference strains with known virulence were obtained from other countries, and all strains were genotyped by 12 SSR markers. The SSR markers were highly variable and informative, identifying 158 alleles that ranged from two to 29 per locus. The Bayesian clustering identified three genetic lineages among the Latvian isolates that did not correlate to the geographic origin, host genotype, organ (leaves or fruits) from which the pathogen was isolated, time of collection, and type of isolation (single conidium or ascospore). The possible relatedness to virulence was detected when reference strains with known virulence were included in the analysis. Our findings correspond with previous studies demonstrating that V. inaequalis in Europe has a high genetic diversity within populations, but low diversity among the populations.

Strong Genetic Differentiation between Generalist Populations of Venturia inaequalis and Populations from Partially Resistant Apple Cultivars Carrying Rvi3 or Rvi5

“…Most studies suggested weak differentiation between V. inaequalis populations despite being separated by large geographic distances [44][45][46][47][48][49][50], with a few exceptions where mountainous or coastal regions with vastly differing climate conditions were also included in the study [51,52]. Besides environmental factors, host-specialization is among the major evolutionary forces guiding population differentiation.…”

Analysis of the Relationship between Short Tandem Repeats and Lactation Performance of Xinjiang Holstein Cows

“…In 2018, Polish scientist Dux discovered a microsatellite locus in the intron 23 region of insulin-like growth factor receptor 2 and signi cantly associated different genotypes of this locus with high milk yield, high milk fat percentage, and high milk protein level (Dux M et al 2018). Recently, many studies have analyzed STRs and SSRs in plants and microorganisms, for example, genetic diversity of Venturia inaequalis in Latvia (Sokolova et al 2022), STR locus comparison of cherry germplasm in Europe (Ordidge et al 2021), microsatellite loci related to drought tolerance traits in potato (Schumacher et (Hameed et al 2022), relationship between genetic diversity and phylogeny of cattle in Senegal (Sambe et al 2022), relationship between genetic diversity and phylogeny of Siberian black-skinned cattle (Aitnazarov et al 2021), genetic diversity of cattle in Kerala, India, and relationship between STR genetic diversity and quantitative trait variations of bull semen (Gororo et al 2021). There has been limited research on the correlation between microsatellite loci and milk production traits of Holstein cows, and there are no reports on microsatellite locus analysis of Holstein cows in Xinjiang.…”