Genetic diversity of Venturia inaequalis isolates (Apple scab) in China and U.K. determined by SSR markers

Abstract

Apple scab caused by Venturia inaequalis is a serious disease of cultivated apple worldwide. In this study, we collected 132 V. inaequalis isolates from Shaanxi, Gansu, Xinjiang, and the U.K. and analyzed their genetic diversity by using 13 microsatellite markers. Cluster analysis based on population structure and genetic distances suggested high similarity among the four regions. Population differentiation values ranged from 0.044 to 0.155, indicating there is a high level of kinship among the four regions. All isolates could be divided into 5 lineages with a 0.76 similarity coefficient. Among the four regions, Shaanxi had only one lineage, Group II; Gansu had four lineages, Group I, Group II, Group IV, and Group V; Xinjiang had all five lineages, Group I, Group II, Group III, Group IV, and Group V; and the U.K. had three lineages, Group I, Group II and Group IV. High molecular variance was detected for populations in the four regions, with 91% of the variance occurring within the populations and 9% among the populations. Structure analysis there are three common ancestors of these four regions. The results of the present study shed light on the genetic diversity of V. inaequalis in Shaanxi, Gansu and Xinjiang, which will lead to the development of more effective management strategies and new resistant apple cultivars through molecular marker-assisted selection.

Genetic diversity of Venturia inaequalis isolates from the scabs in apple trees in Gansu Province, China, using AFLP markers

“…In this study, the AFLP molecular marker technique was used to analyze the genetic diversity of V. inaequalis from six different geographical regions of Gansu Province. The results showed that the populations of Jingning, Jingchuan, Lingtai, Maiji, Xifeng and Ning isolates were genetically similar and were consistent with the results of previous studies in China ( Hu et al, 2008 ; Fu et al, 2010a ; Li et al, 2021 ). The main environmental factors affecting the genetic variation of apples are the apple planting area and the pathogen hosts.…”

“…At the same time, by utilizing SSR to analyze the genetic diversity of V. inaequalis populaces within the UK and China, the results showed that the genetic relationship between both regions was relatively close. This was because most of the apple dwarf seedlings planted in Northwest China were from the EM system in the UK ( Li et al., 2021 ).…”

Genetic Diversity of Venturia inaequalis in Latvia Revealed by Microsatellite Markers

“…The diversity and population structure of V. inaequalis has caught the attention of research groups in Europe and other regions for decades [ 10 , 13 , 15 , 31 ]. In contrast, in some regions only recently studies on the genetic diversity of this economically important pathogen have been carried out [ 9 , 18 , 42 ]. This study is the first report about V. inaequalis population diversity in Latvia based on the genotyping within twelve microsatellite loci.…”

“…The favourable weather conditions during the winter and spring in Latvia may positively affect annual sexual reproduction, thus resulting in higher genetic diversity within populations. In addition, the high diversity of cultivars may also have a significant differential selection pressure on V. inaequalis in orchards [ 14 , 42 ]. Our results were consistent with previous works [ 9 , 18 , 19 , 42 ].…”

“…In addition, the high diversity of cultivars may also have a significant differential selection pressure on V. inaequalis in orchards [ 14 , 42 ]. Our results were consistent with previous works [ 9 , 18 , 19 , 42 ].…”