Haplotype analysis and genetic variability of Togninia minima from different geographic sources

Abstract

Togninia minima (anamorph Phaeoacremonium aleophilum) is one of the main fungi responsible for trunk diseases of grapevines and other woody hosts worldwide. Sequences of protein-coding genes of isolates from countries in different continents have been published, presenting a useful resource for examination of the diversity and spatial distribution of T. minima genotypes. Single nucleotide polymorphisms (SNPs) detected in public sequences of the actin and partial β-tubulin genes were used to assess the genetic variability and to determine haplotypes of isolates of this species from different sources. The Italian sample showed the greatest allele number and the largest number of haplotypes. Most haplotypes were present in more than one country, except for haplotype 11010 which was found only in Italy and 10111 found only in Canada. Haplotype 11111 was the most conspicuous and cosmopolitan, being present in six countries and on three host plant species. One observed polymorphism in the non-coding region of the β-tubulin gene could be targeted with allele-specific primers to detect this particular haplotype.