Identification of a Gene Conferring High Levels of Resistance to Verticillium Wilt in Solanum chacoense

Abstract

Verticillium wilt (Verticillium albo-atrum) is an important disease affecting potato tuber yield and quality. In North America the major commercial cultivars are susceptible and management strategies for control of the pathogen rely mainly on soil fumigation and crop rotation. In this study 398 genotypes from accessions of Solanum berthaultii, S. chacoense, and S. tarijense were screened for resistance to Verticillium albo-atrum. Resistant genotypes were identified in all but two accessions; however, results indicate that tolerance is more common than resistance. We identified two genotypes in S. chacoense (PI 472819) that had low stem-colonization levels and also did not develop wilt symptoms when inoculated with V. albo-atrum. These genotypes and a susceptible genotype from PI 472810 (S. chacoense) were studied to determine genetic inheritance. Segregation ratios in F1, F2, and backcross populations indicated that resistance in one of the resistant genotypes (18-21R) was controlled by a single dominant gene. Transfer of the Vc gene to tetraploid germ plasm could provide effective and economical control of Verticillium wilt.

Diversity, Pathogenicity, and Management of Verticillium Species

“…Adding an additional layer of complexity, it is possible that different types of Verticillium wilt resistance are controlled by different genetic systems. For example, tolerance is a polygenic trait in diploid S. chacoense, whereas resistance to infection and colonization is apparently due to a major gene (95). Resistance in at least some cotton cultivars is quantitative and was associated with three loci on chromosome 11 (19).…”

Tomato Ve disease resistance genes encode cell surface-like receptors

“…Several species of Verticillium have been reported to cause wilt and control often has relied on the use of expensive chemical fumigants that may impact health and environment adversely. In a few cases, effective control of verticillium wilt has been reported in specific crops that exhibit race-specific resistance (2,3).…”

Genetic Dissection ofVerticilliumWilt Resistance Mediated by Tomato Ve1

“…In several plant species, including alfalfa (Medicago sativa), cotton (Gossypium hirsutum), potato (Solanum tuberosum), strawberry (Fragaria vesca), sunflower (Helianthus annuus), and tomato (Solanum lycopersicum), sources of genetic resistance to Verticillium have been described (Schaible et al, 1951;Lynch et al, 1997, Bae et al, 2008. However, a locus responsible for resistance against Verticillium has been cloned only from tomato (Kawchuk et al, 2001).…”