Sclerotia morphology traits and mycelial growth rate are not informative variables for population studies of Sclerotinia sclerotiorum
2014
Lehner, Miller S.(Universidade Federal de Viçosa Programa de Pós-graduação em Genética e Melhoramento) | Paula Júnior, Trazilbo J.(EPAMIG) | Silva, Rhaphael A.(Universidade Federal de Viçosa) | Vieira, Rogério F.(EPAMIG) | Carneiro, José Eustáquio S.(Universidade Federal de Viçosa Departamento de Fitotecnia) | Mizubuti, Eduardo S. G.(Universidade Federal de Viçosa Departamento de Fitopatologia)
The usefulness of sclerotia morphology traits and mycelial growth rate to infer phenotypic variability in populations of Sclerotinia sclerotiorum associated with common beans in Minas Gerais State (MG) was assessed in two experiments. Isolates (131) were collected in the Northwestern, Alto Paranaíba, Zona da Mata and Southern regions of MG and the mycelial growth rate, the number, weight and dimensions (length, width and thickness) of sclerotia and mycelial pigmentation were assessed. There was a high variability among isolates, even among colonies of the same isolate. The variance of the first experiment for the mycelial growth rate, number, weight, length, width and thickness of sclerotia, were 0.01, 190.15, 0.01, 0.62, 0.12 and 0.05, whereas in the second, the variances were 0.01, 28.48, 0.002, 0.18, 0.06 and 0.03, respectively. Most correlations between traits were of low magnitude except that between length and width (r = 0.84, 'P < 0.001). Regarding colony pigmentation, non-pigmented, pigmented and highly pigmented isolates were identified, but for most isolates this characteristic varied between experiments. No groups based on phenotypic traits were detected. The morphological traits evaluated in the present study are not suitable for characterization of populations of S. sclerotiorum.
显示更多 [+] 显示较少 [-]