Artículos de revistas
Evidência de que o fungo Rhizoctonia solani AG-1 IA adaptado à Urochloa na Colômbia mantém ampla gama de hospedeiros incluindo o milho
Fecha
2016-07-01Registro en:
Summa Phytopathologica, v. 42, n. 3, p. 228-232, 2016.
0100-5405
10.1590/0100-5405/2176
S0100-54052016000300228
2-s2.0-84987781490
S0100-54052016000300228.pdf
2635092058300854
0000-0003-2381-2792
Autor
Universidade Estadual Paulista (Unesp)
UNINCCA (Universidad INCA de Colombia)
Institución
Resumen
The fungus Rhizoctonia solani anastomosis group AG-1 IA has emerged as an important pathogen associated with foliar blight, collar rot and death of Urochloa (Brachiaria) forage pastures in South America. This study aimed to determine whether the adaptation of R. solani AG-1 IA to Urochloa spp. in Colombia promoted phenotypic differences in aggressiveness to distinct hosts. Our hypothesis was that the pathogen populations adapted to Urochloa spp. are not host-specialized and hence are not genetically isolated, thereby maintaining a broad host range, including the fabaceous plants cowpea and soybeans. We also determined whether two groups of isolates from populations of R. solani AG-1 IA sampled from Urochloa in Colombia have adaptive potential to emerge as maize pathogens. Besides the levels of disease severity in different hosts, we also determined the components of evolvability, such as the coefficient of genotypic variance (IG), the environmental variance (IE) and the heritability (h2). We concluded that: i) The adaptation of R. solani AG-1 IA to Urochloa spp. did not cause any phenotypic differences in aggressiveness to distinct hosts and therefore the pathogen maintains a broad host range. ii) The population of R. solani AG-1 IA from Urochloa hybrid Mulato in Colombia has adaptive potential to emerge as a maize pathogen.