Differential activation of defense-related genes in susceptible and resistant pepper cultivars infected with Phytophthora capsici.
This study investigated the expression pattern of genes encoding for a basic PR-1 protein, a basic beta-1,3-glucanase, a peroxidase, and a sesquiterpene cyclase involved in defense responses in three pepper cultivars with different levels of resistance to Phytophthora capsici. All genes were up-regulated in infected stems of the pepper cultivars, with expression being detected 8h post-inoculation. mRNA levels of these genes increased markedly by 24h post-inoculation, and maximal induction levels were observed for the PR-1 and sesquiterpene cyclase genes. PR-1, peroxidase, and sesquiterpene genes were always expressed at higher levels in resistant cultivars than in the susceptible cultivar, although up-regulation was observed in both, suggesting that the differences between these pepper genotypes in susceptibility and resistance are a matter of the timing and magnitude of the defense response.
Silvar
Cristina
C
Departamento de Bioloxía Animal, Bioloxía Vexetal e Ecoloxía, Universidade da Coruña, Campus da Zapateira, Spain.
Merino
Fuencisla
F
Díaz
José
J
D002212:Capsicum / Q000378:metabolism* / Q000382:microbiology*; D018506:Gene Expression Regulation, Plant / Q000502:physiology*; D020022:Genetic Predisposition to Disease; D010838:Phytophthora / Q000502:physiology*; D010935:Plant Diseases / Q000235:genetics* / Q000382:microbiology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism
D010940:Plant Proteins