Xanthomonas Fragariae Genetic Variability and Its Severity on Strawberry (Frigaria X Ananassa duch) Genotypes
Xanthomonas fragariae is the causative agent of the angular leaf spot of strawberries (FragariaXananassa Duch). This microorganism is subject to quarantine for the mobilization and transport of propagation plant material in several countries. There is no information about the pathogen’s genetic diversity and its severity on commercial varieties in Mexico. The objective of this study was to find out X. fragariae’s genetic variability and evaluate its severity on different strawberry genetic materials. To achieve this, a phylogenetic analysis was carried out with partial sequences of the hrp and gyrB genes from 14 X. fragariae isolates collected from production locations in the Mexicans states of Michoacán, Jalisco, and Puebla. The phylogenetic tree showed 99 % similarity among the isolates analyzed. In order to obtain X. fragariae-resistant strawberry genotypes, for commercial use and in genetic improvement programs, a X. fragariae suspension was inoculated, injected and sprayed, in two commercial varieties and five genotypes. The symptom severity was evaluated using a diagrammatic scale. FragLa and FragMa strawberry genotypes showed the lowest severity values. This is the first study in Mexico about the X. fragariae’s genetic variability and its severity on strawberry genotypes.