Abstract
Characterization of Cryphonectria parasitica from Native Chestnut Trees in Mount Ida
Cryphonectria parasitica is a casual agent of chestnut blight worldwide and it has dramatically affect natural chestnut trees in Mountain Ida. Different biological control approaches have been proposed to constrain the disease. The pathogen has mating system with two alternate idiomorphies which may increase pathogen genetic variability due the recombination events. In this study, C. parasitica isolates were diagnosed with sequencing of the Translation Elongation Factor 1-? (Ef-1?) gene, and tested for their pathogenicity, determined the mating type, and investigated for if the isolates could be controlled by Trichoderma sp. which is isolated from the same lesion where some of the C. parasitica isolates were obtained. It was not detected any mutation in sequenced part of Ef-1 ? gene. All of the isolates were confirmed as pathogen in vitro assays by inoculation to apple fruit. Only one mating type (Mat1_1) was detected for some of the isolates. Trichoderma sp. isolates were suppressed in vitro growth rate of C. parasitica. Once they were inoculated on apple, both C. parasitica and Trichoderma sp. caused necrotic symptoms on the fruits and Trichoderma sp. did not affect lesion development by C. parasitica. Overall results present that wild chestnut trees in Mount Ida are under threat of chestnut blight pathogens which having similar aggressiveness and genetic identity and Trichoderma sp. may not be a powerful biocontrol agent to control C. parasitica in the ecosystem.
Keywords
Chestnut blight, Ef-1 ? gene, pathogenicity, mating type