Phytosanitary characterizaction of Quercus obtusata Bonpl., in a mountain cloud forest, Xicotepec, Puebla

Abstract

Cloud forests (CF) are part of the great diversity of plant communities in Mexico, covering around 10 % of the diversity that exists only in 5 % of the territory. Quercus is one of the most representative and abundant tree genera in montane cloud forests, and it is important because of the ecosystemic services that it provides. Despite its importance, few studies have focused on the phytosanitary status of this genus in CFs. The present study determines the types of pathogenic organisms affecting the phytosanitary status of Quercus obtusata, which is endemic to Mexico. In 2017, a quota sampling was carried out in three sites with different conservation degrees during the rainy and the dry seasons. The height and the diameter at breast height of each tree were measured; three branches were collected from each individual in order to analyze the organisms present on the leaves― and classified according to a scale of damage. The correspondence analysis evidenced a significant association (x² p<0.001) between the variables sites and scale of damage, i.e. between the disturbed and intermediate sites and the more severe degrees of infection. During the dry season, the three sites exhibited a larger number of infected leaves. Mainly two types of gallwasps belonging to the genera Andricus and Kinseyella of the Cynipidae family were obtained, as well as various types of arthropods and defoliators.