Secondary Metabolite Changes in Pecan (<i>Carya illinoensis</i>) Tissue Damaged by <i>Euplatypus segnis</i> Chapuis and Associated Fungi

Abstract

Problem statement:The borer insect Euplatypus segnis Chapuis is associated to Fusarium solani, Fusarium oxysporum, Alternariaalternata and Botryodiplodia theobromae fungi which produce regressive death in pecan (Carya illinoensis) trees. In the Mexico northern have been reported loses estimatesof more than 20% in production by the combination of insects and phytopathogen organisms. It also has been observed that some trees can survive with or without chemical treatment. Approach: The aim of present study was to determine the biochemical changes (contained of nitrogen, crude protein, terpen, condensed and hydrolyzable tannins, cellulose, lignin and silicium) in tissue of pecan trees cv. Western colonized by Ambrosia Borer (Euplatypus segnis Chapuis) and associated fungi complex. Three damaged trees and three healthy trees were sampled in three different plantations in each one of three Coahuila State localities. The responses variables were analyzed under a nested design, Tukey s test (p<0.05) was used to compare mean treatment differences. Results: Dataindicated that content of: terpenes, hydrolyzables tannins, cellulose, lignin and silicium increased significantly in the damaged trees in comparison to healthy trees. Conclusion: This results allowed inferring that these components increased as a chemical defense answer to insect invasion and to the enzymatic action of the associated phyto-pathogenic fungi.