Microrganismos associados a frutos de diferentes cultivares de noz Pecan

Abstract

The knowledgement of the natural behavior of the main diseases of Pecan nut is of utmost importance for the stablishment of an implantation plan for that culture. The phytosanitary control and cultural treatments should be performed in order not to change the quality of the final product. Nuts harvest in 2005 from Uraí–PR of Burkett, Frotscher and Moneymaker cultivars, were evaluated in order to identify and quantify associated microorganisms in the nuts and fruit cover, as well to observe the differences among the microorganisms that colonize the different cultivars. The fruits were evaluated at post–harvest, thirty days kept in natural temperature, through filter paper method, being submitted or not to surface assepsy. The fungi Cladosporium caryigenum, rancification promoter to the almonds was observed on almonds and covers on the cultivars Burkett, Frotscher and Moneymaker; Fusarium sp., was observed in high concentration, on almonds as well as on the cover of all the studied cultivars; Cephalothecium roseum, responsible for the pink mildew, in almonds in the Frotscher cultivar. Aspergillus sp. and Penicillium sp., responsible for mold and aflatoxins formation, were observed in high amount on almonds of the Frotscher cultivar and in almonds and cover of Frotscher, Burkett and Moneymaker, respectively. The highest percentage of loss in yield was observed on the Burkett cultivar, cause of the incidence of Colletotrichum sp., agent responsible for antracnosis on the almonds which provokes causer darkness and deterioration of final product, leading it to discarding.