LABORATORY EVALUATION OF STEINERNEMATID A ND HETERORHABDITID NEMATODES FOR BIOLOGICAL-CONTROL OF THE COFFEE BERRY BORER, HYPOTHENEMUS-HAMPEI FERR

Eight nonselective insect-parasitic nematodes from two families, Stein ernematidae and Heterorhabditidae, were selected for trials under labo ratory conditions to determine pathogenicity against the coffee berry borer, Hypothenemus hampei Ferr. The experimental design was based upo n pergamine coffee set in sand. Included in the tests were a variety o f strains: one Costa Rican and three native strains of Steinernema spp . from Mexico; one commercial strain of Steinernema carpocapsae; and t hree Costa Rican strains of Heterorhabditis sp. Mortality between 10-9 0% was observed when the nematodes were applied to the sand at concent rations of 12.5-400 infective juveniles per insect. Four strains displ ayed relatively higher levels of pathogenicity, three of which were He terorhabditis sp., the other one was a commercial strain of Steinernem a carpocapsae. An LC50 of 60 infective juveniles per insect was observ ed for the most virulent strain LIM-1 Heterorhabditis sp.