ARS | Publication request: Susceptibility of the parasitoid Phymastichus coffea LaSalle (Hymenoptera: Eulophidae) to Beauveria bassiana (Bals.) Vuill. under laboratory conditions

Submitted to: Neotropical Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: July 14, 2009
Publication Date: October 1, 2009
Citation: Castillo, A., Gomez, J., Infante, F., Vega, F.E. 2009. Susceptibility of the parasitoid Phymastichus coffea LaSalle (Hymenoptera: Eulophidae) to Beauveria bassiana (Bals.) Vuill. under laboratory conditions. Neotropical Entomology. 38:665-670.

Interpretive Summary: The coffee berry borer is the most devastating pest of coffee throughout the world. Eggs are deposited inside coffee berries and insects feed on the coffee seed, severely reducing yields. One mechanism to manage this insect involves the use of other insects, such as Phymastichus coffea, that lay their eggs inside the coffee berry borer, eventually killing it. We have conducted studies aimed at understanding the effects of the fungal insect pathogen Beauveria bassiana on P. coffeae. B. bassiana infection causes 100% larval mortality on P. coffea, and reduces adult longevity.These results could be valuable when considering the use of both organisms in the field, especially in an integrated pest management program. Our findings will be of use to coffee scientists, entomologists, and the coffee industry.

Technical Abstract: The coffee berry borer, Hypothenemus hampei, is the most important pest of coffee worldwide. Beauveria bassiana is a generalist entomopathogenic fungus widely used by coffee farmers to control this pest. Phymastichus coffea is an African endoparasitoid of H. hampei adults recently imported to several Latin American and Caribbean countries to control this pest. The objective of this study was to determine if B. bassiana is detrimental to P. coffea. The susceptibility of the parasitoid was evaluated in terms of adult survivorship, mean lethal concentration (LC50), reproduction and immature stages mortality. The results show that the LC50 for adults was 0.11% equivalent to 9.53 x 107 conidia/ml of B. bassiana. The main effect of the fungus on P. coffea adults was a reduction of 22% of its longevity and a mortality of 100% for immature stages. It was determined that P. coffea was capable of disseminating spores of B. bassiana to non-infected H. hampei adults, which could indirectly cause the death of its own progeny. These results could be valuable when considering the use of both organisms in the field, especially in an integrated pest management program.