Ecology, infestation levels, and populations of Anthonomus weevils (Coleoptera : Curculionidae) on Malpighia glabra in Mexico

The ecology, infestation levels, and populations of Anthonomus weevils were documented in a diflubenzuron (Dimilin)-treated Malpighia glabra (L.) grov e in El Trapiche, Mexico, from January 1995 to March 1998 and in an untreat ed grove in El Petacal (approximate to 42 km away) from June 1997 to April 1998. Anthonomus caracasius (Faust) comprised 50-87% of the adult weevils f rom July 1997 through March 1998 in El Trapiche. A. sisyphus Clark comprise d 3-25% of the adult weevils during the same period and A. alboscutellatus Champion 0-22%. A. caracasius was not found in El Petacal, and A. sisyphus represented 38 - 100% of adults at this site from Tune 1997 to April 1998. A. alboscutellatus represented 0 - 50% of adults during this period in El P etacal. A. unipustulatus Champion was rare at both sites. A. sisyphus devel oped only in fruits. A. unipustulatus developed inside wild Malpighiaceae f ruit, A caracasius and A. alboscutellatus developed only in flower buds. Up to 30 and 15% of fruits from El Trapiche and El Petacal, respectively, wer e positive for weevil eggs in 1997. Eggs normally occurred singly on the lo wer half of fruits. Up to 74 and 97% of fruits from El Trapiche and El Peta cal, respectively, were infested with larvae, pupae, and adults in 1997. A. sisyphus, A. caracasius, and A. alboscutellatus were found throughout the year on M. glabra, but numbers were highest during the rainy season, from J une to November, in El Trapiche from 1995 to 1998. M. glabra fruit producti on was highest from April to lune, before the time when weevils were most a bundant. There were no correlations between adult weevil population densiti es and fruit yields 3 yr, probably because of unnatural flowering cycles ca used by year-round irrigation.