| Abstract: | In the Philippines, three bruchid species are considered major pests of
legumes: Callosobruchus chinensis (Linn); C. maculatus (F.) and
Acanthoscelides obtectus Say. They attack the following legume seeds:
pigeon pea (Cajanus cajan (L.) Millsp.), mungbean (Vigna radiata (L)
Wilczek), garden pea (Pisum sativum L.), string bean (Vigna
sesquipedalis Fruw.), cowpea (V. sinensis (L.) Savi), bush sitao (V.
sinensis (L.) x V. sesquipedalis Fruw.), soybean (Glycine max (L.)
Merr.), peanut (Arachis hypogaea L.), "balatong-aso" (Cassia tora L.),
hyacinth bean (Dolichos lablab L.), lima bean (Phaseolus lunatus L.),
common bean (P. vulgaris L.) and winged bean (Psophocarpus
tetragonolobus (L.) DC). Among these species, C. chinensis is the most
predominant and very serious in mungbean. The initial infestation of C.
chinensis commence in the field when the female weevils start laying
their eggs on fully developed pods of mungbean. Infestation at harvest
ranged from 7.8 to 9.88%. Losses can be as high as 80% to 100% within
three months when no proper control measure is applied. Weevil
infestation is prevented and/or controlled by: planting resistant
varieties, fumigation and thermal disinfestation, mechanical exclusion
and botanical and conventional insecticides. The potential of botanical
insecticides are being pursued.
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