A theoretical economic Injury level (EIL) was devised for Contarinia texana (Felt) infesting buds of guar, Cyamopsis tetragonoloba (L.) Taub. Since the presence of only 1 midge larva results in the abortion of a bud, the EIL is based on number of infested buds per sampling unit rather than on the larval population. Factors affecting the EIL include projected yield, management costs, market value of seed, plant diseases, date of planting, timing and amount of precipitation, and budding phenology. Since a strong correlation between the destruction of buds and yield loss in guar was found only for 45 through 90 days post emergence of the plants, control of the midge should be restricted to that period of buckling phenology. The theoretical EILs for C. texana in guar at the peak-budding period are 52, 38, 28, and 12 infested buds/row ft for guar having projected yields of 500, 750, 1000, 1500 lb of seed/acre, respectively.
Document Type: Research Article
Publication date: October 1, 1976
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Journal of Economic Entomology is published bimonthly in February, April, June, August, October, and December. The journal publishes articles on the economic significance of insects and is divided into the following sections: apiculture & social insects; arthropods in relation to plant disease; forum; insecticide resistance and resistance management; ecotoxicology; biological and microbial control; ecology and behavior; sampling and biostatistics; household and structural insects; medical entomology; molecular entomology; veterinary entomology; forest entomology; horticultural entomology; field and forage crops, and small grains; stored-product; commodity treatment and quarantine entomology; and plant resistance. In addition to research papers, Journal of Economic Entomology publishes Letters to the Editor, interpretive articles in a Forum section, Short Communications, Rapid Communications, and Book Reviews.