Studies were conducted in South Carolina in 1981 and 1982 to determine the effect of mean levels of damage by a pest complex during early season and mid-season on first harvest and total yield of cotton. In 1981, the pest complex consisted of the bolf weevil, Anthonomus grandis Boheman, and Heliothis spp. (bollworm, H. zea [Boddie], and tobacco budworm, H. virescens [F.]). In 1982, the same pest complex was involved; additional damage during mid-season was caused by fall armyworm larvae, Spodoptera frugiperda (J. E. Smith). Different mean levels of damage resulted from spraying with recommended insecticides beginning early in the season compared to the middle of the season. All multiple regressions of yield on the insect complex indicated significant reduction in yield based on damage to squares, especially during mid-season when many irreplaceable losses occur. The slopes of the multiple regressions of total yield on the two mid-season damaged-square variables were similar. For 1981, the slope values of b1, and b2 indicated a loss of 57 and 168 kg/ha of seed cotton per 1% of damage, respectively. For 1982, the b1, and b2 values indicated a loss of 45 and 182 kg/ha of seed cotton per 1% of damage, respectively.
Document Type: Research Article
Publication date: February 1, 1985
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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.