|Chu, Chang Chi
|NATWICK, ERIC - UNIV CA EXT, HOLTVILLE
Submitted to: Journal of the Agricultural Association of China
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/1/1998
Publication Date: N/A
Interpretive Summary: We found since 1983 that soil application of aldicarb could reduce sweetpotato whiteflies on cotton in the southwestern United States. When silverleaf whiteflies became serious economic pest and sweetpotato whiteflies were hardly found since 1991, soil application of aldicarb was no more effective to control whiteflies. Only when silverleaf whitefly population density was low in mid- to late season in 1993, did soil application of aldicarb significantly increase cotton yield. We attribute this to the aldicarb effect on secondary pests, such as thrips and leafhoppers that occurred early in the cotton seasons.
Technical Abstract: Soil application of aldicarb reduced numbers of sweetpotato whitefly (SPW), Bemisia tabaci Gennadius, but not silverleaf whitefly (SLW), B. argentifolii Bellows and Perring, on upland cotton, Gossypium hirsutum L. Aldicarb-treated plants also had significantly fewer thrips, Frankliniella spp., leafhoppers, Empoasca spp., and damsel bugs, Nabis spp. early in the season, than untreated plants. Aldicarb-treated plants exhibited more vigorous plant growth than untreated plants. In mid- to late season from 21 June to 26 July in 1993 when SLW population density was low (8.0 nymphs/cm sq leaf disk for untreated plants) fewer SLW occurred on aldicarb-treated plants (4.4 nymphs/cm sq leaf disk). Lint yield increase was 42% as compared to untreated plants. In 1994, when SLW population density was high from mid- to late season from 15 June to 27 July (18.9 nymphs/cm sq leaf disk for untreated plants) the beneficial effect of aldicarb treatment was negated by the whitefly damage.