Browsing Cotton Report 1989 by Authors
Late Season Boll Weevil Infestations and Survival in a Cotton Bolls in ArizonaHenneberry, T. J.; Meng T. Jr.; Bariola, L. A.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)Studies were conducted in Phoenix AZ, to determine the development of boll weevil, Anthonomus grandis Boheman, infestations in late - season cotton bolls, the pattern of boll weevil emergence, and survival /mortality in the bolls. Boll weevils emerged from bolls buried in moist vermiculite over a period of 232 to 239 days, from 29 January to 2 August. Higher percentages of emergence and lowest mortality in bolls occurred in bolls collected in November as compared to bolls collected in December. Few boll weevils emerged from bolls held under dry conditions in an outdoor insectary for 174 days. However, an average of 16% of the weevils were found alive in the dry bolls in late May.
Yield, Earliness, and Response to Pink Bollworm of a Resistant Line and a Standard Cultivar Treated with Ethephon and UntreatedWilson, F. D.; Flint, H. M.; Bariola, L. A.; Silvertooth, Jeff; Isbell, Joan (College of Agriculture, University of Arizona (Tucson, AZ), 1989-03)An experimental cotton line, WC-12NL (nectariless, okra leaf early maturing) was compared in large plot (2-acre) replicated experiments with a standard cultivar, 'Deltapine 61' ( nectaried, regular leaf shape, full-season), for 3 seasons, 1986 to 1984 at 2 locations, Maricopa, AZ and Brawley, CA. Ethephon ("Prep") was applied to half of each plot when the crop was ca. 60% open. Pink bollworm (PBW) eggs were counted twice weekly on bolls and the 2 cottons were sprayed separately for PBW control when the egg infestation on bolls reached the action level. Seed cotton was harvested weekly as soon as bolls started to open. Over the 3 seasons and 2 locations, WC 12NL yielded 12% more total lint, 43% more cumulative lint at the third harvest date, and required only 59% as much insecticide to control PBW as did Deltapine 61.