ABSTRACT
Laboratory experiments were performed in fall/winter 1997 in which diapause-conditioned boll weevils, Anthonomus grandis grandis Boheman, were subjected to freezing temperatures within containers submerged in a cold circulation bath and held for one to eight hours. Containers were either empty, or filled with dry or moist leaf litter. Results show that temperature, duration of exposure, and litter, as well as all interactions were significant factors of boll weevil mortality. Mortality increased with temperature reduction and exposure time. The presence of dry litter significantly improved weevil survival over those in empty containers at -10.0 and -12.5oC, and over those in moist litter at -5.0 to -12.5oC. Over 70% of weevils were able to survive temperatures of -2.5oC for eight hours, in either moist or dry litter, while high (>75%) mortality occurred at -10oC or colder temperatures in moist litter, even for short (1 hour) exposures.
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