Effects of the fall environment on the boll weevil in northeast Mississippi.

Abstract

Limited studies of the preoviposition and developmental periods of the boll weevil, Anthonomus grandis Boheman, were made in the field in the fall of 1964. More extensive studies were made with simulated fall temperatures and day lengths in the laboratory during the winter 1964–65. Both field and laboratory data indicated that with the cooler temperatures of the fall, the preoviposition period of emerging boll weevils was generally longer than that of weevils emerging earlier in the season, though some individual females had a preoviposition period shorter than 1 week until night temperatures dropped to 50°F or lower. Each developmental stage of the boll weevil was considerably longer, with cooler temperatures and shorter photoperiods. The total developmental period from egg to adult was as short as 24 days when eggs were laid in squares early in September and as long as 60 days when eggs were laid in bolls in mid-September. The time to emergence of adult boll weevils from eggs deposited on a given date in the fall showed a wide range. The data indicated that an egg laid on or after October 1 would not contribute to the overwintered population of weevils.