Submitted to: Journal of Agricultural and Urban Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/27/2006
Publication Date: 1/11/2006
Citation: Canhilal, R., Carner, G.R., Griffin, R.P., Jackson, D.M., Alverson, D.R. 2006. A Life History of the Squash Vine Borer, Melittia Cucurbitae (harris) (lepidoptera: sesiidae) in South Carolina. Journal of Agricultural and Urban Entomology. 23:1-6.
Interpretive Summary: The life history of the squash vine borer, a destructive pest of squash and pumpkins, was investigated in South Carolina. Life history information could potentially provide useful information for the development of pest management techniques. Duration of life stages, numbers of offspring, field distribution, and mortality rates were determined. Eggs hatched in 8-11 days, and development of larvae and pupae were 24-27 days and 27-29 days, respectively. The total development time from egg to adult was 62-65 days. Longevity of adults in the field was 4-5 days for females and 3 days for males. Females laid an average of 40 eggs. Squash vine borer has a prolonged emergence pattern as determined by pheromone traps that were maintained at Clemson and Charleston. Squash vine borer has two overlapping generations per year in South Carolina with the first generation beginning in May. Adults remain active until September at Clemson and until October at Charleston. Populations peak in mid summer. Moths were observed depositing eggs on the leaf stalks, on upper and lower sides of the leaves, on fruit buds, but mostly on the bottom part of the main stem. Larval activity continued until mid to late October when larae made cocoons in the soil to overwinter.
Technical Abstract: The life history of the squash vine borer (Lepidoptera: Sesiidae) was investigated in South Carolina. Duration of life stages, numbers of progeny, and mortality rates for SVB were determined in cages held at 25 plus minus 2C, 65-70% humidity and a photoperiod of 16:8 (L:D) h in a rearing room, and outside under natural environmental conditions (May 14-July 24, 1998). These biological parameters were used to construct a life table for SVB. Eggs hatched, on average, in 10.5 and 8.2 d in the rearing room and outside cages, respectively. Larval and pupal development times averaged 24.4 and 27.5 d in the rearing room, and 26.6 and 29.3 d in outside cages, respectively. Average total development time for immature stages, from egg to adult, was 62.1 d in the rearing room and 65 d in outside cages. Longevity of females averaged 5.2 and 3.9 d for the rearing room and the outside cages, respectively. Males lived, on average 3.1 and 3.0 d in the rearing room and the outside cages. Preoviposition time of females averaged about one day, and females continued to lay eggs for 3 d in the rearing room and 1.9 d in the outside cages. Fecundity averaged 42 and 40.5 eggs/female for the rearing room and the outside cages, respectively. Intrinsic rate of increase (rm) was 0.035 for the rearing room and 0.029 for outside cages. Reproductive rate (Ro) was calculated to be 9.8 and 7 daughters per female for rearing room and outside cages, respectively. The mean period from birth of parents to birth of offspring (T) was calculated to be 65.2 d for the rearing room and 67.3 d for outside cages. Pheromone trap data from 2 yrs and 2 locations indicated that SVB has 2 overlapping generations per year and a prolonged emergence pattern in South Carolina. The moths of the first generation emerged around mid-May and adults emerged continuously about 4.0-4.5 months. Adult population size increases at the end of July, and continues through the beginning of September. Larval activity continued until mid to late October when larvae made cocoons in the soil 2.5 (an inch) or 5 (two inches) cm deep to overwinter as larvae.