1998 ESA North Central Branch Meeting Abstract

68 PARASITOIDS OF THE BANDED SUNFLOWER MOTH, COCHYLIS HOSPES, IN CULTIVATED SUNFLOWER IN THE NORTHERN GREAT PLAINS. L. D. Charlet, USDA, ARS, Northern Crop Science Laboratory, Box 5677, University Station, Fargo, ND 58105-5677

The banded sunflower moth, Cochylis hospes Walsingham (Lepidoptera: Cochylidae), is a pest of cultivated sunflower throughout the northern and central Great Plains. Larvae consume pollen, disk flowers, and mature seeds in the sunflower head. Surveys for parasitoids of the banded sunflower moth were conducted during 1994 and 1995 in cultivated sunflower in North Dakota, South Dakota, and Minnesota. Mature larvae were recovered, subjected to cold treatment to break diapause, and held in a rearing room for emergence of parasitoids. The

following parasitoids were identified: Chelonus phaloniae Mason and Macrocentrus ancylivorus Rohwer (Braconidae), and Glypta prognatha Dasch and Trathala sp. (Ichneumonidae). The most abundant were G. prognatha, an internal larval parasitoid representing over 70% of the species recovered and C. phaloniae, an egg-larval internal parasitoid over 20%. Field studies in 1994 and 1995 showed that Chelonus phaloniae adults were active in the field for about 2 weeks beginning when plants were in the early bud stage and banded sunflower moth

oviposition had begun. Adult Glypta prognatha were present in the field plots from late July or early August to mid-August actively probing the disk flowers of heads for the presence of banded sunflower moth larvae. Parasitization of banded sunflower moth larvae was evaluated in plots seeded at three different planting dates in 1994 (11& 23 May, 3 June) and 1995 (23 May, 2 & 12 June). Parasitism averaged 29.7% in 1994 and 22.2% in 1995, with G. prognatha accounting for over 70% the species recovered. Parasitoids effectively attacked banded sunflower moth larvae in all dates, although the percentage of parasitism was slightly lower in the plots planted at the earliest date.

This paper will be presented on Monday.

Back to NCB Home Page