Skip to main content
ARS Home » Plains Area » Fargo, North Dakota » Edward T. Schafer Agricultural Research Center » Sunflower and Plant Biology Research » Research » Publications at this Location » Publication #137339
Title: INCIDENCE OF SUNFLOWER BEETLE (COLEOPTERA: CHRYSOMELIDAE) AND PARASITISM OF ITS LARVAE BY MYIOPHARUS MACELLUS (DIPTERA: TACHINIDAE) IN NATIVE SUNFLOWERS IN NORTH DAKOTA AND MINNESOTA

Author
item CHARLET, LAURENCE

Submitted to: Journal of Kansas Entomological Society
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/4/2003
Publication Date: 6/25/2003
Citation: CHARLET, L.D. INCIDENCE OF SUNFLOWER BEETLE (COLEOPTERA: CHRYSOMELIDAE) AND PARASITISM OF ITS LARVAE BY MYIOPHARUS MACELLUS (DIPTERA: TACHINIDAE) IN NATIVE SUNFLOWERS IN NORTH DAKOTA AND MINNESOTA. 2003. JOURNAL OF THE KANSAS ENTOMOLOGICAL SOCIETY. V. 76 (3). P. 436-441.

Interpretive Summary: Sunflower (Helianthus spp.) is native to North America which allows for the movement of pests, which have coevolved on wild sunflowers, into commercial fields. The sunflower beetle is the most important defoliating pest of sunflower. The objectives of this study were to investigate native species of sunflower in North Dakota and Minnesota to determine sunflower beetle incidence and their parasites. Six species of native sunflowers were sampled at 16 locations in eastern North Dakota, in 1995, and 25 sites in both eastern North Dakota and western Minnesota, in 1996. Results showed that sunflower beetles occurred on all species. The incidence of beetle larvae in 1995 was over 60% and in 1996 was 100% in the collection sites. Although limited to one collection, only one beetle larvae was recovered from plants of H. pauciflorus. Additional sampling would be needed to determine if the low beetle numbers were due to some form of resistance. There were no species of larval parasites found during the study. The only species recovered was the tachinid fly parasite, M. macellus, which parasitized up to 100% of the sunflower beetle larvae at the sites sampled. This parasite attacked beetle larvae in all species of native sunflowers except H. pauciflorus. The rates of parasitism were generally equal to or higher than that found in cultivated fields in North Dakota or Minnesota. Subsequent collections to include other species of native sunflowers and to expand the sampling into other states and locations in the northern and central Plains may result in additional natural enemies to augment the biological control of the sunflower beetle in cultivated sunflower.

Technical Abstract: Sunflower (Helianthus annuus L.) is native to North America which allows for the movement of pests, which have coevolved on wild sunflowers, into commercial plantings. The sunflower beetle, Zygogramma exclamationis (Fitch), is the most important defoliating pest of cultivated sunflower. The objectives of this study were to investigate native species of sunflower in North Dakota and Minnesota to determine sunflower beetle incidence and the indigenous larval parasitoid fauna. Six species of native sunflowers were sampled at 16 locations in eastern North Dakota, in 1995, and 25 sites in both eastern North Dakota and western Minnesota, in 1996. Larvae were dissected in the laboratory to determine parasitoids species and parasitization rates. Results showed that sunflower beetle occurred on all species. The incidence of beetle larvae in 1995 was over 60% and in 1996 was 100% in the collection sites. Although limited to one collection, only one beetle larvae was recovered from plants of H. pauciflorus. Additional sampling would be needed to determine if the low beetle numbers were due to some form of resistance. Dissection of beetle larvae from the different collection sites yielded no new records of larval parasitoids. The only species recovered was the tachinid, M. macellus, which parasitized up to 100% of the sunflower beetle larvae at the sites sampled. This fly parasitoid attacked beetle larvae in all species of native sunflowers except H. pauciflorus. The rates of parasitization of sunflower beetle larvae from the different species of sunflower were generally equal to or higher than that found in cultivated fields in North Dakota or Minnesota. Subsequent collections to include other species of Helianthus and to expand the sampling into other states and locations in the northern and central Plains may result in additional natural enemies to augment the biological control of the sunflower beetle in cultivated sunflower.