Skip to main content
ARS Home » Midwest Area » Ames, Iowa » Corn Insects and Crop Genetics Research » Research » Publications at this Location » Publication #90037
Title: EFFECTS OF FIELD EDGE TYPE ON NATURAL ENEMIES OF THE EUROPEAN CORN BORER, OSTRINIA NUBILALIS (LEPIDOPTERA: CRAMBIDAE)

Author
item Bruck, Denny
item Lewis, Leslie

Submitted to: Journal of Agricultural and Urban Entomology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/27/1999
Publication Date: N/A
Citation: N/A

Interpretive Summary: The European corn borer is one of the most destructive insects of field corn in the United States. Damage caused by the corn borer ranks second annually only to the corn rootworm complex. The use of habitat conservation and manipulation for use as refuge area for natural enemies is an active area of research. This research tested the effect of three different field edge type habitats as refuge areas for corn borer parasitoids, and also the effect of these habitats on the prevalence of two insect pathogens. Corn borer larvae were collected from plants bordering each edge type following both corn borer generations in each of two years. Edge type had no direct influence on either of the pathogens investigated. The percentage of larvae parasitized was significantly greater during second generation in one of the years studied along the wooded edge type. There was however a trend of increasing larval parasitism along the wooded edge type throughout the growing season. An antagonistic interaction was noted between one of the pathogens and the larval parasitoid which may have masked some of the positive affect that the more diverse edge types were hypothesized to have on the parasitoid. The results of this research show that growers and IPM practitioners may benefit from an increase in parasitoid numbers resulting from the conservation or manipulation of existing or incorporated field edge habitats which will reduce the need for chemical insecticides.

Technical Abstract: The European corn borer (Ostrinia nubilalis) (Hubner) is one of the most destructive insects of field corn in the United States. Damage caused by the corn borer ranks second annually only to the corn rootworm complex. The use of habitat conservation and manipulation for use as refuge area for natural enemies is an active area of research. This research tested the effect of three different field edge type habitats: 1) herbaceous, 2) intermediate, and 3) wooded as refuge areas for corn borer parasitoids. Also studied was the effect of the three edge type habitats on the prevalence of the entomopathogens Beauveria bassiana (Balsamo) Vuillemin and Nosema pyrausta (Paillot). Corn borer larvae were collected from plants in the first twenty rows of corn bordering each edge type following both corn borer generations in each of two years. Edge type had no direct influence on either of the pathogens investigated. The percentage of larvae parasitized by the primary parasitoid, Macrocentrus grandii Goidanich, was significantly greater during second generation in one of the years studied along the wooded edge type. There was however a trend of increasing larval parasitism along the wooded edge throughout the growing season. An antagonistic interaction was noted between N. pyrausta and M. grandii which may have masked some of the positive affect that the diverse edge types were hypothesized to have on M. grandii. The results of this research show that growers and IPM practitioners may benefit from an increase in parasitoid numbers resulting from the conservation or manipulation of existing or incorporated field edge habitats.