Banded Cucumber Beetle (Diabrotica balteata LeC.) Injury during Sweetpotato Development

Abstract

Banded cucumber beetle (Diabrotica balteata LeC.) larvae can cause significant injury to the sweetpotato [Ipomoea batatas (L.) Lam.] by boring small holes in the storage root. Often, these holes expand with development to produce crater-like scars. The objective of this research was to characterize the effects of Diabrotica injury to storage roots by simulating the injury through development. Deep (i.e., penetrating the vascular cambium) and shallow (i.e., not penetrating the vascular cambium) injuries were inflicted at 10-day intervals on `Beauregard' sweetpotato commencing 35 days after transplanting (DAT) through 85 DAT in 1996 and 1997. Visual evaluation indicated significant healing of deep injury through 55 DAT, with the diagnostic cratered appearance more prevalent on storage roots injured at 35 and 45 DAT. Moreover, deep injury in early development (35, 45 DAT) significantly expanded in diameter and depth, reducing marketable yield. Significant healing of shallow injury was observed through 75 DAT. The results of this research can be used by growers and researchers to assess the stage of development in which Diabrotica injury occurred.