New York case study: Biological control of otiorhynchus ligustici with native persistent entomopathogenic nematodes using a more classical approach

Abstract

Alfalfa snout beetle (ASB), Otiorhynchus ligustici (L.) (Coleoptera: Curculionidae) is a serious pest of alfalfa and clover production in Northern New York (NY), USA. Currently the infestation area covers >200,000 ha across nine NY counties and a small portion of Canada across the St Lawrence River from the NY infestation (Fig. 11.1). Within the infested area, entire fields of alfalfa and clover can be destroyed in a single year from root feeding by the larvae. This flightless parthenogenetic (clonal reproduction) European insect was introduced into the Port of Oswego, NY on shipping ballast between 1848 and 1896, when it was collected by Wickham (Claassen & Palm, 1935; Shields, Testa, Neumann, Flanders, & Schroeder, 2009). O. ligustici became an economic pest after alfalfa and clover were introduced into the area in the 1920s. In 1935, the infestation was reported to cover 235 ha, growing to 1,200 ha by 1941. By the 1970s, the infestation area had grown to 6,400 ha and by 2006, there were over 200,000 ha infested.