Impact of Western Bean Cutworm (Lepidoptera: Noctuidae) Infestation and Insecticide Treatments on Damage and Marketable Yield of Michigan Dry Beans

Larval movement of Anticarsia gemmatalis (Lepidoptera: Erebidae) on vegetative and reproductive stage non-Bt soybean

“…A noticeable characteristic during the evaluation was that we observed higher larval movement to the middle and lower plant section and to the abaxial leaf position during the warm hours of the day. Similar behavior was also reported for Striacosta albicosta (Smith) (Lepidoptera: Noctuidae) in dry beans 40 . At 14 days after hatch (DAH), most 4 th instars larvae were found on the soil surface.…”

Contribution of larvae developing on corn and dry beans to the adult population of western bean cutworm in Michigan

“…Previously, extension biologists have observed a preference for corn over dry beans when the corn has yet to tassel at the start of moth flight A third explanation may be that larvae have a low success rate developing and overwintering under dry bean cultivation due to various unknown environmental factors. For example, soil type has been suggested to affect prepupae development and survivability in previous laboratory studies and foliar insecticides tend to be used more frequently in dry beans than in corn (Montezano et al 2019, Difonzo et al 2015). While we are unable to provide a precise reason for our observed results, they still suggest that corn fields act as an efficient supply of adult moths for the western bean cutworm, maintaining successful mating populations in the region and perpetuating the damage on dry beans the subsequent growing season.…”

“…In corn, feeding with an infestation of one larva per ear can result in a loss of four bushels per acre, with large infestations reducing the yield by 30 to 40%, while in beans the yield is reduced by 8 to 10% (Peairs 2014). Additionally, feeding provides entry for molds and other plant pathogens, increasing the risk of diseases and mycotoxin contamination (Rice and Dorhout 2006, Seymour et al 2010, Difonzo et al 2015. Historically a pest of the western Great Plains region of the United States, over the past quarter of a century it has expanded eastward and is now established in at least twenty-five states and four Canadian provinces (Hoerner 1948, Hagen 1962, Jeschke 2018.…”

“…Management of the western bean cutworm varies depending on the host and time of the growing season. In beans, foliar insecticide applications are the main mechanism of control, with pyrethroid applications showing excellent control of the western bean cutworm (Difonzo et al 2015). However, application of foliar insecticides requires labor intensive scouting practices which are challenging due to the egg masses being located on the underside of the leaves and the nocturnal habits of the larvae.…”

“…Another scouting method requires the use of pheromone traps to capture adult moths to determine when insecticide treatment is needed. Unfortunately, established insecticide application thresholds have been unreliable in the Great Lakes region where significant bean and corn damage are observed when trap numbers are low, compared to those observed in native western regions such as the state of Nebraska (Difonzo et al 2015).…”