Recent bean leaf beetle and bean pod mottle virus research

Soybean growers face a dilemma when considering management options for bean leaf beetles and bean pod mottle virus. Rayda Krell recently completed a research program at Iowa State University that focused on immediate solutions for this pest problem. This article summarizes her research from which we suggest some short-term management options

Revisiting an integrated approach to bean leaf beetle and bean pod mottle virus management

This article originally appeared in the 2005 ICM newsletter. However, the significance of the bean leaf beetle and bean pod mottle virus has not diminished in recent years. There is still the potential of economic damage from either or both pests. We have recently completed a three-year study that examines the complex issues of managing these two pests, but the data are still being analyzed. We also have identified potential field tolerance to virus disease. Growers are encouraged to query seed dealers regarding tolerance of varieties to virus disease. Ultimately, this will likely be the best management tool for disease control. In the meantime, we give you our best recommendations as we understand the situation in Iowa

Seed treatments in soybean: Managing bean leaf beetles

To date, our recommendation for the chemical control of bean leaf beetles and bean pod mottle virus has been for an early and a mid-season application of a pyrethroid insecticide (e.g., Asana®, Mustang®, or Warrior®). These insecticide applications should be timed such that fields are treated as soon as bean leaf beetles are first detected in the field (the early-season application) and again when the first generation emerges in early July (the mid-season application). These applications have been shown to improve yield and seed quality under high disease and beetle pressure

Evaluation of Management Tactics for Bean Leaf Beetles and Bean Pod Mottle Virus in Soybean

An increase in bean leaf beetles has caused an increase in bean pod mottle virus - a yield robbing plant pathogen in Iowa soybeans. The incidence of bean pod mottle virus is often positively correlated with bean leaf beetle populations. For example, the greatest increase in bean pod mottle virus infection occurs after the first generation of bean leaf beetles reaches peak population density (late July). However, soybeans are most affected when soybeans are infected as seedlings

Evaluation of Management Strategies for Bean Leaf Beetles (Coleoptera: Chrysomelidae) and Bean Pod Mottle Virus (Comoviridae) in Soybean

Cerotoma trifurcata Förster (Coleoptera: Chrysomelidae) and Bean pod mottle virus (Comoviridae) (BPMV) both can reduce yield and seed quality of soybean, Glycine max (L.) Merr. Field experiments were conducted to evaluate the effects of systemic, seed-applied, and foliar-applied insecticides for the management of this pest complex at three locations in central, northeastern, and northwestern Iowa during 2002-2004. Seed-applied insecticide was evaluated according to a currently recommended management program for Iowa (i.e., insecticide applications that target emerging overwintered beetles, F0, and the first seasonal generation, F1). The experimental treatments included seed-applied (thiamethoxam, 0.3-0.5 g [AI] kg-1] or clothianidin, 47.32 ml [AI] kg-1) and foliarapplied (λ-cyhalothrin, 16.83-28.05 g [AI] ha-1) or esfenvalerate (43.74-54.69 g [AI] ha-1) insecticides. Applications of the foliar insecticides were timed to target F0, F1 or both F0 and F1 populations of C. trifurcata. Our results confirm that insecticides timed at F0 and F1 populations of C. trifurcata can reduce vector populations throughout the growing season, provide limited reduction in virus incidence, and improve both yield and seed coat color. Furthermore, seed-applied insecticides may be the more reliable option for an F0-targeted insecticide if used within this management strategy. An F0-targeted insecticide by itself only gave a yield improvement in one out of eight location-years. However, by adding an F1-targeted insecticide, there was a yield gain of 1.42-1.67 quintal ha-1, based on contrast comparisons at three location-years

Management of Bean Leaf Beetles and Bean Pod Mottle Virus: A Summary of Current and Future Research

In 2002, the bean leaf beetle, Cerotoma trifurcata (Forster), population reached the highest level recorded in 14 years (Fig. 1). The bean leaf beetle is now considered the most frequent insect pest of Iowa soybean, and concern over this pest is greater because it transmits a soybean virus, Bean pod mottle virus (BPMV). Bean leaf beetle management recently has become more complicated because of this insect\u27s association with BPMV, therefore, it is important to understand the life cycle of the beetle and its relation to BPMV before management decisions are made

Bean leaf beetle and bean pod mottle virus management: An integrated approach

Growing soybean in Iowa has become a more complicated task in recent years. One early-season dilemma for growers is which management plan to implement for a pest complex of bean leaf beetles and bean pod mottle virus. We have developed a decision guide for the management of these two pests. The decision guide is based on new research and presents a grower with two management plans: one for managing both the beetle and the virus, or one for managing only the beetle. Ultimately, these management guidelines require knowledge of the soybean field\u27s pest history