Minimizing insecticide use in snap beans using a risk-assessment decision guide

abstract

Improving management of European corn borer (ECB), Ostrinia nübilalis, in snap beans is considered a high priority by the New York snap bean industry. Predicting the risk for ECB attack in a snap bean field would help greatly in determining whether or not to use an insecticide and, if so, the number of applications. Additionally, control may be improved if we can identify the optimal timing for spraying. Efforts were initiated to address these issues through the development of a risk-assessment decision guide for ECB attack in snap bean fields and identification of optimal use of insecticides for ECB control.

submitted by

Nault, Brian A. | Associate Professor

issue being addressed

European corn borer (ECB), Ostrinia nübilalis, is the major insect pest of snap beans in the Northeast, the Midwest, and the mid-Atlantic states. The presence of ECB larvae within pods at harvest contaminates snap beans for processing. If the incidence of contamination is high, loads of beans may be rejected for processing. Consequently, the threshold for ECB-contaminated beans is very low. Although ECB does not attack all snap bean fields in New York, broad-spectrum insecticides are used preventatively one to two times during the season to protect the crop. Despite this conservative management approach, many ECB-infested beans are found each year. Consequently, there is concern about inadequate control of ECB with insecticides and unnecessary use of insecticides. To address this problem, a risk-assessment decision guide for ECB in snap bean was developed, and research on optimizing insecticide use was initiated. The ability to predict the risk of ECB attack in a snap bean field would make it much easier to decide whether or not to use an insecticide, and control may be improved if optimal timing of the insecticide spray is identified.

response

A risk-assessment decision guide for ECB in snap beans was developed after a comprehensive review of the literature. A risk level of ECB attack is assigned to a field based on three major criteria, including growth stage of the snap bean crop, level of moth activity, and growth stage of nearby corn fields (the preferred host of ECB). If the field is at low, medium, or high risk for ECB attack, the recommendation is not to spray, to spray one time, or to spray twice, respectively. A major crop consultant company in western New York that scouts a significant amount of the processing snap bean crop began using this guide in 2005.
Another major effort to address ECB management in snap beans has been to identify the most effective insecticide and its optimal use. A study last year at Cornell found no difference in the level of ECB control achieved by using acephate (an organophosphate) or a pyrethroid. Both products provided ECB control up to seven days after the application was made. Additional research is needed to identify the optimal timing of the insecticide to control ECB.

impact assessment

Adoption of the risk-assessment decision guide for ECB in snap beans is a major step toward improving ECB control and minimizing insecticide use. Last year, a major crop-consulting company adopted the use of this guide. Over the next couple of years, this guide may need to be refined based on our current and future research. At that time, the level of ECB control will be compared between fields in which the decision guide was used and those managed without the guide. This study will require collaboration among Cornell researchers, crop consultants, and the processor in order to measure the impact of this guide.

academic priority area

Environmental Sciences | CALS academic priority
Land-Grant Mission | CALS academic priority

topic description

Vegetable Entomology

has geographic focus

Canada | country
Minnesota | state
Massachusetts | state
Pennsylvania | state
Wisconsin | state
Connecticut | state
Illinois | state
New York State | state
New Hampshire | state
Iowa | state
Nebraska | state
Ohio | state
Indiana | state
Michigan | state
North Dakota | state
South Dakota | state
Vermont | state
Maine | state

funding source description

Hatch
New York Vegetable Growers Association

collaborators

Michael Gardinier
Abby Seaman
Richard Wildman

mission focus

extension/outreach | project type
research | project type