Improved management of striped cucumber beetle , Acalymma vittaum (F.) (Coleoptera: Chrysomelidae) by using a squash trap crop and a polyculture of cucumber and tomato.

Improved management of striped cucumber beetle , Acalymma vittaum (F.) (Coleoptera: Chrysomelidae) by using a squash trap crop and a polyculture of cucumber and tomato.

Summary

A comparison of the effects of different organic and sustainable non-crop vegetation and soil management techniques such as trap crops on striped cucumber beetle population dynamics. A Blue Hubbard trap crop provided some early season protection, but the trap crop effect broke down late in the season, and was not as effective a control method as floating row covers. Including a tomato intercrop or adding a cucurbitacin spray or a pyganic spray to the trap crop failed to improve the trap crop’s effectiveness. Data were gathered on MSU campus at the Student Organic and Horticulture farms.

Objectives/Performance Targets

Intermediate-term: Catalyzing co-learning, knowledge and innovation among organic and transitioning farmers, and improving the sustainability and profitability of cucumber production in the Midwest.

Short-term: A sustainable pest management plan for cucumber beetle using improved trap crop effects, adding to scientific and outreach literature, and generating informed discussion about sustainable approaches to agriculture among growers.

Accomplishments/Milestones

Two years of data have been collected in 2006 and 2007 and statistically analyzed. Preliminary results from the first year were presented at the 2006 National ESA meeting as well as the 2006 and 2007 Michigan Ag Expo. A website for growers interested in using non-crop vegetation such as trap crops and cover crops to improve their vegetable production practices has been constructed and is online (available here: http://www.ipm.msu.edu/noncrop/noncrop.htm). A masters thesis, “Evaluating organic-compliant management strategies for striped cucumber beetle in cucumbers,” was defended on August 21st 2008, and has been published. A journal article publication based on this work are also underway.

Key Findings So Far:
• The use of a Blue Hubbard trap crop provides some, but not extremely high, protection against cucumber beetles early in the growing season as compared with cucumber in monoculture. However, the level of protection was not high enough for this technique to be used as a stand alone control measure. In 2007, mixing two trap crop cultivars in a row, one Blue Hubbard and another one less attractive, had benefits in extending the trap crop attractiveness longer in the season.

• Alternating tomato and cucumber rows (the polyculture) did not provide protection against the beetles in a way that was cumulative with the trap crop effect.

• A floating row cover provided the best protection from cucumber beetles and improved
yield and fruit quality.

• The addition of a cucurbitacin spray to the Blue Hubbard trap crop did not significantly increase its effectiveness as a trap crop for striped cucumber beetles.

• Integrating a mixed rye-hairy vetch cover crop into the production system improved nutrient provisioning and cucumber and tomato yield.

• The benefit of compost applications was maximized only in systems with hairy vetch (legume) cover crop.

• The addition of a Pyganic spray to the trap crop acted as an irritant, decreasing the trap crop effect, killing some beetles, but also repelling others from the trap crop.

Impacts and Contributions/Outcomes

Our presentation at the ESA annual meeting and presence at the 2006 and 2007 Michigan Ag Expo has allowed us to speak with growers and share some of our early findings. We have no hard data on yield increases or dollars saved per acre. The major obstacle here is that the control methods tested were found to provide little to no late season protection, allowing beetles to scar the mature fruit and reduce marketable yield even if total yield has been increased. While we have been unable to implement, test, and record a much needed method for late season organic protection of cucumbers from striped cucumber beetle, we have contributed to the body of knowledge surrounding cucumber beetle behavior and management, particularly in the early to mid growing season, and offered up potential solutions to late season protection that will require further research. Our presentations and website have provided Michigan growers with useful and practical information regarding sustainable agricultural practices. This work is aimed at encouraging organic and sustainable agricultural practices such as cover crops and trap cropping throughout Michigan.

Collaborators: