Development and Implementation of Ecologically Sound, System-based Tactics for Managing Pests and Insect-vectored Diseases in Cucurbit Production in the Southeast

View the project final report

Commodities

• Vegetables: cucurbits

Practices

• Pest Management: biological control, biorational pesticides, cultural control, disease vectors, integrated pest management

This research proposal involving a multidisciplinary team of researchers, extension specialists, and participating vegetable producers from two states in the South (Alabama and Florida) was designed to address the major production challenges identified by local cucurbit growers. Cucurbits, in particular, squash, cucumbers, watermelons, and pumpkins, are produced as high-value crops in Alabama, Florida, and other parts of the southern U.S. However, outbreaks of viral diseases and insect vectors (aphids and whiteflies) have become chronic and persistent threats to the profitability of cucurbit production in the region. The goal of this project is to assist southern cucurbit growers in combating these key pest problems by developing and implementing effective, system-based Integrated Pest Management (IPM) tactics, including row-cover (protective barriers) (Objective 1), plant defense system stimulating soil microbes, habitat manipulation through biologically active ground cover plants, and biocontrol agents (Objective 2). The on-farm integration and evaluation of the economic feasibility of adopting the tactics proposed in Objective 3 will help understand how individual tactics interact and complement each other in a complex agroecosystem. A comprehensive outreach plan in Objective 4 will facilitate the program's implementation through training, education, and technology transfer.

The results of a multi-year field trial, repeated on-farm in 2020, suggest that the row-cover strategy can provide complete protection to squash against insect pests and diseases. The row-cover strategy could be a potential, economically feasible, pest management tactic, especially for organic or naturally grown cucurbit farmers who lack synthetic pesticides. Field studies were conducted over multiple cropping seasons at a research station and at a commercial organic vegetable farm in Florida to evaluate the efficacy of biological control agents and companion plantings for managing aphids and whiteflies in squash. The results showed that augmentative releases of the predatory mite, Amblyseius swirskii, can lower the incidence of adult whiteflies. Similarly, sweet alyssum as companion plants resulted in a high number of natural enemies (Orius spp., syrphid, and long-legged flies) on the sweet alyssum flowers. As part of the Extension Vegetable IPM program, this project provided direct consultation support to producers (reactive activities) with on-farm visits, telephonic, and email conversations. This project also offered planned events for high-impact training to both beginning and experienced vegetable producers (activity summary in the next section). 

The specific objectives of this project were to:

1. Evaluate a protective barrier as a mechanical tool to manage insect vectors of cucurbit diseases.
2. Evaluate environmentally sustainable tactics for managing aphids and whiteflies on cucurbits, including plant defense-boosters, habitat manipulation through biologically active ground cover plants, and biocontrol agents.
3. On-farm integration of effective tactics developed in Objectives 1 & 2 to develop an IPM program for cucurbit production.
4. Develop a participatory implementation plan of research results for cucurbit vegetable growers using a multilevel extension program, communication, and evaluation plan.