- Fruits: peaches, general tree fruits
- Farm Business Management: budgets/cost and returns
- Pest Management: biological control, integrated pest management
- Production Systems: holistic management, organic agriculture, transitioning to organic
Conservation and augmentation of diverse biocontrol elements within an orchard system can be critical to sustainability. Orchard crops are attacked by a complex of wood-boring insects. Of particular concern for stone fruits in the Southeastern US are the peachtree borer (PTB), Synanthedon exitiosa, and the lesser peachtree borer (LPTB), Synanthedon pictipes. PTB is a root pest, whereas the LPTB is an aboveground pest, boring into the tree’s trunk and limbs. These pests are controlled with broad spectrum chemical insecticides. The continual use of these chemicals can have a profound negative impact on the complex of beneficial natural enemies in cropping systems. Clearly, effective alternative pest management strategies are needed for these pests. Our research has indicated substantial promise for a sustainable biocontrol solution, i.e., the use of entomopathogenic (insect-killing) nematodes (EPNs). In small field plots, we demonstrated that the nematode Steinernema carpocapsae has potential to control peachtree borer damage at levels similar to that of recommended chemical insecticide treatments, and that applications costs are likely to be highly economical. The primary challenge that remains is to determine how best to apply the nematodes at a commercial scale so growers can adopt the practice. For lesser peachtree borer, given that the insect is an aboveground pest, and that entomopathogenic nematodes are highly sensitive to desiccation and UV radiation, the primary hurdle is protection from environmental stress. Indeed, we have demonstrated that S. carpocapsae can cause high levels of lesser peachtree borer control, but only when the nematodes are protected from environmental stress. The primary challenge remaining is to determine the optimum protective formulation to achieve efficacy. Implementation of entomopathogenic nematodes as a biocontrol strategy for these borer pests (and the concurrent reduction in chemical inputs) may enhance the overall complex of beneficial natural enemies in the orchard system. However, there is a dearth of knowledge regarding the specific impact of biocontrol tactics on overall natural enemy systems. Therefore, we will assess the impact of the new biocontrol tactics on the broad array of indigenous natural enemies (e.g., insect predators and pathogens). Thus, our overall goal is to tackle the primary remaining challenges to implementing entomopathogenic nematodes as a biocontrol tactic for borer pests, and to assess the broader impact of this biocontrol strategy on the system. Specifically, our objectives are to I) Determine the optimum method of applying entomopathogenic nematodes for control of PTB, II) Determine the optimum entomopathogenic nematode formulation for control of LPTB, and III) Assess the impact of biocontrol applications on natural enemy populations. This project promises to achieve grower level implementation of a novel biocontrol solution in peaches and thereby substantially move the system toward sustainability. Methodology developed will be applicable to other cropping systems as well. Based on the expertise of our project team (scientists and growers), and the research we have conducted thus far, the likelihood of the project’s success is high indeed.
Project objectives from proposal:
Our overall goal is to develop a sustainable management system for southeastern peaches. In this project we will tackle the two primary remaining research challenges to implementing entomopathogenic nematodes as a biocontrol agent for borer pests in peach; additionally, we will investigate the impact of the novel control tactics on the system. Specifically, our objectives are:
I) To determine the optimum method of applying entomopathogenic nematodes for control of peachtree borer (on a commercial scale).
II) To determine the optimum entomopathogenic nematode formulation for control of lesser peachtree borer.
III) Assess the impact of biocontrol applications on natural enemy systems.