Triple threat: combining multiple IPM tactics to improve thrips control in peppers

Commodities

Practices

Non-chemical pest management offers a variety of positive impacts on specialty crop production. In the Midwest, especially Ohio, where pepper production is economically significant and faces multiple pest threats, of which thrips are a prominent one, exploring alternative management methods is crucial. Current thrips management relies heavily on calendarized insecticide programs leading to excessive usage, fostering insecticide resistance, and raising production costs. Insect natural enemies provide a biological control alternative for managing insect pests in agricultural ecosystems. To date, beneficial organisms are frequently undervalued within pepper production, and, like the targeted pests, they are directly impacted by calendarized insecticide programs, causing a decline in their natural populations within the agroecosystem (Srivastava et al., 2014).

Previous research has identified that Integrated Pest Management (IPM) approaches, such as threshold-based insecticide applications, the integration of differently colored plastic mulches, and reduced fertility rates offer alternatives for thrips management compared to calendar-based insecticide programs. Thus, we propose to examine the impact of these management practices in a factorial experiment. We will examine the combined effect of different insecticide programs (weekly, threshold-based, untreated control) paired with different mulch types (reflective, black, and bare ground) and fertility regimes (grower fertilizer program, sufficiency-based fertilizer program, and an unfertilized control) first in a controlled trial and then followed by on-farm replications to evaluate most effective treatment combinations under more realistic production conditions.

The results of our study will be used to develop an IPM program that provides effective alternatives for controlling thrips in peppers. This program will reduce the dependence on insecticide, thereby promoting the natural enemy community responsible for natural pest control. We also anticipate reducing fertilizer rates which will slow pest populations and reduce fertility-associated pollution. The proposed IPM program is expected to help growers save on production costs, slow the onset of insecticide resistance, and promote more resilient agroecosystems better equipped to combat pest through synergies with other IPM tactics like biological control. Additionally, 3-D extension models and fact sheets will enhance grower’s abilities to identify thrips and the natural enemies associated with their biological control aimed at expanding their knowledge of these biological systems to encourage their conservation. We plan to disseminate the project's findings in the Northcentral region through presentations at grower/scientific conferences, as well as creating content for agricultural extension.

References:

M. Srivastava, et al. Fla. Entomol. 97(2), 337-348 (2014)

United States. U.S. National Agricultural Statistics Service. https://www.nas.usda.gov/ (2022)

My primary goal is to evaluate an efficient yet cost-effective alternative pest management program to control thrips in pepper production. We expect that an alternative pest management program that features reduced fertility regimes, reflective mulch, and threshold-based insecticide applications will confer greatest production outcomes; increased marketable yields, decreased input costs, and boosted natural enemy communities. As a result of this project, I expect the following outcomes:

Outcome 1: Grower’s knowledge of thrips pest management practices (using pest action thresholds, decreasing fertilizer rates, using reflective mulches) will increase as compared to before the project.

Outcome 2: Growers will increase their use of threshold-based insecticide programs as compared to before the project.

Outcome 3: Growers will reduce their rates of fertilizers as compared to before the project.

Outcome 4: Growers will have an increased appreciation for arthropod-mediated ecosystem services (e.g., biocontrol) that are disturbed by insecticides.

Outcome 5: Growers will improve their ability to scout for thrips, thrips damage and their natural enemies. This will be achieved with 3-D models, and laminated fact sheets elaborated for extension purposes (for better details on this outcome, see objective 3 in the materials and methods section below).

Outcome 6: There will be an increase in growers’ willingness to adopt the alternative pest management program, or at the very least in integrating certain facets of it into their farming practices.

Ultimately, these outcomes will be measured as changes in knowledge and adoption of pest management practices which are described below in the ‘Evaluation Plan’.