Pest Management Research Grants Awarded 2021

Back to Funded Pest Management Research Grants (2013 - present)

Project Summaries

Developing Best Management Practices for the Control of Diseases in Vegetable Transplant Greenhouses
Sponsor: University of California - Davis
Principal Investigator: Johanna Del Castillo
Funding total: $87,983

Over the last 20 years, vegetable production in California has shifted from planting fields with seeds to planting with transplants. Transplant greenhouses have emerged as a new type of production system in California with significant pest management needs and challenges. Recent surveys in cooperating vegetable greenhouses in the Sacramento and San Joaquin Valleys, indicate losses are caused by several diseases including black root rot (Thielaviopsis basicola), Botrytis leaf blight (B. cinerea), and Pythium root rot (Pythium spp.).

Currently there are no best management practices (BMPs) specifically tailored for this type of greenhouse production, making fungicides the dominate tool to control diseases, often unsuccessfully. To develop cultural strategies which can minimize dependency on chemicals requires an understanding of how pathogens are moving within production houses and how conditions are facilitating infection. A Hazard Analysis of Critical Control Points (HACCP) can be used to identify which stages of production harbor pathogens and promote disease development. For example, a baseline HACCP that was conducted at one facility identified re-used propagation trays and ineffective bench sanitation as means for pathogens to spread and infect transplant plugs. This information can be used to improve tray and bench sanitation practices. The goal of this project is to minimize the risk of pathogen infection and reduce pesticide use in vegetable transplant houses by accomplishing the project's objectives.

Media Contact: Johanna Del Castillo, Principal Investigator, 517-894 -7576,

Evaluation of an artificial sweetener as a potential bait toxicant and an insecticide synergist against German cockroaches, an important indoor pest of public health
Sponsor: University of California - Riverside
Principal Investigator: Chow-Yang Lee
Funding total: $110,938

The German cockroach, Blattella germanica, is a major indoor public health insect pest in the United States, especially in residential premises and food preparation establishments such as restaurants, food courts, food packaging factories, etc. The negative consequences of a German cockroach infestation includes mechanical transmission of pathogenic microorganisms, respiratory illness (allergy and asthma), and hygiene issues. Pest management professionals' control of this species has relied heavily on residual insecticide sprays and baits. Over-reliance and frequent usage of insecticides has led to the development of insecticide resistance in the German cockroach in the US, especially towards pyrethroids, phenyl pyrazole, and neonicotinoids, and an accumulation of pesticides in the indoor environment that could seriously impact human health.

Persistent environmental and health concerns such as effects on non-target organisms, bioaccumulation, and management challenges such as insecticide resistance has motivated the efforts to find alternative control strategies. Recently, there has been broad interest in investigating 'generally-recognized-as-safe' (GRAS) compounds such as essential oils and artificial sweeteners as insecticides for pest management. Artificial sweeteners are sweet-tasting additives found in beverages, food, drugs, and other products. Due to their low cost, accessibility, and minimal toxicity towards humans, artificial sweeteners are an appealing group of compounds when considering alternative treatment options. Ingestion of sweeteners by insects can lead to significant physiological effects such as mortality, decreased fecundity, and behavioral change. Recent work on sweetener toxicity revealed concentration-dependent mortality response to several polyols across multiple insect orders and other physiological effects.

The potential of using artificial sweeteners as a toxicant against German cockroaches has never been reported. Preliminary tests have shown that 10–20% sucralose, an artificial sweetener under trade name Splenda®, killed German cockroaches in choice and non-choice tests within 48 hours. This project's primary goal is to evaluate the potential of an artificial sweetener (sucralose) as a bait toxicant, and as an insecticide synergist for boric acid, for the effective management of insecticide-resistant German cockroaches. The second goal is to determine the possible mode of action(s) of sucralose in affecting the test insects’ susceptibility to insecticides.

Media Contact: Chow-Yang Lee, Principal Investigator, 951-827-2626,

Enhancing Virus Control in Lettuce and Melons by Optimizing Immunity Priming Approaches
Sponsor: University of California - Riverside
Principal Investigator: Kerry Mauck
Funding total: $216,967

The project addresses the challenging problem of virus infections in lettuce and melon production. Current virus management relies on vector control using high-risk insecticides, which are only marginally effective and pose risks to humans and the environment.

This project hypothesizes that virus impacts can be reduced by incorporating integrated pest management (IPM) practices that improve virus resistance and tolerance through immunity priming, and that integration of priming may allow for use of reduced risk insecticides in lower quantities.

This project will use greenhouse and field experiments to test IPM practices including immunity priming and communicate results to research peers and stakeholders through presentations to grower organizations and UCCE, and through articles for University of California IPM, California Agriculture magazine, and academic peer-reviewed venues.

Media Contact: Kerry Mauck, Principal Investigator, 951-827-5444,

Research toward the potential of reducing soil fumigation in California’s seedless watermelon using grafting and Trichoderma-containing biologics
Sponsor: University of California - Agriculture and Natural Resources
Principal Investigator: Zheng Wang
Funding total: $109,055

The goal of the project is to evaluate the potential of reducing soil fumigation in California's seedless watermelon production through the use of grafting and Trichoderma-based biologics. The proposed project will include field trials of grafted watermelons in 2022 and 2023 growing seasons under conventional California production conditions. In the field trials, Trichoderma-containing biofungicides will be applied to multi-pathogen resistant rootstock varieties at various times using multiple methods.

Numerous studies have demonstrated significant improvements in watermelon fruit yield and soil-borne fungal disease resistance or prevention through implementing grafted plants and microbial biologics. However, past research mainly tested the efficacy of single approach in research fields or greenhouses where environmental factors were strictly controlled and used a limited number of available watermelon rootstocks and lab-cultured isolates.

Today, with more watermelon rootstocks being on the market and heightened environmental requirements, this project seeks to understand both the single and combined effects of grafting and microbial biocontrol agents on the potential of reducing soil fumigation in environmentally-dynamic commercial watermelon fields while sustaining plant health and fruit yield. After examining the performances of various disease-resistant watermelon rootstocks and Trichoderma-containing biofungicide application practices, results will be shared with growers, academia, and other stakeholders of the site-specific feasibility and suitability of a given watermelon grafted combination and application practice of biocontrol agents in sustaining plant health and yield enhancement.

Media Contact: Zheng Wang, Principal Investigator, 209-525-6822,

For content questions, contact:
Jordan Weibel
1001 I Street, P.O. Box 4015
Sacramento, CA 95812-4015