Improving sustainability of solanaceous crop farming through increased effectiveness of biocontrol methods against Fusarium diseases

Commodities

Practices

The purpose of this project is to increase the sustainability of specialty crop farming by reducing the incidence of an important food security issue such as Fusarium through identification and management with effective biocontrol agents. The hypothesis is that the molecular identification of local Fusarium species/strains, dual confrontation assays to assess biocontrol effectiveness of commercial Trichoderma species/strains, and its verification/demonstration in on-farm studies will facilitate adoption of effective management strategies that improve the sustainability of producing solanaceous crops.

Since there is no clear understanding of which Fusarium species/strains are currently infecting our solanaceous crops, identifying them is necessary to address this food security issue. This project will use molecular identification procedures to determine the diversity of pathogenic Fusarium in NCR fields. Sequence-based molecular identification of Fusarium is already well established but current sequence databases for local pathovars are missing, which may prevent accurate identification. To address this problem, we have partnered with INTA in Costa Rica, where they have decades of experience cataloging the diversity of Fusarium using similar approaches. INTA has agreed to assist in our development of molecular identification procedures and crop-specificity cataloging in the NCR.

Trichoderma spp. as biological control agents have become one promising option to mitigate the incidence of Fusarium. However, studies have shown that the effectiveness of Trichoderma depends on Fusarium species/strain and even commercial products are not always effective in the field. Thus, this project will validate, in the lab and on-farm, the effectiveness of different Trichoderma species/strains to inhibit or kill local pathogenic Fusarium strains. We will use already developed approaches. In-lab dual confrontation assays will be used to validate the biocontrol agent is effective. Then, we will take products to the original field for corroboration in situ.

The goal is to partner with NCR farmers to test the full potential of Trichoderma-based biocontrol to mitigate Fusarium outbreaks. Our extension specialists have already identified several farmers that are excited to participate, and more farmers will be identified during the course of this project. Once field applications are completed, we will take steps to fully evaluate the effectiveness of the field treatments by molecular detection of previously identified strains and by collecting farmers’ feedback regarding the health and productivity of subsequent crops. Steps will then be taken to disseminate the information to NCR farming communities through extension publications, website updates, webinars, workshops, presentations at farmers’ and professional meetings, and community field-day activities. 

The Objectives / Outcomes for the proposed work are:

1. Determine the diversity of Fusarium in NCR fields by identifying and differentiating local pathogenic Fusarium species, races, or strains affecting various solanaceous crops.
2. Determine the biocontrol effectiveness and crop specificity of available Trichoderma species on locally identified Fusarium species/strains and characterize active compounds linked to the mode of action.
3. Demonstrate/corroborate on-farm biocontrol effectiveness of Trichoderma species/strain to mitigate Fusarium outbreaks in the field.
4. Disseminate new information on the biocontrol of Fusarium in solanaceous crops within the NCR to increase knowledge, adoption, and sustainability.