Exploring Biochar Potential to Enhance Biocontrol of Soil-Borne and Foliar Pathogens in Vegetable Crops.

Indiana vegetable growers can benefit from the rapidly expanding market for food grown locally using environmentally friendly farming practices, but there is an increasing need for research to address disease problems. Tomato and carrot are important vegetable crops with significant opportunity for growth in Indiana. However, vegetable growers cite disease by Phytophthora capsici, root-knot nematodes (Meloidogyne spp.), and Alternaria leaf blights as significant barriers to high quality production of these crops. Few sustainable alternatives are available to control these pests in organic systems, and fungicides are becoming less effective for control of P. capsici in conventional systems because of increases in fungicide resistant populations. Biocontrol practices that modify the soil microbial community to enhance beneficial microbial species with antagonistic ability or induce systemic resistance have potential to help growers address these pathogen challenges. Incorporation of cover crops into a crop rotation and application of biochar soil amendments have resulted in enhanced populations of microbial species known to suppress pathogens and induce systemic resistance. The objective of this project is to evaluate the capacity for biochar soil amendments alone and in combination with cover crops to improve tomato and carrot plant performance and reduce disease incidence by these important pathogens. Results will contribute to a better understanding of how biochar amendments interact with soil biota to influence crop growth and disease susceptibility. Management strategies developed will provide vegetable growers with additional effective and sustainable production options to manage pests and increase crop yields.