Project Overview

Reports

Commodities

• Vegetables: tomatoes

Target Pests

• Target Pests: fungus, weeds

Practices

• Pest Management: chemical control, cultural control, monitoring/scouting, mulches - general, mulching - plastic, prevention, soil solarization, weed ecology

• Crop Production: fertilizers, greenhouses, nutrient management, varieties and cultivars

• Natural Resources/Environment: indicators, soil stabilization

• Production Systems: organic agriculture, permaculture

• Soil Management: organic matter, soil microbiology, soil quality/health

The Problem or Opportunity
Weed pressure and soilborne diseases such as southern blight (Sclerotium rolfsii) remain persistent challenges for tomato growers in the Southern United States. Although labeled herbicides such as metribuzin, S-metolachlor, and halosulfuron are available, their performance can be inconsistent in high-residue or organic-amended systems. Meanwhile, many small and mid-scale tomato producers have begun using biochar to improve soil health, but there is limited information on how these products interact with herbicides or influence disease incidence. Growers have also reported using heavy-duty tarps to cover tomato beds through the winter to suppress weeds before transplanting, but its effects on soil biology and disease pressure remain largely unknown.

The Approach
This project will evaluate the combined use of overwinter tarping, biochar blends, and labeled herbicides as an integrated weed and disease management strategy in tomato production. Field trials will be conducted at the Mississippi State University Truck Crops Research and Extension Center in Crystal Springs, MS. Treatments will include five commercially available biochars used by regional growers, Seven Springs Farm “Neversink Blend” (hardwood-based), Black Owl Biochar (woody biomass), Cool Terra® (wood-derived), Wakefield Poultry Litter Biochar, and Rice Husk Biochar (Mississippi-sourced), with and without overwinter tarping, and in combination with standard herbicide programs.

Anticipated Impact
Measurements will include weed density and biomass, tomato growth and yield, soil microbial diversity (using a Biolog EcoPlate™ assay), and southern blight incidence and severity. Results will provide regionally relevant data on how common biochar products and tarping practices affect both weed management and soilborne disease in tomatoes. The expected outcome is a practical IPM framework that integrates cultural, chemical, and soil-amendment strategies, directly addressing grower-identified needs for sustainable tomato production in the Southern region.