Biofumigation as an IPM Strategy

View the project final report

• 2006 annual report
• 2007 annual report
• 2008 annual report
• 2009 annual report

Commodities

• Agronomic: potatoes

Practices

• Education and Training: demonstration, extension, on-farm/ranch research
• Farm Business Management: budgets/cost and returns
• Pest Management: mulching - plastic, soil solarization
• Production Systems: organic agriculture
• Soil Management: general soil management

Managed decomposition of crop residue, biofumigation, is a biointensive strategy that has the potential to reduce the use of toxic biocides used to kill soilborne pathogens. Research conducted in Wisconsin and elsewhere has shown this technology can reduce nematodes, fungi, and weeds. Cover crops used for biofumigation have the potential to harbor beneficial insects as they grow and the return of plant residues to soil impacts nutrient turnover and soil parameters. We propose to work with a group of motivated, innovative growers participating in the “Healthy Grown” potato ecolabel program to adapt biofumigation for Wisconsin vegetable/potato cropping systems. This technology can be adapted to any cropping system and holds promise for a wide range of soil-borne diseases. Outcomes include building a knowledge base and expertise among farmers about biofumigation and educating farmers and the public about the crucial ecosystem services provided by soil organisms and the value of healthy soils as a natural resource. Increasing biofumigation will affect the profitability and sustainability of potato production in the NC region, reduce toxic pesticide inputs to the environment, and ease concerns from the public about exposure to broad-spectrum volatile compounds, thereby sustaining agriculture in highly populated areas. We will conduct two experiments managed by researchers and collaborate with farmers to devise their own trials. The success of our activities will be evaluated on the basis of farmer participation, surveys, and audience response at meetings collected using response pads and associated software. Outputs include written media and recommendations aimed at a broad agricultural clientele.

Biofumigation, the managed release of degradation products from plant residues that are toxic to soil organisms, is an effective practice for pest and pathogen control. The principle components of biofumigation are appropriate plant material, tools to chop and incorporate the material into soil, and manipulation of the soil environment to affect the timed release of decomposition products. For all of the human effort involved, the success of biofumigation also rests with the soil microbial community. It is the activity of the rich parade of litter- and soil-dwelling microbes that release volatiles, break down organic matter, and change the fabric of the soil community to the credit of the microbial consortium responsible for litter breakdown, nutrient cycling, disease and pest suppression, and filtering ground water. These ecosystem services are an integral part of agriculture and are supplanted, in part, by anthropogenic inputs such as fertilizer, pesticides, and tillage.

Important short-term outcomes of this project are:

• Building a knowledge base among growers and agribusiness representatives about ecosystem services available in the soil and the organisms involved
• Increasing the expertise of farmers about cover crop management and the practice of biofumigation
• Increasing awareness of farmers, crop consultants, county agents and industry representatives of the value of biofumigation relative to soil fumigation with synthetic chemicals.

We have a research record, supported by an extensive public and scientific literature, that shows biofumigation is effective. Our initial focus group, farmers growing potatoes under the innovative ‘Healthy Grown’ progam, is highly motivated and has demonstrated willingness to alter crop management practices, adopt new strategies, and proactively forge new paradigms for agriculture. Because this group produces an identifiable product with an established marketing campaign, their media attracts the attention of consumers and environmental advocacy groups.

By the end of this project, we expect to attain our intermediate-term outcomes of:

• Increasing the use of cover crops in vegetable production systems in Wisconsin
• Increasing the number of growers who consider ecological principles when making management decisions.
• Increasing public awareness of biologically-based pest management alternatives and efforts by farmers to promote land stewardship