Marketing of composts prepared from yard wastes increasingly being diverted from landfills will become a problem. During maturation, composts are naturally recolonized by beneficial microorganisms that provide biological control of some soilborne plant diseases. Controlled addition of specific biocontrol agents to composts, followed by formulation of potting mixes with this product induces predictable suppression to the most important soilborne plant pathogens. This approach to disease control promises to significantly reduce pesticide use, improves compost quality and en lances opportunities for recycling of solid wastes through composting. The objectives of this phase I proposal are 1) to scale-up the technology for the controlled addition of biocontrol agents to composts and 2) to develop a potting mix suppressive to diseases caused by soilborne plant pathogens. The potential for the commercial application of this process, based on the wide-scale adoption by horticultural industries of natural compost with limited and variable suppressiveness spectra are numerous.Applications:The primary objective of this project is to scale-up production of biocontrol agent-fortified compost-amended potting mix predictably suppressive to soilborne plant pathogens. Specific subobjectives are: 1) optimize procedures for inoculation of compost with biocontrol agents, 2) formulate a potting mix with the fortified composts that optimizes efficacy of the biocontrol agents, 3) verify efficacy of the product by performing disease suppression and plant growth bioassays, 4) determine the keeping quality of the product. The commercialization potential is extensive. The greenhouse industry alone is a multibillion dollar industry. Many millions of dollars a year are lost due to plant diseases that can be controlled by this approach to biological control.
