Evaluation of Phoma macrostoma for management of broadleaved weeds in wheat and barley

Project Code BPR11-010

Project Lead

Eric Johnson - Agriculture and Agri-Food Canada

Objectives

To develop efficacy and crop tolerance data in support of a regulatory submission of Phoma macrostoma for the control of three weeds in spring wheat and barley: wild mustard (Sinapis arvensis), dandelion (Taraxacum sp.), and cleavers (Gallium aparine)

The broadleaved weeds wild mustard, dandelion, and cleavers are a major issue in wheat and barley production and greatly affect growth and yield in western Canada. Currently, growers rely on pre- and post- emergence broadcast applications of broad spectrum herbicides to control these weeds. Frequent application of high levels of herbicides increases risk for weed resistance development and agricultural environmental contamination. During the Annual Biopesticides Priority Setting Workshop in 2010, broadleaved weeds in wheat and barley were selected as a priority issue by growers. P. macrostoma, a novel bioherbicide discovered and developed by AAFC scientist Karen Bailey, and now being commercialized by Scotts Canada, was identified as the preferred solution.

P. macrostoma is a fungus that causes photobleaching and root inhibition in susceptible weeds when broadcasted to soil as a granule. AAFC has been working with the Scotts Company, SK for several years toward registration of P. macrostoma as a bioherbicide for broadleaved weed control in turfgrass and other non-food use plants in Canada and the United States. Studies of host range have shown that the bioherbicide likely has no phytotoxic effect on wheat and barley plants. The current project is to test field efficacy of P. macrostoma for control of the three weeds, identify the application rates and assess the wheat and barley crop tolerance to this bioherbicide.

This is a one-year efficacy trial. The trial will be conducted in Scott Research Farm of AAFC, Scott, SK. Efficacy and crop tolerance will be evaluated based on weed count, weed phytobleaching rating, and grain yield.