Use multiple tools to fight vine crop diseases, eVGN June 2013

Vine crops are susceptible to many diseases, and no single strategy is adequate to manage all of them, according to Kathryne Everts, a professor and plant pathologist at the University of Maryland.

Growers must deploy many tactics from their “toolbox” to combat losses, Everts said. These tactics include cultural practices like the use of resistant or partially resistant cultivars, cover crops that are incorporated as green manures or used no-till and fungicides. All of these tactics are beneficial under some field conditions and in the presence of certain pathogens, according to Everts.

Different control practices vary in their effect on different diseases. For example, no-till cover crops are more effective on reducing fruit rot of pumpkin, but of little use on powdery mildew. Cultivar resistance of some cultivars will reduce powdery mildew pressure but is of little use on fruit rot. Overreliance on only one control tactic or tool will leave the crop vulnerable to catastrophic loss if that one tool fails. Incorporation of multiple tools into a disease management program will reduce risk of losses, according to Everts.

The recommended “best management practice” is to combine practices. Used together, they form a robust base to a disease management program. For example, use of cover crops has increased in the past 10 years, and there are questions about how much a cover crop contributes to an overall disease management program, according to Everts.

– Matt Milkovich