Expert recommends applying light-leaf spot sprays soon

TAG agronomist Jon Bellamy reports waiting until soil temperatures fall to apply light-leaf spot sprays with Kerb (propyzamide), which is only active in the top five centimeters, could turn out to be more costly than beneficial.

“You’ve got to adequately protect against both problems," he said. "If black-grass roots become established, then you can be left with an almost impossible situation. The same applies to LLS which is, in my view, now as great a concern as Phoma. I would suggest it is better to apply propyzamide in combination with a fungicide now and see a possible slight reduction in black-grass control than risk holding off and seeing black-grass become well established combined with poor disease control too."  

Sprays should be applied now because leaf wetness could negatively affect spray opportunities.

“The longer you delay the more likely it is that spray opportunities will decline. My preference for applications from mid-November is to combine Kerb with a robust LLS and Phoma product such as Proline275 (prothioconazole) as they are highly tank-mix compatible," Bellamy said. "But even well-formulated products will not work as designed if applied in compromised conditions."

Organizations in this story

Bayer Crop Science 2 T W Alexander Drive Research Triangle Park, NC 27709

Get notified the next time we write about Bayer Crop Science!