Premature Ripening? Might Mean Late-Season Disease

It is important to scout fields and examine plants to know what is causing symptoms such as premature ripening. Don’t let the colour change of a small percentage of diseased plants affect the harvest timing of the whole field!

Across the prairies, there are several reports of late-season diseases, especially sclerotinia and blackleg. In some fields, there is a significant amount of sclerotinia (up to 30% infection). In Manitoba, some of these fields were protected with a fungicide (at 20 to 30% bloom) and it appears the infection occurred later near the end of flowering. There is still reasonable seed set in some fields on these plants so they need to be considered when staging for swathing, but in most cases they represent much less than half of the total yield. Swathing the healthy plants prematurely in an attempt to salvage these diseased plants may lead to decreased yield and green seed issues. Evaluate the entire field for yield potential and determine what portion of yield these plants represent when gauging swathing timing. The best strategy may often be to focus on swathing when the healthy crop is at the proper stage, utilizing the overnight or morning dew to minimize shattering of the diseased plants as much as possible.