August 27, 2003

Welcome to the NDSU Bravo/Quadris Blightline for August 27th sponsored by Syngenta and the Quadris/Bravo Performance Pak.

A new report of late blight have been confirm from a field in Walsh County. Although condition for spread and development of late blight has not been favorable in most of the region the high humidity and resulting dew on the foliage can aid in the in-field spread and development of the diseases. The forecast for the coming week is for cooler temperatures and scattered thunderstorms, which would provide conditions favorable for late blight and increase the chances of field-to-field spread. If these conditions occur, growers should scout fields for late blight and maintain an active fungicide program. Growers in northeastern North Dakota should continue protectant fungicide applications for the remainder of the season on a weekly schedule until the vines are dead, dead, dead. If disease pressure increases because late blight is present, or the weather becomes cool and wet, consider a five-day interval between spray applications. Late season infection by late blight can result in tuber infection and tuber decay in storage, so growers should consider fungicides that provide tuber blight protection such as Gavel or Omega, or applications of chlorothalonil plus tin to reduce late season inoculum. These fungicides should be applied as the final two or three sprays of the season for best tuber protection. Good vine kill of fields destined for storage will reduce the chance of late blight tuber infection, and subsequent problems in storage.

Thank you for using the Bravo/Quadris Blightline.

---

TO HOME