Bacterial Wilt

Disease

Xanthomonas translucens pv. poae


Bacterial wilt is characterized by tiny red-copper-colored spots first appearing about the size of a dime. As more plants die, spots become larger. Small, yellow leaf spots, streaked tan to dark brown spots, dark green, water soaked lesions, shriveled blue to dark green leaves, and yellow elongated leaves are all symptoms that have been associated with bacterial wilt. Numerous small, pit-like or speckled spots, about 0.25-0.75 in. (0.5-2 cm) in diameter, may develop on greens.

Bacterial wilt was a major problem on one cultivar (Toronto) creeping bentgrass, but continues to be an issue on annual bluegrass in many regions of North America. Outbreaks tend to occur during extended periods of rainfall. The disease can be devastating if prolonged rainfall is followed by bright sunny days and warm weather. The disease is most devastating where sand top dressing programs are implemented.

  • Crops Affected: Turfgrass

    Damage

    The location of this disease is golf courses. General symptoms are a circle, spotting, wilted, or irregular coloring. Foliar symptoms are spotting, browning, and yellowing. This can occur during the months of June, July, August, September, and October. Hosts of the disease are Kentucky Bluegrass, Perennial Ryegrass, Creeping Bentgrass, and Annual Bluegrass.

    Management

    Culturally, there is little that can be done to manage this disease. Mowing can be implemented in the afternoon, once the turf has dried to discourage the spread of the bacterium on wet turfgrass. Mowers should be dedicated for use only on affected greens and should be disinfested with bleach after use. Mowing height should be increased and mowing frequency decreased. Abrasive cultural practices, such as vertical cutting, topdressing and aeration, should be avoided when the disease is active. Greens chronically affected by bacterial wilt should be reestablished with resistant cultivars.

    All of the seeded cultivars of creeping bentgrass have so far been resistant to bacterial wilt caused by X. translucens.