Also known as brown rot of potatoes, potato bacterial wilt is an extremely destructive plant pathogen that affects potatoes and other crops in the nightshade (Solanaceae) family. Potato bacterial wilt is prominent in warm, rainy climates around the world, causing millions of dollars in economic loss.
Unfortunately, there is very little you can do about brown rot of potatoes in your garden, and currently, no biological or chemical products have proven effective. With vigilance, however, you may be able to manage the disease. Read on to learn the best ways to control brown rot of potatoes.
Bacterial Wilt Symptoms on Potatoes
The first step in its management is knowing what the disease looks like. Initially, visible symptoms of potato bacterial wilt generally consist of stunted growth and wilting during the hottest part of the day. In the early stages, the disease may affect only one or two young leaves at the tips of stems, which rebound in the cool of evening. From this point, the disease progresses rapidly as the entire plant wilts, yellows and eventually dies.
The disease is also easy to spot by brown streaks in the vascular tissue of the stems. When infected stems are cut, they exude beads of sticky, slimy, bacterial ooze. In later stages of the disease, sliced potatoes also display a grayish-brown discoloration.
Although potato bacterial wilt is usually transmitted by infected plants, the pathogen also spreads via contaminated soil, on tools and equipment, on clothing or shoes, and in irrigation water. It can also survive on seed potatoes.
Controlling Potato Bacterial Wilt
Plant only disease-resistant potatoes. This is no guarantee of protection, but chance of infection is much higher on home-saved seed potatoes.
Discard diseased plants immediately. Dispose of infected plants by burning or in tightly sealed bags or containers.
Clean and disinfect tools after working in infected soil. Remember to carefully water plants to avoid spreading disease in run-off.