http://forest.geoman.ru/forest/item/f00/s00/e0000591/index.s... По аналогии с русским источником. т.е болезнь берет начало сверху, а не снизу как при balckleg'e.
Aerial Stem Rot is caused by the same organism attacking the plant from the top down, through wounds or natural openings in the leaves. After infecting the leaves it travels down the stem to the developing tubers. Like most bacterial infections this is usually transported in water, so keep the foliage dry by using drip irrigation. If you must use sprinklers then it’s best to water in the morning or early evening, so leaves have a chance to dry out before nightfall.

The most important way to control this disease is by planting certified disease-free seed potatoes. If this disease has been a problem in the past, it is better to use small, whole tubers rather than cutting big ones into small pieces (which damages them before they even go in the ground). You can also plant them at a shallow depth to encourage quick emergence (hill them up later to increase soil depth). You should always rotate potato crops annually and try to remove all tubers from the soil, as any that remain in the ground can harbor the disease (the bacteria can’t survive outside of living plants for very long). Also give the plants plenty of room (for good air circulation) and make sure the soil is well-drained.

To minimize rot in storage it is important to ensure that all tubers are undamaged. If you are storing them in a root cellar, you should put them in crates or boxes where they can be conveniently inspected occasionally.