Results of pot experiments on control of apple replant disease

Soil for the experiments was taken from the orchards in which replant disease has been previously determined. It was treated in different ways. Besides steaming and formalin (standard treatments) two fungicides (Aliette and Captan), monoammonium phosphate, magnesium limestone and several organic materials (peat, decomposed bark and biohumus) were applied. Apple seedlings of cv. Antonovka were used as test plants. Each experiment lasted for about three months. All treatments positively influenced the growth of the test plants. The most effective appeared to be biohumus in dosage of 10-20% and monoammonium phosphate in dosage of 2g/liter of soil. Slightly less effective were peat and decomposed bark. The effectiveness of both fungicides differed according to the experiment. NPK, applied only once, was practically non-effective and magnesium limestone was also non-effective.