The Use of Organic Additives for Replanted Soil in Apple Tree Production in a Fruit Tree Nursery

How soil is used affects its production characteristics in the future. Under ARD (Apple Replant Disease) conditions, replanted soil’s physical, chemical and biological properties deteriorate. Their improvement is possible through, for example, increasing the content of organic matter in the soil. The study aimed to assess the effect of two organic additives for replanted soil on its physical, chemical and biological properties, as well as on the vegetative growth of apple trees of the ‘Gala Schniga SchniCo(s)’ cultivar grafted on M.9 rootstock. The experiment was performed in 2021, in western Poland, on a nursery farm. The trees were planted in pots filled with soil from two stations: soil previously used for the production of apple trees (replanted soil) and nursery material (agricultural soil) unused for production so far. To fertilise it, three different portions of biocarbon and Carbomat Eco soil conditioner were added to the replanted soil. The experiment showed that apple trees grown on replanted soil had fewer side shoots, a smaller leaf area and a lower mass of leaves than those grown on agricultural soil. Furthermore, supplementation of replanted soil with organic additives caused a significant increase in its enzymatic activity and respiration, increased the rate of photosynthesis and improved several parameters determining the strength of vegetative growth in apple trees.