The Effect of Biochar on the Biological Properties of Soil, Growth Vigour, and Quality of Strawberries After Replantation

Apple replant disease (ARD) is a significant problem in regions with intensive fruit production. ARD deteriorates the production properties of soil, reduces yield, and results in lower fruit quality. The effects of ARD can be mitigated with organic amendments applied to soil to improve its productivity. Our experiment was conducted on a farm in western Poland. Biochar was added to replanted soil at 5%, 10%, and 20% by volume and its effect on the physicochemical and biological properties of the soil, the growth vigour, and the quality of strawberries was analysed. Strawberry plants were planted in soil which either had been used for nursery production (replanted soil) or had never been used for this purpose (agricultural soil). The results of our study confirmed earlier reports on the negative consequences of ARD. The replanted soil was more saline and contained less organic matter than the agricultural soil. The plants growing on the replanted soil developed worse. When biochar was added to the replanted soil, depending on its percentage content, the organic matter content and soil respiration rate almost doubled, whereas the count of bacterial taxonomic units increased. As a result of these changes, the root mass of the plants growing in the replanted soil increased by nearly 50%, whereas the root collar mass of shrubs and their leaf area increased by 25 to 30%. The average fruit weight also increased by about 40%. The optimal biochar content in the replanted soil was 10%. The biochar content of 20% did not cause significant changes in most of the parameters under analysis.