Influence of an Alternative Soil Management System to Herbicide Use on Tree Vigor, Yield, and Quality of Apple Fruit

The aim of this study was to investigate the effect of alternative soil maintenance systems in a ‘Gold Chief’ apple orchard to the herbicide strip on tree growth, yield, and optimal fruit quality during 2012–2016. We compared several floor management systems: organic mulch comprised of Miscanthus spp., mechanical cultivation, black polypropylene cover, and herbicide strip as the control, with particular emphasis on the suitability and effectiveness of the organic mulch. During this five-year experiment Miscanthus spp. mulched trees grew most vigorously and significantly more than trees from other systems. The increment of the trunk cross-sectional area was higher for Miscanthus spp. mulched trees when compared to both mechanical fallow and herbicide strip. On average, fruits from trees grown in Miscanthus spp. plots were significantly larger than fruits from mechanical fallow and black polypropylene cover plots. The cumulative yield from the entire experiment was not significantly different for organic mulch, herbicide strip, and black polypropylene cover and was significantly higher than the mechanical cultivation. Different floor management systems had a significant effect on the solid soluble content in fruit both directly after harvesting and after storage. Our study shows that organic mulch can be a good alternative for soil management in orchard production systems.