Effects of apple fruit fermentation (AFF) solution on growth and fruit quality of apple trees

It has been demonstrated that the use of organic materials in fruit orchards can effectively increase soil fertility, fruit production and fruit quality. Insect and disease damage, crop thinning, natural drop cause abscission and abscised parts are a source of organic additives for orchard production. In this study, we developed a fermented nutrient solution composed of young apple fruits, brown sugar, a fermenting agent and water. Diluted solutions (1:100 and 1:200) of this nutrient solution were sprayed on 2-year-old and 12-year-old apple (Malus domestica (Borkh.) ‘Fuji’) trees. The results showed that foliar spraying of the fermentation solutions significantly improved tree height, trunk circumference, shoot growth and leaf area of young apple trees, and increased the fruit weight, shape index, firmness, soluble solid content, volatile compound content and vitamin C content of adult apple trees, as compared to the control treatment. The effects of the 1:200 diluted nutrient solution were significantly greater than those of the 1:100 diluted nutrient solution. Foliar spray of a nutrient solution derived from young apple fruit promoted vegetative growth and fruit quality.