Improving the nutritional value of kiwifruit with the application of agroindustry waste extracts

The purpose of this study was to evaluate the effects of the application of an agro-industrial waste extract (AWE) on the quality of kiwifruit. The AWE was obtained by extraction from apple seeds, rapeseed and rice husks and then boron (0.6 %) and zinc (1.4 %) were added. The effect of AWE as a fertilizer/biostimulant on several parameters of kiwifruit quality (weight, total soluble solids, firmness, dry matter percentage, pH, titratable acidity, antioxidant capacity, ascorbic acid) was then evaluated. The application was carried out on two cultivars of Actinidia deliciosa, cv. Hayward and cv. Green Light, and also in two different cultivation environments. AWE increased the fruit weight in cv. Green Light and in cv. Hayward fruits grown in Piedmont but no increase was observed in dry matter percentage for fruits of both cultivars. The most relevant effect of AWE was the significant increase of the ascorbic acid (AA) content in the fruits of cv. Hayward of all the tested orchards. Fertilization with biostimulants shows a promising future in functional plant nutrition linked to an increase in food quality parameters.