Objective  Effects of spraying water-soluble, amino acids-containing fertilizer on the phenophase and leaves of the vines, as well as the appearance and fruit quality of Kyoho grapes, were studied.

  Method  Five-year-old Kyoho grapevines cultivated in a rain-free shelter were sprayed 3 times with water-soluble, amino acids-containing fertilizers in 15 d intervals after the beginning of flowering. The vine growth, leaf properties, and fruit quality were monitored for comparison.

  Result  Directly spraying the fertilizers on leaf surface hastened the fruit maturation, promoted the peel coloration, accelerated the maturity and aging of fruit-bearing and vegetative branches, increased the leaf thickness and shoot girth, and significantly raised the soluble solid content in fruit. Among the 4 differently formulated fertilizers, Treatment 4 (containing amino acid ≥ 100 g·L^-1, yellow humic acid ≥ 100 g·L^-1, trace element combination of B, Fe, Zn and Mn ≥ 20 g·L^-1) was found to allow the grapes mature for market 12 d earlier than control. The treatment also significantly increased the leaf thickness, shoot girth, leaf area, and chlorophyll content benefitting photosynthesis. Meanwhile, it enabled 90% of the one-year-old and 76% of the vegetative branches on the vines to reach maturity significantly facilitating nutrient accumulation and flowering for the following year.

  Conclusion  The Kyoho grapes of Treatment 4 had the desirably dark purple color, of appealing eating quality with 18.1% soluble solids and a soluble solid:acid ratio of 54.66, and a high gross revenue of 20 000 yuan per 667 m².