The Effects of Different Level Cluster Tip Reduction and Humic Substance Applications on Yield and Yield Components of Sultani Seedless Grape Variety

This study was performed Sultani Seedless (Vitis vinifera L.) grape cultivar and its vine which was grown on their own roots in a vegetation period of 2015 in Buharkent district in Aydın province. In this research, it was examined the effects on Control (C), 1/3 Cluster Tip Reduction (1/3 CTR), 1/6 Cluster Tip Reduction (1/6 CTR), 1/9 Cluster Tip Reduction (1/9 CTR), 1/3 CTR+TKĠ–Humas (soil), 1/6 CTR+TKĠ–Humas (soil), 1/9 CTR+TKĠ–Humas (soil) applications on grape yield and quality of Sultani Seedless grape cultivar. The results showed that the longest cluster (26.13 cm) with 1/9 CTR, (25.98 cm) with 1/3 CTR, (25.74 cm) with 1/6 CTR and (25.74 cm) with C applications; the largest cluster (14.07 cm) with 1/9 CTR+TKĠ-Humas (soil); the highest berry weight (4.81 g) with 1/3 CTR and (4.63 g) with 1/9 CTR+TKĠ–Humas (soil) applications; the highest berry widh (17.53 mm) with 1/3 CTR application; the highest berry length/berry width (1.40) with 1/9 CTR application; the highest intensity of L* color (44.93) with 1/6 CTR application; the highest intensity of a* color (-7.41) with C application; the highest intensity of b* color (16.08) with 1/6 CTR+TKĠ–Humas (soil), (16.09) with 1/3 CTR+TKĠ–Humas (soil) and (7.41) with C applications. No significant effects were found on grape yield, cluster weight, berry length, pH, oBrix, TA, maturity index and must yield values. To increase the berry weight can be recommended 1/3 CTR application.