Effect of training system and pruning severity on the yield and fruit quality characteristics of kiwifruit

Continual bearing and production of the highest quality fruits in kiwi requires initial training and regular annual pruning. Effects of three training systems including T-bar, as a common training system, Modified TY (MTY) and Y-shape (Y), and two pruning levels (60 and 80 buds per vine) was studied on yield and quality characteristics of kiwifruit ‘Hayward’. Experiment was carried out in a factorial experiment using randomized complete block design (RCBD) with three replications in 2012. Results showed that the highest yield was obtained in Y80 treatment and the highest content of fruit tissue firmness, TSS and TSS/TA ratio were observed in Y60 treatment. The lowest fruit dry matter percentage belonged to MTY60, but fruits vitamin C was observed in Y60, Y80 and MTY60 systems. The highest content of total phenol was obtained in Y60 and MTY60 systems. However, the highest content of fruits extract total chlorophyll and antioxidant capacity at harvest time was observed in Y60. According to the results of this study, Y training system and pruning level of 60 buds per vine increased yield and quality of kiwifruit, respectively.