VEGETATIVE AND PRODUCTIVE RESPONSE OF YOUNG 'WILLIAMS' PEAR TREES TO REGULATED DEFICIT IRRIGATION (RDI), MULCHING AND THEIR COMBINATIONS

This field experiment was designed to assess the vegetative and productive response of young ‘Williams’ pear trees to regulated deficit irrigation (RDI), mulching and their combinations with the aim of optimising such parameters. Using a water budged methodology, four levels of irrigation, specifically 100% of ET (control) and deficits of 80, 60 and 40%, were applied to 10 trees, 5 of which were mulched by a 10 cm layer. The experiment was conducted in Kosovo (Dukagjini Plain) during 2013 on a pear orchard of 10 ha in third year using a nested experimental design. Using ANOVA two-way with post hoc testing we found significant changes in a series of vegetative and productive parameters. Irrigation levels significantly influenced leaf surface and area, shoot length, total number of fruit and their weight and consequently total yield. In addition, mulching had a positive effect on all parameter values, in particular on shoot length and fruit diameter during all their growth but more remarkably in the third stage. RDI and mulching had a combined effect on shoot length and canopy volume while changes were not significant for number of leaves, number of shoots, number of fruits of extra class and first class. Considering the young age of trees and long-term consequences of water stress the experiment will be continued.