Growth and fruit production of asian pear trees grown on Y-, T-, and vase-training systems

This study was carried out to evaluate the effects of training systems on growth and fruit production of ‘Niitaka’ pear ( Pyrus pyrifolia L.) trees in the first 8 years in South Korea. The training systems included Y-trellis (YT), T-trellis (TT), and vase-pergola with either two (VP I) or three main branches (VP II). Tree spacing for YT, TT, VP I, and VP II were 6.5 m between tree rows, and 3.0, 6.0, 3.0, and 6.5 m between trees, respectively. The TT trees had lower tree height, canopy area, and number of new shoots, average length of new shoots, and trunk cross sectional area as compared to those in other training systems in year 3 or year 8. The TT and VP II systems were slow to fill the allotted space from year 3 to 8. The VP I trees had comparatively rapid development of the tree canopy, high cumulative yield efficiency per tree, high cumulative fruit yield per area, and large fruit size, as well as low operation hours for orchard management. Fruit quality parameters, such as fruit shape, soluble solids content, firmness, and titratable acidity, were not consistently affected by training system in years 5 and 8.