The effects of heading and benzyladenine applications on branching of apple (cvs. ‘Red Delicious’ and ‘Golden Delicious’) trees in nursery

Abstract

This study was carried out in two independent experiments on one year old apple (Malus domestica cvs. ‘Red Delicious’ and ‘Golden Delicious’) nursery trees with the main purposes of improving lateral shoot formation and increasing the quality of trees. In the first experiment, the effect of different heading treatments (0, 40, 60 and 80 cm above ground) and in the second experiment, benzyladenine (BA) treatments (0, 200, 400, 600 mgL-1) was investigated. Trees were treated with foliar sprays of BA thrice at 7-day intervals in mid-June at the end of the growing season. The tree quality was measured on the basis of their diameter and height of trees, number and length of lateral shoots. A factorial experiment was laid out in a completely randomized block design with 3 replications where each replication was comprised of 10 trees. The results showed that the heading treatments had significant effects on the branching of apple trees. Heading in 60 cm was the best treatment for improving the total number of lateral shoots. The results of second experiment showed that there were significant differences between cultivars and BA treatments. In both experiments, ‘Red Delicious’ had better response to treatments than ‘Golden Delicious’ cultivar. BA treatments had more significant effect on the number and length of lateral shoots than heading treatments. Repeated BA treatments induced lateral shoots more than a single treatment. Key words: ‘Golden Delicious’, height, lateral shoot, ‘Red Delicious’, tree quality.