The effects of benzyladenine and naphthalene acetic acid applications on fruit thinning and quality in some apple cultivars grown in Igdır ecologic conditions

This study was conducted in order to determine the effect of Naphthalene Acetic Acid (NAA) and Benzyladenine (BA) at different doses on fruit thinning and some fruit quality traits (fruit width, fruit length, fruit weight, fruit flesh firmness, stalk length, stalk thickness, yield efficiency, TSS, titrable acidity, pH) in Granny Smith, Golden Delicious, and Red Chief apple cultivars grafted on MM 106 clone rootstock grown under the Igdır ecological conditions In the study, doses of 5 and 10 ppm of Naphthalene Acetic Acid (NAA) and 100 and 150 ppm of Benzyladenine (BA) were applied to apple varieties with 5-6 aged in the the same maintenance conditions 20 days after from full flowering. Application of thinning was also pruned on the trees leaving a fruit on each branch in small fruit period following June-drops, by the hand. Fruit thinning ratio was determined by pre-application and pre-harvest counting. The highest thinning ratio was found in the Granny Smith variety, with 5 ppm (93.80%) and 10 ppm (91.65%) of NAA, 100 ppm (89.88%) and 150 ppm 88.98%) in the trial. According to the results of the experiment, applications of 10 ppm of NAA and 100 and 150 ppm of BA were found to be important for fruit juice and fruit quality. Furthermore, by the hand pruning applications yielded the better results compared with chemistry in respect of increasing fruit weight. In general, the effects of applications were statistically significant on fruit quality parameters. Exclusively, the varietal x application interactions were found to be significantly effective on fruit weight, stem thickness, fruit meat hardness and titratable acidity.