301 Bioregulators Affect Apple Yield and Quality Attributes

Abstract

Experiments were conducted in 1995 and 1996 to investigate the effect of Accel and Carbaryl sprayed 2 weeks postbloom on apple fruit yield and quality and to relate the degree of fruit set reduction to the yield of three apple cultivars (Empire, Jon-A-Red, and Braeburn). The treatments consisted of Accel 25 ppm, Accel 50 ppm, Accel 75 ppm, Carbaryl 0.05%, Carbaryl 0.1%, Carbaryl 0.2%, and an unsprayed control. Trials conducted over the 2 years indicated that Accel and Carbaryl reduced the fruit set of three apple cultivars as shown by the lower number of fruit per limb cross-sectional area on the sprayed trees compared to the unsprayed trees. Most effective concentrations in reducing the fruit set on apples were Accel 50 ppm, Accel 75 ppm, Carbary 0.01%, and Carbaryl 0.2%, with high yields and high fruit rates. Therefore, it was concluded that these are the best concentrations for thinning of apples. Other quality attributes, such as pH, sugar content, and percent fruit red were also increased by the treatments. The treatments did not influence the number of seeds in the fruit, fruit length, fruit diameter, and fruit length: diameter ratio.