The Effect of Foliar Application of Naphthalene Acetic Acid on Growth, Yield and Fruit Quality of Sweet Pepper cv. California Wonder

In order to study the effects of foliar application of naphthalene acetic acid (NAA) on growth, yield and fruit quality of sweet pepper "California Wonder", an experiment was conducted in a randomized complete block design with three replications in the Research field of Faculty of Agriculture (University of Zanjan, Iran) in 2016. Treatments were consisted of NAA at five levels of 0 (control), 50, 100, 150 and 200 mg.L-1. The results showed that foliar application of NAA had significant effects on vegetative traits, yield and its components, and fruit quality. The highest fruit number per plant (5.6 and 6) and yield (24.6 and 24.9 t.ha-1) was achieved at 50 and 100 mg.L-1 NAA. The maximum plant height and chlorophyll index were obtained by application of 100 and 150 mg.L-1 NAA. The highest amount of total soluble solid (4.93 °B), vitamin C (103.73 mg.100ml-1) and fruit firmness was recorded at 100 mg.L-1 NAA. According to the results, application of 100 mg.L-1 NAA can be proposed to improve yield and fruit quality of sweet pepper.