The effect of foliar application of boron and zinc on qualitative traits of hazelnut cultivars

Abstract

The foliar application of nutrients is prevailing in most orchards and it has noticeable favorable effects on vegetative traits, yield and fruit quality. The effect of foliar application of zinc (Zn) and boron (B) on qualitative traits of hazelnut fruits was explored in a factorial experiment based on a randomized complete block design with 12 treatments and three replications in Shavak Village of Rudsar County, Iran. The experimental factors included cultivar (including a local variety, ‘Fertile’, and ‘Ronde du Pimount’) and foliar application (control, B at the rate of 3 mg/L, Zn at the rate of 3 mg/L, and a mixture of B and Zn at the same rates of 3 mg/L) in spring. The recorded traits were antioxidant, anthocyanin, catalase, peroxidase, phenolic compounds, fat, ash, protein, Zn, B, and P. The results indicated that the effect of cultivar was significant (p < 0.01) on anthocyanin, catalase, peroxidase, phenolics, fat, ash, Zn, and B. Mean comparison for the effect of the foliar application revealed that the highest anthocyanin was observed in the local variety. In addition, the effect of foliar application was significant (p < 0.01) on anthocyanin, catalase, peroxidase, fat, ash, protein, Zn, B, and P. Means comparison for the effect of cultivar revealed that cv. ‘Ronde du Pimount’ had the highest anthocyanin, catalase, peroxidase, fat, and Zn content in its kernels. The effect of the foliar application of the micronutrients was positive on the measured qualitative traits. The foliar application of B had a more significant impact on the traits.