Enhancing Pecan Fruit Size and Nutrient Content through Foliar Application of Boron and Zinc

Pecan fruit, also known as pecan nut, is a type of nut that is popular for its rich, buttery flavor and crunchy texture. This research aimed to investigate the effects of spraying boric acid and zinc sulfate on the physical traits of pecan fruit in Erbil, Iraq. The experiment was conducted in the spring of 2022 using a completely randomized block design with three levels of boric acid (0, 1500, and 3000 mg l-1) and three levels of zinc sulfate (0, 2500, and 5000 mg l-1). The spraying was carried out before the flower buds opened, and at the time of harvesting, various physical characteristics of the fruit were measured, including length, width, weight, kernel weight, percentage of hull, percentage of shell, percentage of kernel, and absorption of elements in leaves and nuts. The results showed that spraying with boric acid (3000 mg  l-1) and zinc sulfate (5000 mg  l-1) had the greatest effect on increasing fruit length, while the fruit width was highest in the zinc treatment (5000 mg  l-1), and it was significant compared to the control treatment. None of the treatments had a significant effect on fruit weight, kernel weight, percentage of shell, and percentage of hull skin. Moreover, the spraying significantly increased the amount of boron and zinc elements in leaves and nuts. Therefore, it can be concluded that spraying with boric acid and zinc sulfate can be an effective method to improve the physical characteristics of pecan nuts and increase the absorption of essential elements in leaves and nuts.