Enhancing tuber quality, storage performance and yield response of potato to combined foliar application of zinc sulphate and boric acid

Potato (Solanum tuberosum L.) is a popular food source worldwide, cultivated for tuber consumption, and plays an important role in food security in developing countries. Potato plants (Montreal cultivar) was exposed to Zinc Sulphate (0, 500, and 1000 mg/L) and Boric Acid (0, 50, and 100 mg/L) in a two factorials experiment based on a randomized complete block design (RCBD) with three replications. The experiment was conducted in the Vegetable Field at the University of Mosul during the 2024 spring growing season. Application of Zinc Sulphate (1000 mg L− 1) and Boric Acid (100 mg L− 1), separately or in combined, increased the plant height, the number of aerial stems, the leaf area, the yield per plant and per hectare. During postharvest storage, the amounts of dry matter (16.14%), starch percentage (18.00%), tuber Boron (38.91%), tuber zinc (17.55%), and tuber firmness (10.19%) were decreased, while the TSS value was increased by 24.17%. Foliar application of combined treatments from Zinc Sulphate and Boric Acid (500 or 1000 mg/L Zinc Sulphate with 50 or 100 mg/L Boric Acid) significantly slow these trends during post-harvest phase. However, the combination of 1000 mg L− 1 Zinc Sulphate and 100 mg L− 1 Boric Acid yielded the greatest values on all of the traits examined associated with tuber quality. This treatment maintained the greatest tuber firmness (18.12 lb in²), dry matter content (19.00%), specific gravity (1.07 g cm-²), starch percentage (12.94%), Zn (24.36 mg/L) and B (22.50 mg/L) contents, and the least amount of weight lost (5.23%) and total accumulation of soluble solids (5.15%) during the period of cold storage. Thus, we recommend the application of 1000 mg/L Zinc Sulphate + 100 g/L Boric Acid to improve yield and quality of potato tubers.