Effect of foliar application of urea, zinc sulphate, and 2,4-D on kinnow mandarin: A review

Foliar nutrition is practiced by the fruit grower's worldwide. Nitrogen is a principle fertilizer nutrient routinely applied every year to both young and mature fruit trees. There is a positive relationship between N rate and Kinnow shoot growth. Application of N increased shoot growth, plant height, spread, and canopy volume in Kinnow. The growth, yield and quality of acid lime fruits were significantly influenced by the application of zinc and iron fertilizers (0.25, 0.50 and 0.75%). Maximum growth and good quality fruit and yield were observed with two sprays at one-month (Feb-march) intervals of 0.5% ZnSO₄ and 0.5% FeSO₄. The 2,4-D chemical could thus be used to increase fruit yield under conditions that favour fruit drop such as extreme temperatures as well as water deficits such as those that are prevalent in Botswana. The application of 2,4-D is more effective at the earlier stages of fruit development since navel oranges were shown to be more susceptible to fruit drop when small in size.