Investigating the role of potassium and urea to control fruit drop and to improve fruit quality of Dhakki date palm

Fruit drop is a key issue with date palm cultivars that can be addressed with a variety of methods and strategies. Foliar application of macronutrients can be more effective in inhibiting fruit drop and improving the quality of date fruits. The current study was carried out to investigate the possible role of potassium (K) and urea to reduce fruit drop and improve the fruit quality of Dhakki date palm. It was conducted in a complete randomised block design with seven treatments and three replications at Pakistan's Agricultural Research Institute, Dera Ismail Khan. The treatments used were: (i) Control (distilled water spray); (ii) Potassium sulphate (K2SO4) at 1 %; (iii) K2SO4 at 1 % + Urea at 2 %; (iv) K2SO4 at 2 %; (v) K2SO4 at 2 % + Urea at 2 %; (vi) K2SO4 at 3 % and; (vii) K2SO4 at 3 % + Urea at 2 %. All the concentrations were sprayed at Kimri stage of fruit development during two consecutive growing seasons. Twenty-one date palms of equal size and age were chosen for the assessments to measure percent fruit drop and other physicochemical variables, including fruit length, fruit diameter, fruit weight, pulp percentage, yield/bundle, pH, total soluble solids (TSS), K content in fruit, and all sugars (percent) of harvested date fruit. The results revealed that bunch spray of K significantly affected all the parameters during both seasons. Application of K2SO4 alone and in combination with urea not only effectively reduced the fruit drop but also improved fruit quality in date where, K2SO4 applied at 2 % combined with urea was the best concentration in reducing fruit drop, enhancing other physicochemical attributes, and improving fruit quality of Dhakki date palm. This study may effectively contribute to reduce the fruit drop and enhance the fruit quality by using K and urea, enabling farmers to improve the date yield and increase economic growth. (c) 2022 The Author(s). Published by Elsevier B.V. on behalf of King Saud University.

Automated summary

This study investigated the role of potassium (K) and urea in reducing fruit drop and improving fruit quality in Dhakki date palm. The results showed that the application of K2SO4 combined with urea at a concentration of 2% was the most effective in reducing fruit drop and improving physicochemical attributes of the date fruits.