THE INTERACTIVE EFFECT BETWEEN POTASSIUM AND BORON ON GROWTH AND PRODUCTIVITY OF EGYPTIAN COTTON UNDER IRRIGATION CONDITIONS WITH AGRICULTURAL DRAINAGE WATER.

This investigation was conducted at North Nile Delta area, Kafr El-SheikhGovernorate, Egypt, during the two successive seasons 2022 and 2023, on Egyptiancotton cultivar (Super Giza 94), to study the effect of using agricultural drainage water assource of irrigation water on the yield and production which due to redness of leaves,failure of cotton bolls to open and reduce cotton total yield .So, the current work focusedon assessing agricultural drainage water with potassium and boron fertilizers under thisabiotic stress condition, focusing on their impact on chemical constituents, photosyntheticpigments, yield and anatomical features. Six treatments were evaluated, including variouscombinations of potassium sulphate applied through soil and foliar methods and foliarboron on cotton plants. The treatments were T1: Soil addition of potassium sulphate at arate of 24 units K2SO4 fed 1- , which is the recommended rate for cotton cultivation,T2:Soil addition of potassium K2SO4 at a rate of 18 units fed-1+ foliar application ofpotassium citrate solution at a rate of 6 units K2O fed-1, T3: Soil addition of K2SO4 at arate of 24 units /fed-1+ a foliar application containing 60 mg of boron fed⁻¹ T4: Soiladdition of potassium K2SO4 at a rate of 24 units / fed-1+ foliar application at a rate of120 mg of boron, T5:T2+ foliar application of 60 mg of boron, T6:T2+ foliar applicationof 120 mg of boron. The experiment design was Randomized Complete Block Design(RCBD) with three replicates. Results indicated the possibility of producing cottoneconomically by using agricultural drainage water for irrigation, potassium and boronsignificantly enhanced the nutrient composition in leaves, particularly increasingnitrogen, phosphorus and potassium levels, which positively influenced photosyntheticpigment concentrations.