IMPROVING THE PRODUCTIVITY AND SUGAR RECOVERY OF CANE BY POTASH NUTRITION UNDER DIFFERENT PLANTING METHODS

Abstract

Potassium-nutrition is a subject of great consideration, as research has revealed its importance in increasing sugar recovery in sugarcane. While it cannot achieve its genetic expression of yield without proper planting technology. Therefore, the present study was conducted to optimize the planting method and K level to improve the yield and sugar recovery of sugarcane at University of Agriculture Faisalabad in 2014-2016. Treatments comprised of four planting methods viz. i) 90 cm spaced pits with a diameter of 90 cm, ii) 90 cm spaced pits with a diameter of 90 cm in diagonal fashion, iii) 90 cm spaced double row strips and iv) 120 cm spaced trench planting in combination with four K nutrition levels i.e., 0, 100, 200 and 300 kg/ha K2O. Results revealed that K application improved the growth, cane yield and sugar recovery irrespective of planting method. However, maximum number of tillers were recorded in sugarcane sown in diagonal pit planting at 90 cm with 100 kg/ha K2O. Likewise, Leaf area index and net assimilation rate were substantially improved with K application in all planting methods. More cane weight (15%) was obtained at sugarcane sown in 120 cm spaced trenches with 200 kg/ha K2O during both the years. Stripped cane yield was maximum in diagonal pit planting at 90 cm with 100 kg/ha K2O (113.7 t/ha) during the plant crop year and diagonal pit plantation + 200 kg/ha K2O (98.22 t/ha) during the ratoon crop year. Likewise, maximum potassium use efficiency (KUE) i.e. 99.5 and 88.2 kg /kg were recorded in planting of sugarcane in diagonal pits at 90 cm with 100 kg/ha K2O during plant crop year and 120 cm trenches +100 kg/ha K2O during the ratoon crop year, respectively. Sugar recovery was also enhanced by all the K nutrition levels over control. The cultivation of sugarcane in 90 cm spaced pits with the supplementation of potash at 100 kg/ha gave the maximum sugar yield of 15.8 t/ha in plant crop year and 13.2 t/ha in the ratoon crop year. The combined economic analysis over two years (plant + ratoon year) revealed that sugarcane planting was more beneficial at 120 cm spaced trenches, with 100 kg potash/ha (3678$); which was followed by 90 cm diagonal pit plantation +100 kg/ha K2O which gave the combined benefits of 3611$. Sugar cane may be planted in 90 cm diagonal pits and 120 cm spaced trenches with 100 kg/ha potash to improve the cane yield and sugar recovery