FOLIAR NUTRITION OF NITROGEN AND POTASSIUM FOR OPTIMIZING THE PRODUCTIVITY AND ENHANCING BRIGHT GRADE LEAF PRODUCTION OF FCV TOBACCO IN KLS

Abstract

Among the major nutrients, nitrogen and potassium are very important and required in larger quantities for not only getting higher cured leaf productivity but essential for proper ripening, desired cured leaf quality, smoke chemistry, bright grade production and high burn rate in FCV tobacco. The poor uptake of N and K owing to various biotic and abiotic stresses has lead to poor grade out turn, immature and J style Tobacco resulting in low grade production and economic losses to the growers. Given the vagaries in climate and weather conditions apart from the biotic stresses experienced in the rainfed farming situations of KLS, foliar feeding of nutrients appears to be the ideal option for maintaining the desired N and K nutrient levels in the tobacco plant for realizing optimum productivity and quality leaf production. Field experiment were conducted during 2012-12 and 2013-14 crops seasons to evaluate the foliar nutrition of N and K using Potassium Nitrate and Ammonium sulphate + Sulphate of Potash sources on the cured leaf productivity, bright grade production, cured leaf K content and leaf quality parameters on red sandy loam soils in KLS. Potassium Nitrate and Ammonium sulphate + SOP (sprayed twice at 45 and 55 DAT @ 2%) increased the cured leaf productivity by 9.2 and 9.8% and greatly enhanced the bright grade production by 13.4 and 15.7% respectively compared to the control plot. Further the foliar applications also significantly improved the cured leaf K (by 14.8-15.9%), which is highly desirable in flue cured tobaccos for better leaf combustibility, burn rate and reducing the harmful smoke constituents. The cured leaf quality parameters were not altered by the foliar treatments and were in the acceptable range. The two years study has clearly indicated that the foliar application of N and K can greatly enhances the bright grade leaf production, productivity and cured leaf K in the rainfed tobacco farming of KLS.