Effect of Potassium Humate and Nitrogen Fertilization on Yield and Quality of Sugar Beet in Sandy Soil

Abstract

Two field experiments were conducted at Wadi El-Natrun, El-Bahira Governorate, (latitude of 30.480 N and longitude of 30.500 E) in 2015/2016 and 2016/2017 seasons to study the effect of potassium humate and nitrogen fertilization and its impact on yield and quality of sugar beet sown in a sandy soil. The present work included twelve treatments, which were the combination of four potassium humate levels as soil additives (without, 4, 8 and 12 liter /fed) and three nitrogen rates (80, 100 and 120 kg N/fed). the treatments were arranged In strip plot design with four replicates. Potassium humate levels were occupied the vertical plots, while nitrogen rates were represented in horizontal plots. Results show that soil application of 8 and/or 12 l potassium humate/fed significantly exhibited higher values of leaf area index (LAI), root diameter, root and foliage fresh weight/plant, sucrose%, and quality index as well as extractable sugar%, root and sugar yields/fed in both seasons. Moreover, root potassium, sodium, a-amino N contents, alkalinity coefficient and sugar lost to molasses% were insignificantly affected by the studied potassium humate levels.Increasing nitrogen fertilizer from 80 up to 120 kg/fed positively enhanced LAI, root diameter, root and foliage fresh weights/plant in both seasons. Whilst, the highest sucrose, extractable sugar percentages, sugar and root yields/fed, quality index and alkalinity coefficient were obtained by the application of 100 kg N/fed. On the other hand, higher values of sugar lost to molasses% and non-sucrose components (K, Na and a-amino -N) were detected in beets fertilized with 120 kg N/fed. Based, under conditions of the present work, application of 8 1/fed potassium humate and fertilized with 100 kg N/fed could recommend obtaining the highest root and sugar yields/fed.