Response of Sugar Beet (Beta vulgaris L.) to Potassium and Sulphur Supply in Clayed Soil at North Delta, Egypt

THE SUGAR beet (Beta vulgaris L.) cultivar “Farida” was grown on a clayed soil at Agricultural Research Station, Agricultural Research Center, Egypt, during 2011/2012 and 2012/2013 years. The aim of this study is to study growth, yield and quality response of sugar beet cultivar "Farida" to three potassium rates (12, 24 and 48 kg K₂O/feddan) (feddan (fed)= 0.42 hectare) and three sulphur rates (0, 125 and 250 kg S/fed) in clayed soil at North Delta, Egypt.
Application of potassium fertilizer at the rate of 48 kg K₂O/fed resulted in a substantially increase in leaf area index (LAI) and dry matter accumulation (g/plant), root length (cm), root diameter (cm), root weight (g), root yield (ton/fed), top yield (ton/fed), total sugar (%), concentration of K, alkalinity coefficient, extraction of white sugar (%), losses sugar (%) and white sugar yield (ton/fed) compared with the rate of 12 kg K₂O/fed in the two seasons. The inverse was true in juice purity (%) in the first season. The rate of 24kg K₂O/fed was statistically at par with the rate of 48 kg K₂O/fed in all the mentioned traits in both seasons. Potassium fertilizer rate had no significant effect on root/top ratio, concentration of Na and a-amino nitrogen (meq/100g) in both seasons and the percentage of juice purity (%) in the second season. Increasing sulphur rate from 0-250 kg S/fed significantly increased dry weight (g), LAI , root dimensions (length and diameter) (cm), root weight (g), top yield (ton/fed), root yield (ton/fed), gross sugar (%), white sugar (%), juice purity (%) and sugar yield (ton/fed) in both seasons. Application of sulphur fertilizer improved juice purity by decreasing impurities (K, Na and a-amino-N) in roots and, loss sugar (%) in the two seasons. Sugar beets received 250 kg S/fed produced the highest root and sugar yield (ton/fed). The interaction between potassium and sulphur rates had a significant effect on root and white sugar yields/fed. The maximum root and white sugar yields were achieved from beets received 24 or 48 kg K₂O along with 250 kg S / fed in both seasons. It can be concluded that application of 24 kg K₂O plus 250 kg S /fed was the recommended treatment for optimum root and extractable white sugar yield per unit area at Kafrelshiekh Governorate, Egypt.