Mahmoud, E., Masri, M. (2009). EFFECT OF NITROGEN RATES AND ITS TIME OF APPLICATION ON PRODUCTIVITY OF SUGAR BEET UNDER SPRINKLE IRRIGATION IN NEWLY RECLAIMED SOILS. Journal of Plant Production, 34(8), 9037-9048. doi: 10.21608/jpp.2009.118855
E. A. Mahmoud; M. I. Masri. "EFFECT OF NITROGEN RATES AND ITS TIME OF APPLICATION ON PRODUCTIVITY OF SUGAR BEET UNDER SPRINKLE IRRIGATION IN NEWLY RECLAIMED SOILS". Journal of Plant Production, 34, 8, 2009, 9037-9048. doi: 10.21608/jpp.2009.118855
Mahmoud, E., Masri, M. (2009). 'EFFECT OF NITROGEN RATES AND ITS TIME OF APPLICATION ON PRODUCTIVITY OF SUGAR BEET UNDER SPRINKLE IRRIGATION IN NEWLY RECLAIMED SOILS', Journal of Plant Production, 34(8), pp. 9037-9048. doi: 10.21608/jpp.2009.118855
Mahmoud, E., Masri, M. EFFECT OF NITROGEN RATES AND ITS TIME OF APPLICATION ON PRODUCTIVITY OF SUGAR BEET UNDER SPRINKLE IRRIGATION IN NEWLY RECLAIMED SOILS. Journal of Plant Production, 2009; 34(8): 9037-9048. doi: 10.21608/jpp.2009.118855
EFFECT OF NITROGEN RATES AND ITS TIME OF APPLICATION ON PRODUCTIVITY OF SUGAR BEET UNDER SPRINKLE IRRIGATION IN NEWLY RECLAIMED SOILS
Agronomy Department, Faculty of Agric., Cairo Univ., Giza, Egypt
Abstract
Two field experiments were conducted at Sedment El-Gabal location, Beni-Sweif Governorate during 2007/2009 seasons to study the response of sugar beet yield and some of its attributes under sprinkle irrigation to different N rates; 100, 120, 140 and 160 kg N/fed and its time of application viz., split application in two equal doses, at 4- and at 8-leaf stage, or in three equal doses,1/3 at 4- leaf stage, 1/3 at 8-leaf stage and 1/3 three weeks later, or dividing the rate into 4 equal doses and added 1/4 at 4- leaf stages, 1/4 at 8- leaf stage, 1/4 three weeks later and 1/4 three weeks after the last. A split plot design with four replications was used, where N rates were allocated in the main plots and time of N application was distributed at random in the subplots.
Results obtained from this study revealed that increasing N rates from 100 up to 160 kg N/fed significantly increased root weight by 16.52% and 24.77%, number of plants at harvest by 4.05 and 2.89 thousand plants/fed and root yield by 7.22 and 8.34 tons/fed in the first and second seasons, respectively. Excessive N rate lowered beet quality in terms of sucrose content, juice purity and extractable sucrose. Extractable sugar yield increased by increasing N rates from 100 to 120 Kg/fed. Such increase amounted to 29.08 % in the first season and 31.97 % in the second one. Additional increasing in nitrogen rate beyond 120 kg N/fed had no significant effect on sugar yield.
Splitting N rate into 4 equal doses significantly increased weight of individual root and number of plants/fed at harvest. Late N application in favour of N splitted into 4 doses gave the highest root yield/fed. On the other hand, early application and splitting N in two equal doses at 4-and at 8-leaf stage improved beet quality traits in terms of sucrose %, purity % and extractable sucrose %.
Splitting 160 kg N/fed into 4 equal doses gave the highest root yield, while splitting 120 kg N/fed into 4 equal doses was recommended for high sugar yield/fed.