Response of Sugar Beet (Beta vulgaris, L) to Irrigation Regime, Nitrogen Rate and Micronutrients Application

Document Type : Original Article

Authors

1 Agronomy Dept., Fac. Agric., Kafrelshiekh University, Egypt.

2 Soils dept., Fac. Agric., Kafrelshiekh University, Egypt.

Abstract

The sugar beet (Beta vulgaris, L) cultivar “Farida” was grown on a clay soil at Water Management Research Station at El-Karada, Kafrelshiekh, Egypt, in 2007/2008 and 2008/2009 seasons, to determine the effect of three irrigation regimes (at 40, 55, 70% depletion of available soil moisture, DAM), two nitrogen rates (75 and 90 kg N/feddan) and four micronutrients treatments (through seed soaking (SS), foliar spraying (FS), (SS+FS) and control) on growth, yields, quality and water relations. Solution of micronutrients contained 2 g from each of Zn SO4 (26% Zn), Mn SO4 (24% Mn), Fe SO4 (20% Fe) and boric acid per liter. Abundance of the available soil moisture significantly increased dry weight/plant, leaf area index (LAI), root diameter, top yield, crop growth rate (CGR) and water consumptive use (WU). The inverse was true in root/top ratio, root length and concentration of gross sugar in roots. Increasing soil moisture level improved juice purity by decreasing impurities (K, Na and a-amino-N) in roots. The plants irrigated at 55% DAM produced the highest net assimilation rate (NAR) and water efficiency use for roots (WUER) and white sugar (WUES) production compared to those irrigated at 40 or 70% DAM. Increasing nitrogen rate from 75 and 90 kg N/feddan significantly increased dry weight, LAI, CGR, root length, root weight, top yield, root yield, concentration of a-amino-N% and Na + K in roots, loss sugar%, sugar yield and WU. The inverse was true in root/top ratio, gross sugar%, white sugar % and juice purity %. Nitrogen rate had slightly effect on WUER and WUES. Application of micronutrients through seed soaking and foliar spraying (SS+FS) produced the greatest dry weight, root/top ratio, LAI, CGR, root length, root diameter, root weight, top yield, root yield, gross sugar%, white sugar % and juice purity %, sugar yield, WUER and WUES. SS was at par SS+FS in most these traits. FS increased concentration of a-amino-N% and Na + K in roots and the most of mentioned traits compared with control. All interactions had a significant effect on root and white sugar yields/feddan. The maximum root and white sugar yields and the best WUER and WUES were achieved from plants irrigated at 55% DAM and received 90 kg N/feddan along with SS+FS It can be concluded that the irrigation at 55% DAM along with 90 kg N/feddan and SS+FS or SS was the recommended treatment for optimum root and extractable white sugar yield per unit area with less water consumptive use at Kafrelshiekh Governorate.

Main Subjects