EFFECT OF METHOD AND TIME OF MICRONUTRIENTS APPLICATION ON SUGARBEET PRODUCTIVITY UNDER TWO NITROGEN FERTILIZER SOURCES

摘要

Two field experiments were carried out during the two successive seasons 2015/2016 and 2016/2017 to study the effect of method and time of micronutrient application on sugar beet productivity under two nitrogen fertilizer sources. Our results in-dicated that nitrogen fertilizer source had no signifi-cant effect on root and top weights/plant and yield/faddan, sugar yield, sucrose%,extractable sugar% and alkaline coefficient in both seasons as well as on sugar losses in molasses only in the first season. Urea as nitrogen fertilizer source recorded the highest values of most traits but the differences between urea and calcium nitrate did not reach the 5% level of significant. Time and method of micro-nutrients application significantly affected all stud-ied traits in both seasons, except sugar yield/fad in the first season. Application of micronutrients at 25%of recommended dose as basal+ 75% of rec-ommended dose as foliar spray three times at 60,75 and 90 DAS (b3)recorded the highest values of all studied traits without significant differences in most cases with (b6) treatment(50% of recommended dose as basal+50% of recommended dose as foliar spray three times at 60,75 and90 DAS.The interac-tion between the two factors under study had no sig-nificant effect on all studied traits in both seasons. It could be concluded that application of micronutri-ents at 25%of recommended dose as basal+75 %of recommended dose as foliar spray three times at 60,75 and 90 DAS under any source of nitrogen fer-tilizer could be recommended for maximizing sugar beet yields and quality at the same conditions of this research.