EVALUATION OF PLACEMENT SITES AND FORMS OF UREA FERTILIZER FOR IMPROVED NITROGEN USE EFFICIENCY IN HYBRID MAIZE CULTIVATION.

Abstract

By using different rates and forms of urea fertilizer, the field experiments were carried out at Department of Agricultural Research, Head Quarters, Yezin and Tatkon Agricultural Research Farm, during the monsoon season of 2017. For improving nitrogen use efficiency of Yezin Hybrid Maize-10 variety, four nitrogen fertilizer rates (0, 71.27, 118.78 and 166.29 kg N ha-1) were applied with two forms of nitrogen fertilizer (Briquette urea and Prilled urea). The 4 x 2 factorial arrangements were assigned in the Randomized Complete Block Design with 3 replications in both experimental sites. Mean effects of applied nitrogen rates on seed yield of maize were highly significant in this study. The highest mean values of seed yield resulted with the rate of 166.29 kg N ha-1 in Yezin (8.14 t ha-1) and Tatkon (11.69 t ha-1). Although, there was no significant effect from forms of urea fertilizer on seed yield, mean seed yields of Briquette urea were generally higher than those of Prilled urea at the same level of applied N rate in both sites. Non-significant interaction was observed between rate and form of urea fertilizer factors in the variation of hybrid maize seed yield. The similar trend was also observed in comparison of agronomic nitrogen use efficiency (AE) of hybrid maize. The AE mean values of 166.29 kg N ha-1 (8.14 and 11.69 t increased seed kg-1 N applied) were significantly higher than those of other two rates of applied nitrogen in Yezin and Tatkon, respectively. The significant effect was observed from forms of urea fertilizer on nitrogen recovery efficiency (RE) in both trials. The RE means of Briquette gave 208.58 in Yezin and 631.43 in Tatkon.