Utilization of industrial waste aqueous ammonia for irrigated forage sorghum production

摘要

Sorghum is one of the water- and nutrient-use efficient crops raised in dry regions worldwide. A3 x 3 split-plot experiment in randomized complete block design was conducted to study the effects of petroleum refinery waste aqueous ammonia (NH3) on irrigated fodder sorghum for two consecutive growing seasons. The main plots consisted of 0 (control), 40, and 80 kg N ha~(-1), respectively, and the injection depths (surface 15 cm, and 20 cm depth) were assigned to sub-plots. A significant effect of NH3 on both fresh and dry biomass production was observed where the highest yield was recorded from the 80 kg N ha~(-1) than the control and 40 kg N ha~(-1), respectively. Sorghum biomass yield increased most when NH3 was injected at 20 cm depth as compared to other depths. Biomass nutrient content and nitrogen-use efficiency were increased when 80 kg N ha~(-1) was applied as compared to the control. The critical limit of K:(Ca+Mg), above which the tetany risk increases, did not exceed in sorghum biomass byNH_3 fertilization. Results suggested that industrial waste NH_3 equivalent to 80 kg N ha~(-1) injected at 20 cm depth can be a sustainable approach to fertilize irrigated sorghum growing as a forage crop.