Impact of Nitrogen Levels on Associated Weeds, Fodder Ability and Grain Protein Content of Dual-Purpose Wheat

Abstract

ABSTRACT: Studies were carried out to see the response of dual-purpose wheat to different nitrogen levels i.e. 0, 50, 100, 150 and 200 kg N ha-1 in cut (for forage and grain purpose) vs. uncut (for grain only) treatments at the Agriculture Research Institute, Dera Ismail Khan, Pakistan during the years 2009-10 and 2010-11. The results revealed that maximum number of days to heading (123.5 and 124.5), plant height (117.7 and 116.6 cm), grain protein content (11.59 and 12.47%), fresh forage yield (2,646 and 2,956 kg ha-1) and grain yield (4,631 and 4,489 kg ha-1) were recorded in plots that received either 150 or 200 kg ha-1 nitrogen respectively and vice-versa. The data indicated higher values for number of days to heading in cut (124.9) as compared to uncut plots (118.9). Uncut plots attained maximum plant height (112.4 cm), leaf area index and duration at 112 DAS (2.82 and 45.2 respectively) and crop growth rate (15.44 g m-2 day-1). Significantly lower fresh and dry weed weights were recorded in cut plots as compared to uncut plots while different nitrogen levels did not affect them significantly. Grain protein content was slightly lower in cut plots (11.11%) under different levels of nitrogen as compared to uncut plots (11.24). Dual-purpose wheat resulted in a higher benefit cost ratio as compared to grain-only wheat using higher nitrogen levels. It was concluded from the studies that either 150 or 200 kg ha-1 nitrogen can be profitably used for enhancing dual-purpose wheat productivity.