Abstract

Field experiment was conducted at the agricultural experimental farm of agronomy department – Collage of Agriculture – University Of Anbar, during the two winter seasons of 2015/2016 and 2016/2017, to study the effect of amino acids with different concentrations on the yield and yield components of three wheat varieties. The experiment was performed in split - split plot using RCBD in three replicates, where amino acids plots (Tryptophane, Arginine and Tyrosine) were assigned to the main plots, subplots were occupied by acid’s concentrations (0, 100, and 200 ml L-1 each), while the varieties (Alrashed, Tamoz2 and Abu Ghraib3) occupied the sub-subplots. The Obtained results showed that the amino acids significantly affected the studied traits, where applying Tryptophan increased spike length in the 1st season and increased the weight of 1000 grain in 2nd season. Spraying Tyrosine gave the highest average of spikes number per m-2 in the 1st season, grains number per spike 47.33 and 49.94 grain per spike for the both seasons and therefore increased the grain yield 5.92 and 6.83 t.ha-1. Whereas amino acids didn’t show any significant effect on the harvest index. Amino acids concentrations had a significant impact on traits such as spike length, grains per spike, weight of 1000 grain and grain yield. Concentration of 200 mg L-1 gave highest grain yield value reached 6.27 and 7.16 t ha-1 for both seasons respectively, while had no significant effect on the harvest index. Used varieties differed significantly for studied traits in both seasons, Alrashed variety was superior in traits like spike length, number of grain per spike (47.86 and 49.19), 1000 grain weight 34.12 and 35.49 gm, grain yield 6.32 and 7.09 t ha-1 and the harvest index for both seasons respectively. However Abu Ghraib3 variety was superior for spikes per square meter 507.0 and 523.9 spike.m-2.