Abstract
The study was conducted to investigate the effect of plant density , methods of nitrogen fertilizer application , and levels of nitrogen fertilizers on yield and yield components and quality traits of cotton, cultivar (Lachata). The study included field experiment for the summer season 2007 in Al-Rahmanya village, Mosul city. Split-split plot design in RCBD with three replications was used .The experiment included two planting spaces between rows 60 , and 75 cm and two methods of nitrogen fertilizer application The first method used half the quantity at thinning and second half at blooming .The second method used one third of the quantity of fertilizer at thinning and the rest two thirds at blooming and four levels of nitrogen fertilizers Zero , 108 , 216, and 324 kg N/ha. The results indicated that the spacing of 60 cm between rows was significantly superior compared with the spacing 75 cm in the trait of total cotton yield and Lint cotton. The spacing between rows was not significantly in the rest of the yield traits , components , and quality traits. The method of nitrogen fertilizer application had no significant impact on the yield traits , components and quality traits except for the seed index and total cotton yield of plant in which the second method of application was significantly superior over the first Significant differences show in the levels of applied nitrogen fertilizers in all yield traits and its components except for the percentage of ginning of cotton. The levels of applied nitrogen fertilizer didn’t differ significantly in all quality traits .
