Abstract
The factorial pots experiment was conducted in order to investigate the effect of some herbicides ( Trifluralin 2.4 , 3.2 , Focus ultra 1,2 L/ ha) with check treatment and nitrogen fertilizer ( 0.0 , 40 , 80 kg N / ha) on growth of nodulation in 2005-2006 season at Agric and Forestry college , Mosul Univ . The results indicate that treflan had effect negtively on number and weight of nodulation but focus ultra had positive result on it . Weight of nodulation had increased at 80 kg N / ha but numbers was reduced . The best results obtained with interaction between focus ultra 2 L / ha and 40 kg N / ha fertilization or 1 L/ ha of the same herbicide with 80 kg N / ha which gave good growth of nodulation on root lentil crop .
