EFFECT OF SOURCE AND LEVEL OF NITROGEN FERTILIZER ADDING SUB SURFACE ON GROWTH AND DISTRBUATION OF TOMATO PLANT ROOTS GROWN IN DESERT LANDS

A field experiment conduct in AL-Berjesia Researches Station during the season of 2016 – 2017 in Loamy Sand soil classified as Typic Quartezi Pssament in west desert area from south of Iraq in Basrah government to study the effect of Urea and DAP as a source of Nitrogen fertilizer and four Nitrogen levels ( 0 , 90 , 180 and 270 Kg N ha -1 ) applied sub surface through irrigation water by drip system every 7 days on tomato roots distribution hybrid verity ( Hottouf ). Tomato seeds seedling in 1/9/2016 in phelien pots , in 15/10/2016 tomato nurses transfer to the field. At the end of growth season in the end of May/2017 profile were made vertically with 70 cm width and 50 cm deep near plant roots on wet face to explain roots distribution and their numbers by using wood rectangle frame ( 70 x 50 ) cm divided to equal squares ( 5 x 5 ) cm using Monolith method. Results showed that rate of 270 Kg N ha -1 through irrigation water by drip system from DAP gate highest roots number ( 243 roots ) in ( 5 – 10 ) cm sub soil surface deep with 25.8 % , and increased roots deeping to ( 45 ) cm with 70 cm horizontally distribution , highest total roots number ( 942 roots ) , whenever another source and all levels of Nitrogen fertilizer from Urea and control treatment gates less roots number and less roots distribution.