RICE PRODUCTIVITY AS AFFECTED BY INTEGRATION OF ORGANIC AND INORGANIC NITROGEN FERTILIZERS

         Two field experiments were carried out at  Etai EL- Baroud Agricultral Research Station  Farm,  Rice Research and Training Center (RRTC ) –Sakha –Kafer El –Sheikh –Egypt, to study the influence of integration of organic and inorganic nitrogen fertilizers  on the productivity of Sakha 101 rice variety in two consecutive seasons (1997 and  1998).  Four organic fertilizer rates were added ( 0, 10, 20 and 30 t/ha ) to the dry soil before flooding, while, nitrogen fertilizer was applied to rice crop at the rates of (0, 48, 96 and144 kg N / ha ) in the form  of Urea (46.5%N) (2/3 basal and incorporated into the dry soil + 1/3, 7 days  before panicle initiation). The main results indicated that increasing nitrogen fertilizer up to 144 kg N /ha and 30 t/ha as organic fertilizer increased plant height, panicle weight, 1000-grain weight, grain and biomass yields while, 20 t / ha as organic fertilizer and 96 kg N / ha were adequate for the highest values of panicle length, number of panicles / hill and number of grains / panicle.  Data also indicated that increasing organic and inorganic nitrogen fertilizer significantly decreased harvest index  and the application of 10 t / ha and 30 t /ha organic fertilizer saves about 48 and 96 kg N/ha,  respectively.   Data also indicated that 20 t / ha  organic fertilizer and 96 kg N / ha  are  adequate for the highest hulling and milling out puts in the two growing seasons. Data concluded that the application of organic fertilizer besides its save some of  the  inorganic fertilizer its improved soil  physical and  chemical properties.