Integrating crop management of rice is the main strategy for maximizing rice productivity in Egypt. Optimizing phosphorous application will ensure high productivity of rice and soil sustainability. Two field experiments were conducted during 2010 and 2011 seasons at the Farm of Sakha Agriculture Research Station, Kafr-El Sheikh Governorate, Egypt. The soil texture was clayey. EC was 1.6 and 1.5 dS/m during 2010 and 2011, respectively. The eleven suggested treatments studied the response of Giza 178 rice variety to various alternates of phosphorous management namely; control(1), basal application the rate of 54 kg P2O5/ha (2), Diammonium phosphate (DAP) spray with the concentration of 2% at mid tillering stage (MT) (3), Potassium triphosphate (KTP) spray at MT 2% (4), DAP spray 2% at panicle initiation (PI) (5), KTP 2% at (PI) (6), DAP spray 2% at booting stage (BT) (7), KTP2% at (BT) (8), basal application of phosphorous+ 2%of DAP at BT(9), basal application of phosphorous + 2% of KTP at BT(10) and DAP spray at the concentration of 2% at the three growth sage (11). The results of this study can be summarized as follows. Phosphorous application treatments either basal or foliar and their combination at beginning of boot growth stage were significantly increased P leaf content and its uptake. Also, phosphorous application significantly improved growth parameters at heading date viz; LAI, dry matter production, tillers number/hill and plant height. Flag leaf characteristics, i.e. flag leaf area, dry weight of flag leaf and chlorophyll content were significantly improved by phosphorous either basal or foliar spray as combination particularly, at booting stage. Yield components and rice grain yield were significantly improved by phosphorous application involving basal, foliar application and their combinations at booting growth stage were found to the most. Basal application of phosphorous+ 2%of DAP at BT and basal application of phosphorous+ 2%of KTP at BT were found to be the most effective treatments , whereas they were comparable regarding all above mentioned traits and recorded the maximum values of them. Furthermore, DAP spray at three growth stage at mid tillering stage+ panicle initiation + beginning of booting stage and basal application treatments were comparable regarding rice grain yield but the basal application economically surpassed it. From economic point of view, the treatment of basal application of recommended phosphorous+ 2%of DAP at BT was the best and it could be recommended under similar conditions.

An experiment was carried out at the Experimental Farm of Rice Research and Training Center (RRTC), Sakha, Kafr El-Sheikh, Egypt, during 2011 and 2012 seasons. The experiment was laid out in a split plot design with four replications. The main plots were devoted to the nitrogen level 220kg N/ha in form of urea (46.5% N). The sub-plots were allocated to the six times of nitrogen application to assess the effect of six nitrogen application treatments, viz., T_1: (2⁄(3 ) as B ( basal ) + 1⁄3 at PI ( panicle initiation)), T_2: (1⁄3 as B + 1⁄3 at MT (mid-tillering) + 1⁄3 at PI.)), T_3:(1⁄2 as B + 1⁄4 at MT + 1⁄4 at PI.)), T_4:(1⁄4 as B + 1⁄4 at MT + 1⁄4 at PI + 1⁄4 at BT (booting)), T_5:(1⁄4 as B + 1⁄4 at MT + 1⁄4 at BT + 1⁄4 at CH (complete heading)), and T_6:(1⁄4 as B + 1⁄4 at MT + 1⁄4 at PI + 1⁄4 at F ( flowering)) on morpho-physiological attributes and grain yield of Egyptian hybrid rice (1) under broadcast seeded-rice. The results revealed that nitrogen levels caused significant increases in all morphophysiological attributes and grain yield of Egyptian hybrid rice (1), except for number of primary branches/panicle, number of panicle/m², panicle weight and 1000-grain weight in both seasons. Leaf area index and dry matter production at flowering were significantly increased in first and second seasons, respectively, Increasing N-level up to 220kg N/ha significantly increased number of unfilled grains/panicle and straw yield t/ha. In addition, application of 165kg N/ha produced the highest values of number of filled grains/panicle, grain yield t/ha and harvest index in both seasons. Moreover, It was observed that the highest estimated values of dry matter production at panicle initiation and straw yield; and the lowest number of panicles/m² were recorded in the first treatment (T_1), without significant differences with the 〖(T〗_(3 )) and 〖(T〗_(5 )) treatments in both seasons. The highest dry matter production at flowering, LAI at flowering, chlorophyll content in flag leaf, days to 50% heading, plant height at harvest, number of primary branches/panicle, panicle weight, heaviest 1000-grain weight, harvest index and grain yield were exhibited in 〖(T〗_(6 )) in both seasons, The interaction between nitrogen levels and time of nitrogen application had significant effect on dry matter production ( g/m²) at panicle initiation, leaf area index at both panicle initiation and at flowering, chlorophyll content in flag leaf and number of tillers/m², number of filled grains/panicle in both seasons and number of unfilled grains/panicle in the second season. From the obtained results, it could be recommended that splitting of N-fertilizer application with the rate of 165 kg/ha in four equal doses i.e. as basal application, mid-tillering, panicle initiation and at the flowering stages were played a remarkable role for achievement of high yield production from Egyptian hybrid (1) rice genotype, when it grown under broadcast seeded rice under normal soil in Egypt. Elkhoby, W. M. et al. 1260