Two field experiments were carried out during 2018 and 2019 seasons at the experimental farm of Sakha Agriculture Research Station, Sakha, Kafrelsheikh, Egypt to study the response of three rice varieties namely; EHR1, EHR3 and Giza178 to examine the possible role of exogenous application of SA and P applications under three irrigation intervals; continuous flooding, irrigation every six days and irrigation every nine days. The experiment was performed in a strip split plot design with three replications. Irrigation intervals were subjected in the vertical plots and the rice varieties were allocated in the horizontal plots. The sub-plots were devoted to chemical treatments.  The main results of the both seasons were summarized as follows; EHR1 gave the longest heading date and the maximum values of number of tillers m^-2, plant height and flag leaf area, EHR3 variety gave the highest values of leaf chlorophyll content, leaf area index, number of total grains panicle^-1, 1000-grain weight and grain yield as well as hulling and milling percentages. Giza178 inbred rice cultivar recorded the highest percentages of filled grains and head rice, while, it gave the minimum values of growth parameters, yield attributes and grain yield. Irrigation every 6 days recorded high water use efficiency with a little reduction in grain yield and save some of irrigation water when SA or P was exogenously applied. Nine days interval saved water by 19.09 % and 18.86 % with grain yield reduction of 13.52 % and 14.41 % in both seasons, respectively.