Field experiments were conducted at Rice Research and Training Center, Sakha, Kafrelseikh Governorate, Egypt during two summer seasons 2010 and 2011 to study the influence of integration between compost and urea fertilizer on yield and its components of Sakha 105 rice cultivar as well as nitrogen uptake in rice grains and soil organic matter percentage. The treatments were (0, 5 ton compost/ ha, 165 kg N/ha, 5 ton compost + 55 kg N/ha and 5 ton compost + 110 kg N/ha).
The results revealed that compost and mineral nitrogen (urea) alone or in combination recorded increasing significant values in number of panicles/hill, number of filled grain/panicle, 1000 grain weight,grain and straw yields, nitrogen uptake and soil organic matter percentage compared with the control treatment (without fertilization) except the number of unfilled grain/panicle which recorded significantly decrease.
The results, also, showed that compost application at rate of 5 tons plus 110 kg N/ha gave the highest values of number of panicle/hill, number of filled grains/panicle, 1000 grain weight, grain yield, straw yield, nitrogen uptake in grains and soil organic matter percentage in both seasons.
The control treatments (without fertilization) recorded the lowest values in all traits as well as yield components, grain yield, straw yield, nitrogen uptake in grain and soil organic matter percentage except the number of unfilled grain/panicle which recorded the highest values in both seasons.
In both seasons the following treatments of 165 kg N/ha, 5 ton compost plus 55 kg N/ha and 5 ton compost plus 110 kg N/ha didn't significantly differ in its effect on the number of filled grains/panicle.
In both compost application at a rate f 5 tons alone or in combination with 110 kg N/ha gave the same 1000 grain weight without significantly differences with 165 Kg N/ha treatment in the second seasons.
The percentage of soil organic matter was increased with addition of compost either alone or with different levels of nitrogen which did not significantly differed in its effect on the percentage of soil organic matter.
From the results under the conditions of this study, it could be concluded that application of 5 tons compost plus 110 kg N/ha produced the highest grain and straw yields and is recommended as an economic treatment for increasing grain yield of rice.