Oommen, MSadanandan, NMohammed Kunju, USasidhar, V KKAU2019-07-172019-07-171977Agricultural Research Journal of Kerala, 15(1), 24-28.http://krishikosh.egranth.ac.in/handle/1/5810115094An investigation was carried out at the Model Agronomic Research Station, Karamana during the second crop season 1975 to study the comparative efficiency of different slow release nitrogen sources on growth, yield and yield contributing attributes of rice variety Jaya. All the slow release nitrogen sources were superior to ordinary untreated urea. Highest percentage of productive tillers was recorded by neem cake blended urea followed by AM treated urea. The weight of panicle was maximum in AM treated urea followed by neem cake blended urea. AM treated urea also gave the highest number of spikelets per panicle. Thousand grain weight, yield of grain and straw were maximum in AM treated urea followed by neem cake blended urea. AM treated urea gave an average yield of 4687kg/ha followed by neem cake blended urea which gave 4296kg/ha. The minimum grain yield of 2688kg/ha was given by untreated urea.ennullArticle