Abstract

                                Nitrogen and Phosphorus are two of the most important nutrients for crop production. Many compound fertilisers containing these two nutrients in various proportions have been manufactured under different names by the Fertiliser Industry. Several compound fertilisers like ammonium phosphate, nitrophosphate and others under different proprietory names have been put in the market. Experiments conducted with ammonium phosphate (Anon., 1945-48) at Aduthurai and Pattukkottai during the Kuruvai, Thaladi and Samba seasons have shown that there was no signi- ficant difference between ammonium phosphate and ammonium sulphate-. cum-super application on paddy yields. At the Paddy Breeding Station, Coimbatore (Anon., 1964) another compound fertiliser called "Engrais" Fertiliser (containing 8-3 per cent N and 14 per cent P₂O) was compared against ammonium sulphate-cum-super application and it was found to be inferior to the ammonium sulphate-cum-super combination on equal N and P₂O, basis for paddy. However, according to Zemite (1963), the compound fertilisers produce about the same yields as combinations of single fertilisers supplying equivalent amounts of nutrients. Recently, the Neyveli Lignite Corporation has developed a "Complex Fertiliser". The effect of this "Neyveli Complex Fertiliser " on paddy yield and also on the soil (Cauvery alluvium) was studied at the Regional Research Station, Aduthurai for three years from 1962-63 to 1964-65 and the results are presented.

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