Phosphrous Requirement of Paddy Grown in High Phosphorous Vertisols

Paddy is staple food crop and life too in the world and one of the most important cereals grown in India and occupies second position in cultivation after wheat. India produced 89.13 million tonne of rice from an area of 41.85 million hectare with a productivity of 2130 kg ha-1 during the year 2009-2010. Phosphorus is one of the major nutrients required for production of rice. In soils more than 80% of applied P becomes immobile and unavailable for plant uptake because of adsorption, precipitation, or conversion to organic form. It was observed that the soils under irrigated K.C Canal commands especially under paddy crop are showing high soil available P status. Among the different treatments application of per cent RDP with GM resulted in significantly higher grain yield of paddy in high soil available P vertisols followed by application of 50 per cent RDP only or in combination with FYM @ 5 t ha-1. This shows that even in high soil available P soils application of 50 per cent RDP is required to realize higher grain yield of paddy.