Integrated management of Azolla, vermicompost and urea on yield of and nutrient uptake by rice and soil fertility

Field experiment was conducted to study the effect of integrated management of fertilizer N, vermicompost and Azolla on grain yield, nutrient uptake and soil fertility in a clayey soil for three years (1999–2001). The highest grain and straw yields were recorded with the application of 60 kg N ha−1 plus Azolla. The combined application of fertilizer N, vermicompost and Azolla sustained the productivity even at lower rate of fertilizer N application. The highest N, P and K uptake was also recorded with the application of 60 kg N ha−1 plus Azolla treatment. Moreover, the soil organic carbon, available N, P and K content increased with the application of fertilizer N alone and in conjunction with vermicompost or Azolla compared with control.