Abstract

Field experiments were conducted at Tamil Nadu Agricultural University, Coimbatore to develop suitable integrated nitrogen management practice for wet seeded rice. Different sources of nitrogen integrated were Sesbania rostrata as green manure (GM), Azolla (Az) as biofertiliser and prilled urea as chemical fertiliser. Integrated use of green manures and biofertilisers along with chemical fertiliser enhanced the growth and yield attributing characters viz. tillers m², LAI, number of panicles m³, number of filled grains per panicle; nutrient uptake and ultimately rice grain yield. Application of GM+ Az,,+PU, produced comparable yields with GM +AS+ PUs the highest level tried. Inoculation of Azolla at 1.0 t ha along with urea resulted in comparable yield with that of succeeding level of urea, but with no Azolla, suggesting a a saving of 25 kg N ha of chemical fertiliser.

Keywords: Integrated N management, Azolla, Sesbania rostrata.