1Department of Agricultural Microbiology, Tamil Nadu Agricultural University, Coimbatore 641 003.
2Department of Soil Science and Agricultural Chemistry, Tamil Nadu Agricultural University, Coimbatore 641 003.
*Corresponding author: E-mail: skannaiyan@hotmail.com Tel: 91(44)26288181
Performance of immobilized cyanobacteria in terms of nitrogen contribution to rice seedlings as influenced by combined nitrogen was investigated under hydroponic culture condition, using 15N dilution technique. Sugarcane waste immobilized cyanobacteria enhanced nitrogen content of rice seedlings by 28% over the free-living culture. Rice seedlings receiving 15N tagged combined N sources alone exhibited higher atom excess 15N per cent, which was reduced in presence of cyanobacterial inoculation. Sugarcane waste immobilized cyanobacterial inoculation with nitrate-N increased cyanobacteria derived N in rice seedlings but ammonium-N drastically reduced this effect. In terms of total N derived from fertilizers and cyanobacteria, urea and SCW immobilized cyanobacterial inoculation proved very efficient.
cyanobacteria, immobilization, nitrogen transfer, rice seedlings, 15N dilution
