The role of Azolla cover in improving the nitrogen use efficiency of lowland rice

摘要: The development of management techniques to improve the poor N use efficiency by lowland rice (Oryza sativa L.) and reduce high losses has been an important focus agronomic research. potential Azolla cover in combination with urea was assessed under field conditions Laguna, Philippines. Two on-station experiments were established 1998–1999 dry season eight on-farm per carried out 2000–2001 wet seasons. Treatment combinations consisting levels applied alone or combined evaluated respect floodwater chemistry, 15N recovery, crop growth, grain yield. A full on surface at time application prevented rapid large increase pH temperature. As a consequence, partial pressure ammonia (ρNH3), which is indicator NH3 volatilization, significantly depressed. recovery higher plots covered where total ranged between 77 99%, aboveground (grain straw) 32 61%. tiller count Azolla-covered increased 50% more than uncovered all levels. Consequently, yield likewise improved. Grain yields from 16 trials as much 40% lower rates (40 50 kg N ha−1) 29% (80 100 kg N ha−1). In addition, response treatments comparable that obtained without cover. Thus, using can be alternative practice worth considering means volatilization efficiency.