FIELD WATER MANAGEMENT AND N-RATES TO SAVE WATER AND CONTROL IRON TOXICITY IN LOW LAND RICE

Poor level of development of lowlands in West Africa, epitomized with bad water management generates favorable conditions for occurrence of iron toxicity which is responsible for limiting yields of lowland rice. Field trial was conducted in 2009, 2010 and 2011 to evaluate the effect of water and nitrogen management on iron toxicity and yield of lowland rice in the Bida, Niger State, Nigeria. Treatments imposed were: (1) Continuous flooding with 5 cm water head from transplanting to hard dough stage. (2) Alternate 30 days flooding with 5 cm water head ? 7 days drainage - 30 days flooding ? 7 days drainage ? 30 days flooding -7 days drainage and flood up to hard dough stage. (3) Alternate 60 days flood with 5 cm water head - 7 days drainage ? 30 days flooding ? 7 days drainage and flood up to hard dough stage. (4) Alternate 90 days flooding with 5 cm water head ? 7 days drainage ? flood up to hard dough stage. The N-rates applied were: 40 (control), 60, 80 and 100 kg N ha-1. Treatments were replicated four times and data obtained were statistically analyzed using SAS statistical package. Results obtained showed that irrigation and N-rates had significant influence (P