A DISSERTATION SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE IN SOIL SCIENCE AND LAND MANAGEMENT OF SOKOINE UNIVERSITY OF AGRICULTURE. MOROGORO, TANZANIA
A comprehensive study was conducted on soils of Mvumi Village, Kilosa District, Tanzania to investigate the effect of water and nutrients on the growth and yield of rice so as to improve rice production by manipulating water and nutrients. Soil characterization, fertility evaluation and pot experiment were conducted. The soils of the study area were classified respectively as Ustic Endoaquerts and Haplic Vertisols in the USDA Soil Taxonomy, and World Reference Base for Soil Resources. Nitrogen (N), Phosphorus (P) and Potassium (K) were deficient in all sampled fields whereas micronutrients were adequate except for Zn which was low. A pot experiment was set to test the effect of water and nutrients on performance of rice. The experiment was laid in a split plot design with two water management systems (SRI= Alternate wetting and drying, FLD= Continuous flooding) as main factor and five nutrient combinations (N0P0K0S0, N400P0K0S0, N400P80K0S0, N400P80K50S0, N400P80K50S40) as sub-factor. Nutrients and water had significant effect on growth, yield and nutrient content of rice. Overall, treatment N400P80K50S40 had significantly (P < 0.05) higher number of tillers (12.44 tillers plant-1), plant height (98.86 cm), grain yield (26.26 g plant-1) and biomass yield (23.57 g plant-1) as well as total P (0.27%), K (1.07%) and S (0.15%) concentrations in biomass shoot than other treatments. On the other hand, the highest number of tillers (11 tillers plant-1), grain yield (20.74 g plant-1), biomass yield (17.37 g plant-1) and S (0.13%) concentration in biomass shoot were recorded in SRI while the highest plant height (95.47 cm), N (2.02%), P (0.24%) and K (0.89%) concentrations in biomass shoot were recorded in FLD. The results of interaction of nutrients and water showed that, grain yield increased significantly (P < 0.05) from 4.71 g plant-1 to 27.37 g plant-1 in FLD + N0P0K0S0 and SRI + N400P80K50S40 , respectively.