Apiou, David2025-06-272025-06-272024-10Apiou, D. (2024). Straw and water management in rice production systems in lira district, Ugandahttps://hdl.handle.net/20.500.12504/2542xiii, 71 p.About half of the world's population is fed by rice, and the crop produces about one billion tons of straw residue annually. In fact, rice production is anticipated to rise dramatically in the near future to feed the world's expanding population. On the other hand, water which is a major factor in rice production is becoming scarcer and more competitive on a global scale. Almost two third of water supply has been used for irrigated agriculture and roughly thirty percent of all irrigated land is used for rice production, making it the most common irrigated crop in agriculture. These therefore make rice straw management and water management regimes in rice production a global challenge. Improper management of rice straw and water management regimes limit rice production. The main objective of the study was to identify the most efficient and effective rice straw disposal and water management strategies for sustainable rice production. The specific objectives were: 1) to determine the effects of straw management on rice grain yield in Lira district, Northern Uganda, and 2) to assess the effects of water management regimes on rice grain yield in Lira district, Northern Uganda. Both experiments were conducted in Itek Sub County, Lira district, Northern Uganda during the second and first season of 2021 and 2022 respectively. The experimental design for the two experiments were randomized complete block design arranged as split plots with three replications. For objective 1, a total of four treatments were evaluated, which included subjecting two rice varieties (i.e. PR1 07 and Namche 5) under two rice straw management regimes (i.e. rice straw incorporation (RRI) and rice straw removal (RRR)) for their effects on rice growth and grain yields. In the second objective, a total of six treatments were evaluated whereby the effects of alternate wetting and drying (AWD), continuous flooding (CF), and continuous drying (CD) on grain yield of K5 and PRl 07 rice varieties were assessed. The result of the assessment revealed that incorporation or removal of rice straw had minimal effect on rice growth, biomass and yield with mean straw and yield of 3.2 t/ha and 2.4 t/ha respectively, irrespective of season and treatment. However, rice growth biomass and yield depended on variety and season. Except for height, the average number of tillers (11.6) and number of panicles (121.6) produced by PR107 rice variety was significantly higher than that produced by Namche 5 (number of tillers= 8.5), number of panicles= 69.0). The height of Namche 5 variety (0.73m) was significantly higher than that of PR1 07 (0.69 m). The results of yield assessment further revealed that the rice variety PR107 produced a significantly higher tonnage of straw (4.2 t/ha) and grain yield (3.3 t/ha) than Namche 5 straw (2.2 t/ha) and grain yield (1.5 t/ha). For both variables, the weight of rice straw and rice grain yield that were obtained in the second season were significantly higher than that recorded in the first season. Similarly, the sh1dy showed that various water management regimes had no significant effect on growth and yield of two rice varieties. There was no significant difference in grain yield among treatments (P>0.05). Treatment with CD realized average highest grain yield across seasons. K5 performed better than PR107 under scarce water resource (first season). In conclusion, the greatest grain yield under CD treatments for both seasons present farmers a chance to enhance rice grain output despite limited irrigation water due to climate change.enRiceYieldsResiduesManagementAgricultural wastesWater use in agricultureUgandaLira DistrictIrrigationThesis