Effect of Tillage Practices and Irrigation Schedule on Soil Quality and Yield of Some Rice (Oryza sativa L.) in Sokoto Rima Flood Plain

Sokoto Rima Flood Plain (SRFP) is located in Sudan Savanna agro-ecology of Nigeria, and is faced with the common challenge of flooding towards the end of the rainy season and widespread drought with high potential for irrigated rice production during dry season. Two year experiment was conducted in the dry season of 2018 and 2019 in a farmer`s field, near the Usmanu Danfodiyo University Teaching and Research Farm, Kwalkwalawa in SRFP, Sokoto State. The treatments consisted of factorial combination of two tillage practices; conventional and reduced tillage, three irrigation schedules; one, two and three days schedule of irrigation and three rice varieties (FARO 44, 60 and 61). Treatments were laid in a split plot design replicated three times, where tillage practices and irrigation schedules were allocated to the main plots while rice varieties to the sub-plots. Data on particle size distribution, bulk density and water retention were simulated by RETC model for Mualem-van Genuchten parameters and for estimating the soil physical quality index (S) and the grain yield (kgh-1) of rice varieties were extrapolated from the net plots. Statistical analysis software was used to analyze all data generated, where significant means were compared using Duncan Multiple Range Test. The results revealed that RETC output for van Genutchen parameters demonstrated significant difference between the two tillage practices, irrigation schedule and depth on the value of curve fitting parameters (n). Soil physical quality index (S) increased with increase in soil depth, although not statistically different. From the finding, the S-index in the study area was in the range of 0.023-0.025, which by grouping was considered moderately suitable for optimal root growth. Also, FARO 44 performed better than other varieties in both 2018 (540.05 kgh-1) and 2019 (5835.85 kgh-1), respectively with one day irrigation schedule and convectional tillage practice. Forage legume incorporation during rainy season should be encouraged to improve the soil physical quality over time.