EFFECT OF TILLAGE ON SELECTED SOIL PHYSICAL PROPERTIES AND YIELD OF RICE IN SOKOTO RIMA RIVER FLOOD PLAIN, NORTHERN NIGERIA

Abstract

ABSTRACT A study was carried out on a farmers’ crop field around Kwalkwalawa village in Usmanu Danfodiyo University, to assess the tillage effect on selected soil physical properties and yield of rice at the Sokoto-rima flood plain in Sokoto, Nigeria. The experiment consisted of two tillage treatments i.e. reduced tillage (RT) and Conventional tillage (CT) replicated three times and rice variety, FARO 44 was used as a test crop. Before the onset of the experiment, soil samples were collected by simple random sampling method at 0-10 cm and 10-20 cm depth using auger and core sampler from the experimental plot. A composite sample was prepared for laboratory determination of some soil physical and chemical properties using standard procedures. Measurements of physical (Bulk density, total porosity, temperature) and hydraulic (saturated hydraulic conductivity, water holding capacity and gravimetric moisture content) properties were made on undisturbed core samples at surface (0-15 cm) and sub-surface (15-30 cm) soil depths. Data obtained was subjected to paired t-test using SPSS version 2.0 software package and standard error of mean was used to compare the treatment mean at 5% level of significant. It was found that the soil was mainly clay loam across the two depths and the bulk density of the soils increased with increase in depths from 1.39 gcm-3 at 0-10 cm to 1.42 gcm-3 at 10- 20 cm respectively, while the soil pH measured in both water and CaCl2 slightly increased with depth, indicating neural acidity at both depths. The value of organic carbon, total nitrogen, available phosphorus and exchangeable bases were all very low across the two depths. There was no significant difference in the mean value of bulk density at the depth of 0-10cm, but a significant (P≤0.05) difference was observed between the two values of the bulk density at 10-20cm, with RT having higher values compared to CT. Similarly, the value of saturated hydraulic conductivity (Ksat) was only significant (P≤0.05) between the mean values of Ksat at 10-20cm soil depth, with CT having higher values compared to RT. The volumetric soil moisture content was significant (P≤0.05) only at 0-10cm soil depth, with RT having higher mean values compared to CT. There was also significant difference between the total dry matter, 1000-grain weight and yield per hectare for the two tillage operations, with CT having higher values compared to the RT. Therefore, it can be concluded from the study that FARO 44 performed better in conventional tillage treatment more than the reduced tillage treatment in dry season at Sokoto-Rima flood plainABSTRACT A study was carried out on a farmers’ crop field around Kwalkwalawa village in Usmanu Danfodiyo University, to assess the tillage effect on selected soil physical properties and yield of rice at the Sokoto-rima flood plain in Sokoto, Nigeria. The experiment consisted of two tillage treatments i.e. reduced tillage (RT) and Conventional tillage (CT) replicated three times and rice variety, FARO 44 was used as a test crop. Before the onset of the experiment, soil samples were collected by simple random sampling method at 0-10 cm and 10-20 cm depth using auger and core sampler from the experimental plot. A composite sample was prepared for laboratory determination of some soil physical and chemical properties using standard procedures. Measurements of physical (Bulk density, total porosity, temperature) and hydraulic (saturated hydraulic conductivity, water holding capacity and gravimetric moisture content) properties were made on undisturbed core samples at surface (0-15 cm) and sub-surface (15-30 cm) soil depths. Data obtained was subjected to paired t-test using SPSS version 2.0 software package and standard error of mean was used to compare the treatment mean at 5% level of significant. It was found that the soil was mainly clay loam across the two depths and the bulk density of the soils increased with increase in depths from 1.39 gcm-3 at 0-10 cm to 1.42 gcm-3 at 10- 20 cm respectively, while the soil pH measured in both water and CaCl2 slightly increased with depth, indicating neural acidity at both depths. The value of organic carbon, total nitrogen, available phosphorus and exchangeable bases were all very low across the two depths. There was no significant difference in the mean value of bulk density at the depth of 0-10cm, but a significant (P≤0.05) difference was observed between the two values of the bulk density at 10-20cm, with RT having higher values compared to CT. Similarly, the value of saturated hydraulic conductivity (Ksat) was only significant (P≤0.05) between the mean values of Ksat at 10-20cm soil depth, with CT having higher values compared to RT. The volumetric soil moisture content was significant (P≤0.05) only at 0-10cm soil depth, with RT having higher mean values compared to CT. There was also significant difference between the total dry matter, 1000-grain weight and yield per hectare for the two tillage operations, with CT having higher values compared to the RT. Therefore, it can be concluded from the study that FARO 44 performed better in conventional tillage treatment more than the reduced tillage treatment in dry season at Sokoto-Rima flood plain