Development of an Integrated Tool for Small-scale Maize Farming in Uganda

About 62% of the maize produced in developing countries is cultivated manually owing to limited access to appropriate technology. Available technologies perform a single operation, necessitating farmers to buy multiple implements, which is expensive. In this study, an ox-drawn tool integrating a plough, planter and cultivator for small-scale maize farming was developed and its performance evaluated. Planting and cultivating units were designed and fabricated for assembly onto an existing standard ox-plough beam. The integrated tool was tested in the field to assess the effectiveness and efficiency of cultivation and planting of maize. Results showed that the planting unit had an average seed rate of 35.4 kg ha-1 with a seed damage of 4% and an effective field capacity of 0.15 ha h-1 at a field efficiency of 87.3%. The cultivating unit had an effective field capacity of 0.1 ha h-1 and a weeding efficiency of 86%. The efficiency, effectiveness and reliability for field operations are superior to manual operations currently used by farmers and are comparable to single-unit prototypes developed in other countries. This demonstrates the technical feasibility of integrating planting and cultivation units onto an existing mouldboard plough instead of buying multiple tools.

Tillage systems and nitrogen timings effect on growth, stay green and grain quality in maize (Zea mays L.)

Nitrogen (N), being mobile in soil is exposed to various losses owing to unwise use of nitrogen fertilizer, and conventional soil and crop management practices which can be minimized by temporal nitrogen application and different tillage practices. This study was conducted to elucidate the effect of different tillage systems and nitrogen timings on growth, stay green and grain quality in maize. Three tillage systems viz. T1: tillage with cultivator, T2: mouldboard plough + 2-cultivations, T3: chisel plough + 2-cultivations; and five nitrogen timings viz. N1: whole at sowing, N2: ½ at sowing+½ at V5 (5-leaf stage), N3: ½ at sowing+½ at tasseling, N4: ½ at V5+½ at tasseling, N5: 1/3 at sowing+1/3 at V5+1/3 at tasseling). Tillage systems and nitrogen application had significant effect on leaf area per plant, specific leaf area and leaf area ratio. Tillage systems had non-significant effect on stay green and grain quality parameters except for oil contents. However, nitrogen timings had significant effect on chlorophyll a, b and total contents as well as grain quality parameters. The higher a, b and total chlorophyll contents were noted with three splits i.e. 1/3 at sowing+1/3 at V5+1/3 at tasseling compared with other treatments. The results suggest to grow maize by preparing the field through chisel plough and applying N in three splits to improve its growth, chlorophyll contents and grain quality.

Phosphorus forms and their distribution under long-term no tillage systems

Phosphorus (P) stratification in no-tillage (NT) systems has important implications for crop growth and potential P loss, but little is known about P forms and their distribution when mineral P fertilizers are placed to the depth of 5 cm in NT soil. A 10-year field experiment was used to study the effect of NT and mouldboard plough (MP) on soil P forms at three depths (0–5, 5–10 and 10–20 cm) and their relationship with Fe and Al oxides. The results indicated that stratification of organic P forms occurred under NT treatment, and Fe oxides may have a stronger capacity for adsorbing the P forms. When mineral P fertilizers were placed to the depth of 5 cm under NT treatment, there was no significant difference in P forms or crop yield between NT and MP treatment, and orthophosphate did not show any significant difference under NT treatment between 0–5 cm and 5–10 cm depth. Overall, the agricultural management practice that mineral P fertilizers are placed to the depth of 5 cm under NT treatment could result in stratification of P forms, while the changes in the distribution of P forms in soil profiles might help reduce potential P loss in surface runoff and do not make any difference to crop growth.

Plough section control for optimised uniformity in primary tillage

Primary tillage is in many cases crucial for successful crop establishment and weed and pest control. Inversion tillage using a mouldboard plough may be required when a uniform ploughing operation covering the entire field is preferred. The ploughing operation is especially challenging at the interface area between headlands and the main cropping area. Overlapping at the interface causes a mixing of the topsoil, rather than a soil inversion, and poor burial of residues and weeds, especially of concern in organic farming. The aim of the research was to study novel plough section control designs to optimise the interface area. Concept designs with hydraulic control were studied and the preferred was developed and tested in real field operations. The research concluded that the concept was functional and by visual inspection the interface was optimised. In addition, the section control can improve operations in irregularly shaped fields.