ABSTRACT
In the bid to find solutions to the problems associated with planting on ridges and for the fact that existing planters for cereals in Nigeria are not built on the concept of ridges but on flat land planting, this research work was embarked upon to develop anengine-propelled two-row ridge planter for cereals. The planter was designed, fabricated and evaluated. The planter has the functional units of two hoppers, two seed metering units, two delivery chutes, two coulters, two soil covering devices and a drive mechanism. The developed planter was evaluated in terms of planting speed, seedling emergence, plant-to-plant spacing, energy expended, seed delivery rate, number of seeds per hill and percent seed damage. The results obtained compared with those of an existing IAR single-row animal drawn planter and with the manual planting method in 2012, 2013 and 2014 planting seasons using Quality Protein Maize (QPM) as the test crop. In terms of planting speed, seedling emergence and plant-to-plant spacing, the engine-propelled planter performed best. It recorded the highest average planting speed of 0.55 m/s,average plant density of 28,803 plants per hectare representing 73.85% of the design plant density, plant spacing of 25.9 cm, which is the closest to the designed plant spacing of 25cm. The engine-propelled planter expended the least energy of 261.82 MJ/ha as against the 2,308.18 MJ/ha and 1,099.09 MJ/ha of energy for the animal drawn planter and manual planting respectively. The seed delivery rate was 19.80kg/ha, Effective Field Capacity of 0.22ha/hr, field efficiency of 70.71%, Speed of Emergence of 4.33 plants per day, Mean Emergence Data of 9.6, Emergence Rate Index of 6.77 and a Relative Emergence of 0.87. The performance indices were subjected to optimisation using the Response Surface Methodology with a Central Composite Design (CCD). The Design Expert, Release 9.0 was used as the optimisation software. Models were developed for optimizing each of the performance indices of seedling emergence, plant spacing, depth of planting, number of seeds per hole, energy expended and number of damaged seeds using speed of planting and soil moisture content as the input variables. Mathematical models were developed for optimising the number of emerged seedlings, depth of planting, plant-to-plant spacing, number of seeds per hole, energy expended and the number of damaged seeds (as the performance indices) using the engine-propelled planter only. The Sequential Sum of Squares, Lack of Fit Test and the Summary of Statistics were used in determining that the quadratic models were best in evaluating the optimal values of the performance indices. Results of optimisation showed that the seedling emergence could be maximised to 24.52 plants within the planting area of 0.0011 hectares which translated to 22,290 plants per hectare of maize. The results also revealed that the maximum depth of planting was 36.74 mm, plant-to-plant spacing was maximised to 44.00 mm and maximum number of seeds per hole was determined to be 3 seeds. The energy expended could be minimised to 1.97MJ over 0.0011 hectares (or 1,790 MJ in one hectare) and the number of damaged seeds could be minimised to zero.At the end of the research, it was concluded that the developed 2-row engine-propelled seed planter could be used for planting maize seeds on ridges in well drained sandy loamy soils and that it compared favourably with the existing IAR single row planter and the manual planting. The engine-propelled planter was produced and assembled at a cost of N176,178.08.
