Performance Evaluation of a Tractor Drawn Groundnut Digger/shaker for Agricultural Productivity

Transcription

1 Performance Evaluation of a Tractor Drawn Groundnut Digger/shaker for Agricultural Productivity Abstract Ademiluyi, Y.S., O.A. Oyelade, D. James and I.C. Ozumba National Centre for Agricultural Mechanization (NCAM), Ilorin Field test was conducted to evaluate the performance of NCAM developed tractor drawn groundnut digger/shaker. A 65 hp styer tractor was used for drawing this implement. The parameters evaluated were, soil moisture content, effective field capacity, theoretical field capacity, field efficiency, digging efficiency, percentages of damaged pods, exposed pods loss, unexposed pods loss, undug pods loss and total of pods loss. The experimental plots were laid side by side in a randomized complete block design (RCBD). Results of the main field test indicate that using the tractor drawn groundnut digger only performed better than using the tractor drawn groundnut digger/shaker combination with highest average digging efficiency of 43.74% at a soil moisture content of 5.60% (db), field efficiency of 85.93% and effective field capacity of 0.65 ha/hr both at soil moisture content of 4.63% (db). While the tractor drawn groundnut digger/shaker combination recorded the highest average digging efficiency of 39.73% at a soil moisture content of 3.02% (db), field efficiency of 60.16% and effective field capacity of 0.41 ha/hr both at soil moisture content of 3.02% (db). Results obtained from this study also showed that digging efficiency and percentage of total are inversely related to one another signifying that at lower digging efficiency there would be high percentage of total pod loss and vice versa. Keywords: Evaluation, Tractor, Groundnut, Digger, Shaker, Performance 1. Introduction Nigeria has been one of the largest producers of groundnuts in the world. Even as far back as 1930 the total groundnut acreage was recorded as 421,052 hectares with a production of 316,684 tons. Nigeria has also been a leading exporter of the crop with generally 60% to 70 production being exported (Kaul, 1978). Groundnut is an available oil crop in the world because of its numerous uses as food. Some developing countries such as Gambia, Senegal, Niger, Mali and Sudan depend on groundnut to provide the bulk of their foreign exchange (Ademiluyi, 1997). Harvesting of groundnut is one of the areas of groundnut production that need to be addressed due to the drudgery involved when leaves start yellowing and begins to fall down. This shows that the crop is ready for harvesting. At this stage, the pods become reticulate, the seed is separated from the shell of the pod. The plant could be either pulled and dug out and left on the field for two or three days for sun drying (Ademiluyi, 1997). In the traditional method of groundnut harvesting, the vines are uprooted with hand or hand tool with the entire root system. Groundnut plant belongs to the leguminous family 115

2 and it is a tap rooted crop. The pods are located up to a depth of 7 10 cm usually referred to as pod zone. It takes from man-hr to harvest a hectare. The cost of operation per hectare for a plot done by the tractor drawn digger is much lower than a plot done through digging by manual method. The cost of using a tractor drawn digger is N700 while the cost of manual digging is N2, (Ademiluyi et al., 2004). The manual harvesting can cause depletion of soil fertility due to removal of the complete root system along with nitrogenous nodules, however, this can be eliminated using mechanical harvester. The mechanical harvesting of groundnut has advantage of reducing the cost and labour requirement and is conducive to better soil fertility as the blade of the digging implement cuts through the root below the pod zone and leaves the remaining root system in the soil itself. Harvesting by mechanical means, however, requires that the fields should have sufficient moisture to enable the blade to penetrate to the desired depth. It also requires that groundnut should not be over mature before harvested. The soil attached to the vines is loosen in the process and groundnut plant is easily picked up and put at the furrow to get exposed to the sun for speedy drying (curing). The use of machines is one of the inputs which, apart from giving relief from drudgery, influences the efficacy of the other inputs either directly or indirectly. Timely and correct placement of seeds, optimal harvesting procedures and timing, adequate shelling and related items are examples where machines could influence the production efficiency. Cost of production would also be influenced by the degree of usage of machines (Kaul, 1978). The major reasons for the demand for groundnut machinery are to reduce drudgery, to improve timeliness, and to increase productivity and income. The most desirable machines indicated by farmers are stripper, digger, and planter for irrigated area; planter, stripper, and weeder for rainfed area; and stripper, weeder, and seed shelter for area using residual soil moisture (Chinsuwan et al., 1991). Harvesting operation of groundnut with the use of small hoes for digging ridges is labour intensive. Not only in manual digging are many groundnut pods unharvested, but the harvesting cannot be completed on schedule. In a way to boost groundnut production in Nigeria, NCAM developed tractor drawn groundnut digger/shaker was evaluated in order to access the implement performance in alleviating drudgery associated with the traditional method of harvesting groundnut. Therefore, this paper presents the performance evaluation of NCAM developed tractor drawn groundnut digger/shaker. 2. Materials and Methods The study was carried out at the National Centre for Agricultural Mechanization (NCAM), Ilorin. This fieldwork was carried out in November 2002 on the large cultivation plots of the experimental farm which offered the tractor drawn groundnut digger/shaker an exposure to wide range of soil condition for farming situations in the locality. The groundnut crop used for the study was planted on 20 th June, A 65 hp styer tractor was used for drawing the groundnut digger/shaker implement. A total area of 0.80 hectares of sandy loam soil was used for the main study. The field was divided into three different experimental plots with each plot having a dimension of 25 m by 100 m. 116

3 Each of this plot was further sub-divided into two plots to allow for different operation of tractor drawn groundnut digger and digger/shaker combination. Trials were carried out on each of the plots at three days interval. This was done to assess the performance of the machine at various soil moisture contents. The remaining 5 m x 100 m left out of the field was sub-divided into two parts to serve as a demarcation between the shared plots. The soil moisture content was determined using the oven dried method. The speed of operation for the tractor was determined by taken the average time it took the tractor to cover the longest distance. The time factors (such as actual time, obstruction time and turning time) which were used for determining the total time for completing each tillage operation was measured with a stop watch. A 1m 2 steel bar was used as marked area for taking samples of harvested groundnut plant, unharvested groundnut plant, damaged groundnut pods, exposed groundnut pods, detached groundnut pods lying exposed, detached groundnut pods inside the soil that fell within the 1m 2 marked area on each selected pot. The samples from these selected pots were used to access the performance of the tractor drawn groundnut digger and digger/shaker combination. 2.1 Working principle of the implement The digger consists of a single-place blade mounted on a frame with the help of two shanks/standards (Fig. 1). The shaker consists of two wheels supported by a main frame which has finger-like handles placed at distances equivalent to the planting intervals (Fig. 2). The cutting edge of the blade is adjusted to operate at a depth slightly below the pod zones. As the tractor moves forward, the blades cut the roots of the groundnut vines and loosen the soil. The shaker is then employed to pull out the vines from the loosened ground and shake off the soil adhered to the roots and pods. The plant can be left exposed on the ridges for 3-4 days for sun drying before collection for stripping and threshing. 2.2 Test parameters Five samples were taken from each of the sub-plot, where parameters such as percentage exposed, buried, damaged, etc., were used for the computation of the machine losses and digging efficiency. This was done in accordance with the Indian Standards Test Codes for groundnut harvester, Animal drawn (IS: ). The following formula was used in the computations: i) A B C (1) C ii) damaged pods = A x 100 (2) G iii) exposed pods loss = A x 100 (3) H iv) unexposed pods loss = A x 100 (4) v) undug pods loss = K A x 100 (5) where, A = total quantity of pods collected from the plant in the sampled area. 117

4 B = quantity of clean pods collected from the plant dug in the sampled area, exposed pods lying on the surface and the buried pods. C = quantity of damaged pods collected from the plants in the sampled area. G = quantity of detached pods lying exposed on the surface. H = quantity of detached pods remained inside the soil in the sampled area. K= quantity of pods remaining undetached from the undug plants in the sampled area. vi) Digging efficiency = where, 100 total podloss (6) total pods loss = exposed pods loss + loss + undug pods loss Effective field capacity vii) Field efficiency = x 100 Theoretical field capacity unexposed pods (7) where, theoretical field capacity is the rate of field coverage that would be obtained if the digger was operating continuously without interruption e.g. unclogging the blade, and turning time; effective field capacity is the actual average rate of coverage, which includes the lost time in turning at row end, adjustment-making, etc. 3. Results and Discussion Results of the harvesting operation carried out on the groundnut crop at 149 days after planting, 152 days after planting and 155 days after planting using the tractor drawn digger and digger/shaker trials at different soil moisture content conditions are presented in Tables 1 and 2, respectively. Table 3 presents the time taken to pack the harvested plants using two labourers. It can be deduced from Tables 1 and 2, that the soil moisture content was generally too low. As a result of this, it was discovered that as the soil dries up the implement finds it hard to penetrate into the soil thereby resulting to a very low digging efficiency of the implement during operation. The weeds were found to interfere with the digging exercise by increasing soil resistance. The edge of the crop was found to affect the number of pods left in the soil. The average cone penetration at the pod zone is N/cm

5 From Table 1, it can be deduced that the highest average digging efficiency recorded for the tractor drawn digger was 43.74% at soil moisture content of 5.60% (db) while the lowest average digging efficiency of 27.50% recorded for the tractor drawn groundnut digger occurred at a soil moisture content of 4.63% (db). This decrease in digging efficiency was mainly due to the hardness and caking of the soil, which makes it more difficult for the digger to penetrate and for the pods to get easily loose from the soil (most of the groundnut pods get hooked within the soil). This implies that the soil moisture content has direct influence on the digging efficiency of the implement. The highest average effective field capacity obtained using tractor drawn groundnut digger was 0.65 ha/hr. The highest field efficiency of 85.93% recorded for tractor drawn groundnut digger occurred at a soil moisture content of 4.63% (db). From Table 2, the highest digging efficiency recorded for tractor drawn groundnut digger/shaker combination was 39.73% occurred at soil moisture content of 3.02% (db) while the lowest average digging efficiency of 32.56% recorded for the tractor drawn groundnut digger/shaker combination occurred at a soil moisture content of 5.60% (db). The highest average effective field capacity obtained using tractor drawn groundnut digger/shaker combination was 0.41 ha/hr. The highest field efficiency of 60.16% recorded for tractor drawn groundnut digger/shaker combination occurred at a soil moisture content of 3.02% (db). The low values obtained for both average effective field capacity and field efficiency of the tractor drawn groundnut digger/shaker combination (0.41 ha/hr and 60.16%) when compared to the high values obtained for the tractor drawn groundnut digger (0.65 ha/hr and 85.93%) was as a result of the time spent for crop recovery. In Table 3, it can be deduced that the time taken for two labourers to pack harvested groundnut plants from a single row of a plot done by the tractor drawn groundnut digger, takes much time when compared to the plot done by the tractor drawn groundnut digger shaker combination. This was as a result of the effect of incorporating the shaker to the digger which makes packing of the groundnut plants much easier for the labourers. What the shaker component of the implement does, is to uproot or pull up the groundnut plant from the soil through its finger like projection as the implement is been drawn forward by the tractor. 4. Conclusion The results obtained from the evaluation of the implements led to the following conclusions: 1. As timeliness of operation is very vital in agricultural practices, this also applies to the case of groundnut production. When groundnut crops are not harvested during their right time of harvest, harvesting of groundnut plants using the digger/shaker will produce a very low value of digging efficiency. 2. Soil moisture content is a major factor influencing the digging efficiency of the implement. Soil moisture content between 12% to 15% will be preferable to work with while carrying out harvesting operation on a groundnut farm. 119

6 3. The incorporation of the shaker to the digger makes packing of the groundnut crop much faster than using the digger only. This was as a result of a lesser work done in uprooting the crop from the soil because most crops have already been uprooted by the shaker coupled to the digger. 4. Digging efficiency and total percentage of are inversely related to one another signifying that at lower digging efficiency there would be high percentage of total and vice versa. References Ademiluyi, Y. S Performance Test for improvement of IAR groundnut Sheller/Decorticator. Unpublished M.Sc thesis submitted to Agricultural Engineering Department, University of Ibadan. Pg Ademilyi, Y.S., James, D., Ozumba, I. C. and Olowonibi, M. M Performance evaluation of a Tractor Drawn Groundnut Digger/Shaker. Published in NCAM Research Publication. Pg Chinsuwan, W., Wongpichet, S., Sudajan, S., Chakkapak, C., Krishsanaserani, S., Mongkolthanatas, J., and Thongsawatwong, P Final Report Groundnut Mechanization Project: A Report Submitted to the International Development Research Centre (IDRC, Canada). IDRC File No. 3-P Kaul, R.N An Overview of the Mechanization Position Groundnut Production in Nigeria: In Proceedings of the National Seminar on Groundnut Production. Pg

7 Table 1. Efficiency of the Implement (Digger) DAP Average moisture content exposed unexposed undug total loss damaged pod Total % of pod loss Digging efficiency Field efficiency Theoretical field capacity (ha/hr) Effective field capacity (ha/hr) Table 2. Efficiency of the Implement (Digger/Shaker combination) DAP S/No Average moisture content exposed unexposed undug total loss damaged pod Total % of pod loss Digging efficiency Field efficiency Theoretical field capacity (ha/hr) Effective field capacity (ha/hr) DAP = Days After Planting 121

8 Table 3. Packing time for one row using two labourers S/No. DAP D D/S mins:3secs. 6mins:29secs mins:13secs. 3mins:55secs mins:46secs. 3mins:25secs. where, D = Digger D/S = Digger/shaker DAP = Days after planting Fig. 1: Pictorial view of the groundnut digger Fig. 2: Pictorial view of the groundnut digger/shaker 122