Development of Tractor Drawn Potato Digger

The post-harvest loss of potatoes in Ethiopia is more than 25% which includes harvesting loss. In the conventional method, the potato is harvested either manually with a hand hoe or by animal-drawn equipment, which is a tedious, labor-intensive, and time-consuming operation. To overcome these problems, the tractor-drawn potato digger was developed, and evaluated for its performance. The performances were evaluated in terms of harvesting efficiency, exposing efficiency, percentage of tuber damage, effective field capacity, field efficiency, and fuel consumption. The developed digger is tested at three levels of forward speeds (2.5, 3, and 3.5 km/h) and three different rake angles (10, 15, and 20°). The performance of the digger was found to be optimum at rake angles of 20° and forward speed of 2.5 km/hr. The results revealed that maximum harvesting efficiency of 98.21% was obtained with lower potatoes damage of 4.32% whereas the exposing efficiency, undug potatoes, effective field capacity, field efficiency, and fuel consumption were found to be 91.48%, 1.79%, 0.11ha/hr, 84.71%, and 1.17 l/hr, respectively. The analysis of variance revealed that forward speed and rake angle had significant effects on harvesting efficiency, undug potatoes, potato damage, effective field capacity, field efficiency, and fuel consumption at a (P<0.05) level of significance. The costs of harvesting per hectare were 2876 and 6050 ETB/ha for the developed potato digger and traditional potato digging methods, respectively. The cost of operation per hour for tractor-drawn potato diggers and traditional methods was 169.23 and 700 ETB/hr, respectively. The saved cost of harvesting was 52% and the saved in time was 75% compared to traditional potato harvesting. From these performance indicators, it can be concluded that this digger is efficient, effective, and economical, and it is recommended that the technology be promoted for potato producer farmers.