DESIGN, DEVELOPMENT AND FIELD TESTING OF A MULTIPURPOSE POTATO DIGGER

A tractor mounted, two row multipurpose potato digger (MPD) was developed and tested. Major components of the prototype were three point hitch system, main frame, two flat columns joining frame and blade. Blade was fitted with two detachable ridge opening devices. On the sides of the columns, two furrow guides were provided for stability of the digger. Two replaceable, high carbon steel shovels were fitted in front of blade for easy penetration in dry field conditions and to prevent it from wear. Prototype was successful in digging both early (60-65 days, without removing haulms), and main crop at optimum moisture conditions and also in dry conditions at row-to-row spacing of 610 as well as 686 mm. In digging early crop, labour requirement was reduced by 37% compared with complete manual harvesting with khurpa and damage reduced by 72%. In main crop, MPD was compared with digger elevator (ED). Exposure of potatoes by the MPD was directly proportional to forward speed. Under optimum moisture conditions, MPD exposed 3.5% less tubers than ED and field capacity was 0.36 ha/ h more than ED. In dry field conditions exposure was higher by 15.9% in case of MPD. This prototype was also effective in harvesting potatoes planted at 686 mm (27 inches) row to row spacing. This required slight adjustment of ridge opening devices of the blade. There was no significant breakdown of MPD in a long-term evaluation.