Field Performance of Weeding Blades of a Manually Operated Push-Pull Weeder

The field performances of five different configurations of weeding blades of a push-pull weeder were evaluated. A performance index was developed to compare the blades. The field tests were conducted in greengram ( Phaseolus aureus) crop infested with grassy weeds such as Echinochloa crusgalli and Cyperus rotundus on lateritic sandy loam soil. The results indicated that the overall performance of a straight flat blade was the best; the field efficiency was highest, physical damage to crops was the least and weed removal per unit area was the greatest. In field weeding with this weeder the largest part of the human energy consumed per cycle of push-pull operation was spent in cutting soil and weed roots and a smaller part was used in penetration of the blade into the soil. The average power requirement in the operation was 21·3 W, a work rate which could be sustained by an average farm worker. Weeding with this weeder increased the work output of the worker by approximately four times compared with manual weeding.