Effect of λ-Ratio on Work Efficiency of Rotary Offset Tiller in Litchi Orchard

Rotary tillage implements are now projected as important machinery for better seedbed preparation. However, ordinary rotavator being in line with the tractor center line at the rear cannot be used efficiently in orchards due to the hindrance posed by narrow space between the plants. Therefore, the concept of a rotary offset tiller was proposed, which could perform intercultural operation between the plants. The study was conducted to evaluate the work efficiency of rotary offset tiller at Horticulture Research Center, Pantnagar in litchi orchard. It was found that the thrust developed in case of L-shaped blades increased (918.9 to 1449.4 N) as the forward speed increased (2.0 to 3.0 km/h) with increase in depth of cut (80 to 120mm) for the shield kept in the lowered (down) position. The fuel consumption was higher 8.84 l/h at given forward speed 3.0 km/h with 120 mm depth of cut. Soil break up (mean mass diameter) resulting from the Impact action of L-shaped blades on soil was observed to increase (1.04 to 2.07 mm) with the increase in forward speed (2.0 to 3.0 km/h). The extent of residue incorporation was the maximum 97.46% at forward speed of 2.0 km/h with 120 mm depth of cut, whereas, at higher forward speed 3.0 km/h, field performance index was observed to be 86.45%. The plant injury at 3.0 km/h was observed to be 66.6%.