Abstract
Two kinds of simulators (Fig. 1, 2) and two kinds of fields (open-field, artificial-field) were provided for clarifying the effects of soil conditions on the pulling force of root vegetables. Two methods of simulator setting in soil, driving method and burying method, were prepared for soil conditioning.
Effects of the surface area (S) in soil on the pulling force (F) were investigated with the burying method by using simulator type 1 in open-fields. The results of measurements, the relationship between the surface area in soil and the pulling force were expressed by two linear formulas (Fig. 3).
F=0.022S-0.056
F=0.023S-0.116
Relationship between the soil moisture (wet and dry condition) and the pulling force were investigated with the driving method by using simulator type 2 in the small artificial-fields. The results of measurements indicated more pulling force required in the wet soil conditions than those in the dry soil condition (Fig. 4).
The form of simulators did not disturb the linearity between the surface area in soil and the pulling force (Fig. 5, 6, 7).
