The results of laboratory, field and household tests of a tractor model implemented on sowing and row-spacing processing of cotton-plant during the growing season are specified in the article. Agrotechnical evaluation of damage to plants and knockability of cotton fruit elements by machine-tractor unit, consisting of compared tractors and cultivator, showed that knocking down cotton fruit elements in one pass at tractor with 4K4 wheel arrangement is less by 10% compared to tractor with 3K2 wheel arrangement. The fitability of cultivator on basis of a high-clearance mock tractor with 4K4 wheel arrangement on cotton-plant processing in the fruiting stage according to main indicators complies with the standards established in the Initial requirements.

The results of researches implemented in the sphere of improving the agrotechnical passability of 4-wheeled universal-row cotton crop tractor are specified in the article. Replacing these two types of wheeled tractors with one high-clearance 4-wheeled tractor significantly reduces the range of fleet and increases the annual load of universal-row crop tractor of 1.4 class, and finally, increases the efficiency of their applying. The weight distribution of perspective four-wheeled universal-row crop tractor onto four wheels and fully drive reduces the negative impact on soil in comparison with three-wheeled tractor and allows to aggregate machines having enlargedrow-spacings. Evaluation of P indicator (the passability margin) is shown. It characterizes the passability through more problematic matters due to traction-coupling properties presowing soil processing proceedings, which showed the possibility of applying the tractor as well at all remaining operations, provided for by the technological map and being performed by the units on the base of this tractor.