Theoretical and experimental substantiation of the application of an autonomous self-propelled row seeder in technologies for establishing field experiments and breeding trials

Abstract

The mechanization of plot sowing remains one of the bottlenecks of the breeding and seed-production process: serial breeding seeders are still aggregated with class-1.4 tractors, which forms an excessive wheel track and introduces a systematic error into the experimental data through compaction of the soil horizon. In parallel, global precision-farming practice demonstrates a steady trend toward the adoption of lightweight autonomous platforms equipped with RTK-GNSS navigation with a positioning accuracy of up to ±8 mm; however, the adaptation of such solutions to the tasks of establishing field experiments and competitive variety testing has hardly been considered. The aim of this study was to theoretically substantiate and experimentally confirm the feasibility of replacing tractor-mounted aggregation with an autonomous self-propelled row seeder when establishing field-experiment plots and breeding nurseries. The methodology included a structural and functional analysis of a prototype self-propelled electric platform with a mass of 480 kg and a four-row sowing unit, laboratory bench tests of the sowing uniformity of wheat and barley seeds at various speed modes (0.8–2.5 km/h), as well as field experiments on 10 m² plots with recording of the seeding depth, inter-row deviation and soil density along the running-gear track. The coefficient of variation of sowing uniformity was 11.3–16.8 % depending on the crop and speed, which falls within the agrotechnical standards for plot sowing. The contact pressure of the autonomous platform on the soil did not exceed 28 kPa — three times lower than the threshold value for loamy soils. The obtained results indicate the possibility of integrating autonomous self-propelled seeders into field-experiment establishment technologies without loss of sowing accuracy and with a substantial reduction of the anthropogenic impact on the experimental plot.