Influence of the harvesting method on the processes of moisture accumulation and yield capacity

BACKGROUND: A feature of the climate of the steppe zones of Western Siberia is the frequent recurrence of droughts. Accumulation and preservation of solid precipitation in the form of snow on field in winter is a relevant task, since this directly affects the accumulation of productive moisture in soil by the time of sowing and, as a result, the formation of the future harvest.

AIMS: To determine the influence of the snow cover level, moisture reserves and productive moisture in the soil on a stubble background, harvested with a thresher for direct combining and a rippler on the yield capacity of spring wheat.

METHODS: The field experiment was carried out in 2021-2022 in the steppe zone of the Omsk region at the Novouralskoye Scientific and Production Enterprise of the Omsk Agrarian Scientific Center. In the autumn of 2021, sections of the field were marked out for measurements: wheat stubble field after the thresher for direct combining, wheat stubble field after the rippler. In March 2022, indicators of the height of the snow cover and moisture reserves in the snow were determined on the marked areas using the VS-43 balance snow gauge. In the spring, wheat was sown with the machine-tractor unit, consisting of the RSM 2400 tractor and the Amazone Condor 15001-C sowing facility. In autumn, the chosen field sections were harvested with the Sampo-250 seed-production harvester.

RESULTS: It was found that after harvesting with the thresher for direct combining with a stubble background of about 15 cm, there is a decrease in the moisture reserve in the one-meter-depth layer by almost 2 times, down to 48.6 mm, by the spring period. The moisture reserve on a high stubble background, after the operation of the rippler, on the contrary, was able to persist, as there were 96.6 mm of productive moisture in the one-meter-depth layer by the time of sowing. The average grain yield on the field section sown after the rippler was 1.16 t/ha. The average grain yield on the field section sown after harvesting with the thresher for direct combining was 1.06 t/ha. Thus, the grain increase was 0.1 t/ha or 9.4%.

CONCLUSIONS: The carried out field experiment indicates that, when harvesting with a rippler, there is a twofold increase in productive moisture by the time of sowing, while the increase in the yield of spring soft wheat grain was 9.4%.