Improvement of the soybean harvesting process as a way to increase the quality of seeds

The quality of seeds is the most important factor in increasing the yield of agricultural crops, including soybean. However, on the average, up to 20–25% of soybean seeds, sown in the Amur re-gion, are substandard. At the same time, one of the main reasons for the decline in the quality of seed material is significant crushing and damage of soybean during harvesting and processing. Up to 10 different marks of combines, which allow a high degree of crushing of bunker grain, are used in harvesting soybean in the Amur region. The crushing of grain by combines of different marks varies in the range from 6,9 to 15,1 percent. Combines of Russian and foreign production are mainly single-drum by design and collect the threshed soybean grain in one bunker, while they do not separate seeds according to the biological diversity inherent in soybean. As a result, soybean yield losses reach 2,7-3,3 c/ha. In order to reduce grain losses from the crushing and obtaining high-quality seeds, a new device, based on a two-stage threshing combine with double-flow cleaning and with two bunkers, has been developed. The study of the operating modes of the threshing and separating device for threshing, separation and damage of soybean seeds along the length of the combine thresher was carried out in order to select and preserve the part of the biologically valuable and high-quality soybean seeds from the crushing during combine harvesting of soybean with reduced grain moisture (less than 12%). The conducted research with the use of the complete factorial experiment method and processing the results made it possible to create mathematical models of separation and seed damage, on the basis of which a nomogram was built to determine separation and the content of damaged soybean seeds, which are obtained in the zone of the first drum, depending on the techno-logical adjustments of the threshing apparatus, grain feed and grain moisture.