Experimental Studies of a Combined Aggregate for Application of Mineral Fertilisers and Sowing

The article presents the results of field experimental studies of sowing grain crops and application of mineral fertilisers by means of a combined two-machine fertiliser application and sowing aggregate on the basis of two grain seeders. A regression equation is obtained, and influence of the velocity of movement, the depth of sowing seeds and application fertilisers into the soil upon the uniformity of seed and fertiliser distribution along the row are determined. On the basis of the obtained experimental data rational parameters of sowing are justified at which the necessary quality of the execution of the technological process will be achieved. INTRODUCTION As one of the basic ways how to increase the efficiency of crop production may be regarded elaboration of the ways for raising the efficiency of aggregates and decreasing the costs for the execution of technological operations. An analysis shows that the most perspective way for essential decreasing the costs when growing grain crops is the use of combined sowing aggregates which simultaneously perform several technological operations of sowing (Kabakov, 1984; Behov and Djachenko, 2000; Vilde et al., 2006; Chorna, 2012). There are several variants of combined machines for application of fertilisers and sowing. The present article considers a possibility to use a combined sowing aggregate for the application of mineral fertilisers and sowing on the basis of two grain seeders. The seeders are trailed by tractor of the traction class 14 kN, which is the most widespread among the agricultural producers in many countries of Eastern Europe. The main advantage of this fertilising and sowing aggregate is to introduce the basic dose of mineral fertilisers into deeper layers of the soil, directly into the area of the future root system of the crop. Justification of the scheme, design parameters and operating modes of the sowing aggregate created by using tractors of the traction class 1.4 on the basis of two trailed grain seeders is outlined in works (Masalabov, 2016; Petuhov, 2016). However, considering the difference between the proposed aggregate and those treated in the works mentioned, a necessity arises to conduct experimental studies about the influence of the sowing parameters upon the execution quality of the process and justification of their rational values. The aim of this study is experimental determination of the influence of the working velocity of the combined sowing aggregate, the depth of sowing seeds and application fertilisers into the soil upon the uniformity of seed distribution, as well as determination of rational parameters. MATERIALS AND METHODS The experimental equipment (Fig. 1) consists of two seeders connected together by a special hitch which allows ensuring the necessary manoeuvrability of the aggregate during its operation. During the execution of the process the first seeder of the sowing aggregate ensures introduction of the necessary basic dose of mineral fertilisers into the