The effect of soil deepening on soybean yield by using various sowing machines
The influence of agricultural methods and soil and climatic conditions on soybean cultivation in the southern regions of the Amur Region was researched. Schemes of two-factor experiments to study the effectiveness of deepening the arable layer of soil during crop cultivation in 2014–2016 included the following options. Factor A – tillage: autumn – disk plowing or cultivation; spring disk plowing or cultivation; summer – inter-row cultivation with or without para-plowing. The options were combined in different ways, whereby the option of soil tillage with a disc harrow in autumn and spring was taken as control. Factor B: sowing with seeders SZ-5.4 and SP-3.6 L with row spacing (options – 15, 45 and 60 cm) with various tillage systems. In 2017–2018 experiments were carried out according to the following schemes. Factor A – tillage: in autumn tillage depth at 0.12 m with a disc harrower PM-8; in spring, before sowing – at 0.10 m (cultivator Case Tiger Mate 225 – control); autumn – tillage depth at 0.28 m (cultivator Lemken Karat 9/400); spring, before sowing – at 0.10 m (Case Tiger Mate 225). Factor B – seeding units included Amazon DMC 9000 (control); Amazon DMC 1200, Case Pro Disk 500 AFS, John Deer 1890, Lemken Solitair 12, Horsch Pronto 9 DC, Tom’ 12, SP-3.6 L. Deep autumn cultivation, in contrast with disk plowing, ensures a more favorable waterair regime for plants and an increase in soybean yield. Seeding units Case Pro Disk 500 AFS, John Deer 1890, Amazon DMC 9000 and SP-3.6 L used in combination with Lemken Karat 9/400 + Case Tiger Mate 255 machines for deepening the arable layer provided an increase in soybean yield by 25.0–38.3% compared to soil tillage with discs. It is recommended to use wide-span seeding units for soybean cultivation in large and medium-sized farms in fields with subdued relief in accordance with high-intensity technology. It is advisable to use SP-3.6 L seeder with a seed shoe for organic crop production in small-scale agricultural enterprises.