Productivity of sorghum crops depending on agrotechnical methods of cultivation in the regions of the Russian Federation (review)
The review considers the unique diversity and versatility of the use of sorghum crops. The dependence of the yield of biomass and grain of varieties and hybrids of sorghum crops on the applied elements of the crop cultivation technology is analyzed: width of row spacing, density of standing plants in different zones of sorghum sowing in the Russian Federation. A variety of soil and climatic conditions of sorghum cultivation regions differ in the temperature regime, the reserves of soil moisture before sowing, the level of soil fertility, which determines the need to select the optimal elements of technology that ensure the achievement of the highest yield of varieties per unit area with the lowest material and technological costs. The analysis of the ways of placing plants on the own area also indicates the significant role of varietal biological features in increasing the sorghum yield, the purpose of sowing, and the level of field contamination. With limited resources of productive moisture for high-yielding sorghum varieties with a powerful habitus, wide-row sowing with row spacing of 70 cm and the density of standing plants 80-350 thousand per 1 ha, depending on the variety. Low-growing early-maturing thin-stemmed forms of grain sorghum should be sown in the usual ordinary row way with a row spacing of 15 or 30 cm with plant density of 500-600 thousand/ha. Sudan grass varieties that can withstand high density of standing plants (depending on agroclimatic conditions – up to 1.0-3.0 million per 1 ha) are cultivated using the technology of spiked cereals. As the result of the literature data analysis, the following trend has been revealed: the drier the growing conditions, the greater the requirements for choosing the optimal parameters of agrotechnical methods of cultivating sorghum crops aimed at the reducing the number of plants per area unit considering the specific character of the region of sorghum sowing.