The dissertation is about the research of influence of sowing rates, bacterial preparations and microfertilizers on productivity of grades and hybrids of sweet sorghum in the conditions of the Southern Steppe of Ukraine.
For the first time for the Southern Steppe of Ukraine the growth and development of sweet sorghum plants under the influence of the studied factors were studied. The influence of elements of sweet sorghum cultivation technology on the content of total sugars in stems is determined. The best variant of the varieties and hybrids taken for study for maximum productivity of green mass is established. The influence of foliar fertilization with microfertilizers and biological products on quantitative and qualitative indicators of sweet sorghum yield was determined. The optimal seeding rate is substantiated.
The existing technology of sweet sorghum cultivation for the conditions of the Southern Steppe of Ukraine has been improved by selection of varietal-hybrid composition, optimization of sowing rates and the optimal variant of foliar feeding of plants during the growing season is substantiated.
The issue of managing growth processes of formation of high quantitative and qualitative indicators of sweet sorghum yield depending on the studied elements of cultivation technology has been further developed.
The author studied the peculiarities of growth and development of sweet sorghum plants depending on the varietal-hybrid composition, seeding rates, biological products and micronutrients. The dynamics of accumulation of raw mass and content of dry matter in the studied varieties and hybrids, as well as the formation of the assimilation surface area, net productivity of photosynthesis and photosynthetic potential depending on the studied factors are established. The optimal structure of elements of sweet sorghum harvest depending on the studied factors is determined. The yield of green mass of sweet sorghum and the content of total sugars in the stems were determined depending on the studied factors. The economic and energy efficiency of the studied variants of sweet sorghum cultivation technologies are calculated.
As a result of analyzes and calculations, it was found that the optimal indicators of field germination of seeds, plant survival, stocking density, plant height, quantitative and qualitative indicators of yield provides sowing hybrid Medoviy with a seeding rate of 130 thousand grain pieces per hectare and foliar fertilization in combination with microfertilizer «Quantum» and biological product Biocomplex-BTU plants in the phase of tillering and tubing.
According to the results of research, it was determined and recommended for the production of sowing of sweet sorghum by the hybrid Medoviy with a seeding rate of 130 thousand grain pieces per hectare under the conditions of fertilizing plants in the phase of tillering and tubing with a complex of microfertilizers «Quantum-Bor Active» (0,3 l/ha), «Quantum-AquaSil»(1 l/ha), «Quantum-Chelate Zinc» (1 l/ha), «Quantum-Amino Max» (0.5 l/ha) in combination with the biological product «Biocomplex-BTU» (2 l/ha), which provides the highest yield of green mass 72-83 t/ha. In years with drier weather conditions for the sowing period to obtain higher yields of green mass of sweet sorghum, sowing rates should be reduced to 100 thousand similar seeds per 1 ha. This will ensure high profitability at a low unit cost of production.
Key words: sweet sorghum, seeding rates, biological preparations, microfertilizers, productivity, sugar content, economic efficiency, bioenergy evaluation
