BIOENERGETICS FORMATION OF SUGAR SORGHUM VARIETIES DURING DIFFERENT SOWING AND HARVESTING PERIODS

Abstract

The article presents the research results on bioenergy parameters formation (green mass yield, biogas output, solid fuel, energy evaluation of fuel) of sugar sorghum varieties at different sowing and harvesting times. When harvesting sugar sorghum in the third decade of August, on average over two years of research, the highest total yield was observed in Dovista variety during the second sowing period and amounted to 65.9 t/ha, 56.2 t of which is stem yield and 2.2 t – panicle yield. A slightly lower yield was noted in the same variety during the first sowing period – 63.7 t/ha, where stem weight was 54.0 t and 2.9 t – panicle weight. In Prysyvashskyi 85 variety, for the same harvesting period and for sowing in the third decade of April, the total yield was 53.3 t/ha, which is 2.2 t more compared to the sowing period in the first decade of May. During the second harvesting period, the total yield of Dovista variety when sown in the first decade of May was 69.6 t/ha (which is the highest indicator for all sowing and harvesting periods), of which 53.3 t was stem yield and 4.4 t – panicle yield. The recorded yield of the same variety for sowing in the third decade of April is 1.5 t less – 68.1 t/ha. Stem and panicle weight was 55.5 t and 3.7 t, respectively. In Prysyvashskyi 85 variety, the total yield for sowing in the third decade of April was 2.2 t higher compared to the sowing option in May and amounted to 59.2 t/ha. In addition to the above, stem weight was 48.1 tons, and the panicle one – 7.4 tons. 5.4 thousand m3/ha of biogas and 8.5 t/ha of solid biofuel can be obtained from Dovista variety green mass for sowing in the third decade of April. Meanwhile, the energy output per area unit will be 118.3 and 136.5 GJ/ha, respectively. From the green mass collected in the second decade of September from Dovista variety for sowing in the third decade of April, 6.1 thousand m3/ha of biogas with an energy output of 132.9 GJ/ha and 9.5 t/ha of solid biofuel with an energy output of 153.3 GJ/ha. Green mass processing of the same variety obtained during sowing in the first decade of May will make it possible to obtain 5.8 thousand m3/ha of biogas and 8.3 t/ha of solid biofuel. To form the highest indicators of bioenergy, it is necessary to grow Dovista sugar sorghum variety. The green mass of plants can be collected during the third decade of August – the second decade of September. It is optimal to sow sugar sorghum in the first decade of May. Under such an agricultural technology scenario, biogas output can be 6.1 thousand m3/ha, solid fuel – 9.5–9.6 t/ha.