Productivity of Sorghum-Sudangrass Hybrids in Cheonan Central Region, Korea

Forage crop cultivation and management are the greatest challenge under warm and dry climatic conditions. In this study, we estimated the productivity of three Sorghum-Sudangrass hybrids (SSH) cultivars in Cheonan, Korea, under different weather conditions during 2021-2023. The selected three cultivars performed well in the first and second cutting time during the experimental period and the plant growth characteristics were slightly different among cultivars. Particularly, the plant height was highest in Superdan cultivars (282 ± 24, 271 ± 30 cm), followed by Dairy mens dream (263 ± 39, 283 ± 29 cm) and Supergreen (270 ± 36, 264 ± 34 cm), for the first and second cuts respectively. The stem diameter slightly decreased in the second cut compared with the first cut of SSH cultivars. The highest stem diameter was found in Superdan cultivars (11.1 ± 1.7 mm), greater than Supergreen (10.2 ± 1.7 mm), and Dairy mens dream (9.5 ± 1.8 mm). Also, the total dry matter yield (DMY) was highest in Dairy mens dream (28,868 ± 6,653 kg/ha) followed by Supergreen and Superdan cultivars. In 2021 and 2023, the highest plant height, stem diameter and DMY were measured in the selected cultivars compared to 2022. The crude protein level was higher in the first cutting of all three cultivars at approximately 9-12%, in the order of Supergreen > Dairy mens dream > Superdan varieties. Moreover, the crude protein content was lowest in the second harvest of all cultivars, but the NDF and ADF levels did not alter in both harvest periods across different cultivars and years. In conclusion, the selected cultivars for SSH forage production could be efficient and recommended in the Cheonan region. However, the choice of cutting time and optimum precipitation should be considered to further increase SSH forage cultivation.