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.

Sorghum-Sudangrass hybrids (SSH) is a grass cereal hybrid crop with a high yield potential under different climatic conditions. The aim of this study was to evaluate the growth characteristics, dry matter yield and nutrient content of the SSH cultivars such as Dairy Mens Dream, Superdan and Supergreen from 2021 to 2023 in Jeju Island, Korea. Among the three cultivars, Superdan grew significantly taller with a larger stem diameter at both harvest times. In contrast, Dairy Mens Dream had least height and less stem diameter, but the dry matter yield was greater for Dairy Mens Dream than other cultivars. Furthermore, the crude protein content at the first cut was higher than 8.5% compared to the second cut (6.5 – 7.0%). The neutral detergent fiber (NDF) and acid detergent fiber (ADF) content was higher in the second harvest of all cultivars compared to the first harvest of SSH in 2021. The SSH cultivation in 2021 and 2023 had higher ADF and NDF content than in 2022, possibly due to the average precipitation and optimum temperature suitable for SSH production in 2021 and 2023. The selected three SSH cultivars showed significant growth characteristics, dry matter content, and nutritional value. The overall data suggested that all three SSH showed significant productivity and nutritional content in the Jeju region of sub-tropical climatic condition.

본 연구는 무인기를 이용한 동계사료의 수량조사시 필요한 검량식의 작성을 위한 식생조사 및 분광측정의 적정 시기와, 작성된 검량식의 적용이 적절한 시기를 판단하기 위하여 고정식 자동 분광 측정장치를 개발하여 호밀, 총체보리, IRG를 대상으로 NDVI 를 장기간 측정하였다. 그리고 NDVI가 최댓값이 되는 날을 기준 으로 증가기간과 감소시간으로 기간을 나누어 건물수량 예측을 위한 검량식을 작성하고 검량식의 예측정확도를 각각 비교하였다. 조사결과 호밀, 총체보리, IRG는 각각 4월 8일, 4월 9일, 4월 5일에 NDVI가 최대치가 되었으며 NDVI 증가기간의 검량식은 결정계수(R2)는 각각 0.84, 0.84, 0.78로 높은 상관관계를 보였고 NDVI 감소기간에는 각각 0.00, 0.02, 0.27로 매우 낮게 나타났다. 따라서 NDVI 측정을 통한 건물수량 예측을 효율적으로 하기 위해서는 NDVI 변화를 정확히 측정할 필요가 있으며 고정식 자동 분광 측정 방법은 생육에 따른 NDVI의 정밀 측정에 효과적인 것으로 판단된다.

This study was carried out to investigate the properties of soil and water under Double-cropping SSH followed by whole crop barley (SSFWB) or by Hairy vetch (SSFHV) in paddy land. A field study was conducted at Baeksan-myeon, Kimje, Jeonbuk province in Korea on clay loam soil for 3 years. All plots were arranged in completely randomized design with three replicates. The pH and the contents of T-N and organic matter (OM) in soil samples collected at the end of the experiment were remarkably higher t㏊n those at the beginning of the experiment in both SSFWB and SSFHV treatment (P＜0.05). The contents of an exchangeable cations at the end of the experiment were remarkably higher t㏊n those at the beginning of the experiment in both SSFWB and SSFHV (P＜0.05). And then, the concentration of NO₃-N, NH₃-N and PO₄-P in discharge and leaching water were not influenced by the cropping system