This study evaluated the impact of sowing dates on the growth, yield, and nutritive quality of three corn cultivars including Gwangpyeongok, Dacheongok, and Shinhwangok. Plant height and total yield components declined with delayed sowing across all cultivars. Gwangpyeongok achieved the highest plant height (289 ± 14 cm), grain yield (9,108 ± 82 kg/ha), and total yield (18,973 ± 2,560 kg/ha) at the April 29 sowing. Dacheongok recorded the highest stover yield (17,227 ± 137 kg/ha) and total yield (22,236 ± 1,053 kg/ha) on May 13. Shinhwangok reached its maximum total yield (19,158 ± 604 kg/ha) at May 13 but showed the sharpest declines by May 16. Nutritional quality also deteriorated with later sowing. In stover, crude protein (CP) declined to 3.58% in Shinhwangok at May 16, accompanied by a rise in neutral detergent fiber (NDF) to 69.9%. In contrast, Dacheongok maintained stable CP levels (5.27–5.60%) and the lowest fiber fractions. Gwangpyeongok exhibited the highest stover CP at April 29 sowing, along with the lowest NDF and acid detergent fiber (ADF) contents. Grain CP was highest in Gwangpyeongok (8.1 ± 0.4%) and Shinhwangok (9.6 ± 0.9%) at April 29, while Dacheongok showed its maximum grain CP (8.0 ± 0.3%) at the same sowing date, coupled with relatively low fiber content. Overall, the findings highlight that timely sowing is crucial for achieving both high yield and optimal nutritive quality in maize. For Gwangpyeongok and Dacheongok, sowing from late April to mid-May provided the best balance between yield and nutritional quality. In Shinhwangok, the highest stover, grain, and total biomass yields were obtained at the May 13 sowing.
The purpose of this study is to examine the effects of sowing dates on the growth, yield, and forage quality of two triticale cultivars, Joseong and Hanmiso-1ho. Field experiments were conducted with sowing dates ranging from September 25 to November 13, 2023. The results indicate that both cultivars and sowing date significantly influence growth characteristics, dry matter yield, and nutritional composition. The highest yields were obtained from the earliest sowing (September 25), with Joseong producing 10,979 ± 366 kg/ha and Hanmiso-1ho 12,201 ± 2,124 kg/ha. Yields remained relatively high on October 5 and 16 sowings but declined sharply after October 25, reaching the lowest levels on November 13 (Joseong 4,991 ± 458 kg/ha; Hanmiso-1ho 6,353 ± 338 kg/ha). Delayed sowing increased plant height but reduced forage biomass. Forage quality also varied with the sowing date. Crude protein (CP) ranged from 8–11%, with higher values in early sowing (10.7% for Joseong, 10.3% for Hanmiso-1ho) and lower at mid to late sowing dates. Fiber content such as NDF and ADF levels increased with the sowing dates delayed, but declined slightly with the November sowing dates. Overall, end September to early October sowings provide optimal yield and forage quality for both triticale cultivars.
Background: Portable, small computers and smartphones are now considered essential tools in modern society and smartphone ownership and usage rates are rising every year. However, excessive smartphone use can have musculoskeletal and postural implications, leading to “smartphone addiction” and related dysfunctions. Objects: This study aimed to investigate the effects of smartphone addiction on scapular position and muscle activity during shoulder abduction in asymptomatic individuals. Methods: A total of 45 participants were classified into high-risk, middle-risk, and low-risk groups based on their smartphone addiction levels. Scapular position was measured using the scapular index, round shoulder posture (RSP), lateral scapular slide test, and scapulohumeral rhythm spine angle. Muscle activity was assessed using electromyography of the upper trapezius (UT), lower trapezius (LT), serratus anterior (SA), and anterior deltoid (AD) muscles during shoulder abduction. Results: Smartphone addiction was significantly associated with altered scapular position and muscle activity. The high-risk group exhibited greater forward head posture and more pronounced RSP. Additionally, the high-risk group had lower SA activation and higher UT, LT, and AD muscle activity, indicating compensatory mechanisms due to altered scapular positioning. Conclusion: These findings suggest that excessive smartphone use contributes to postural deviations and altered muscle activation patterns, which may lead to musculoskeletal dysfunction over time. Clinicians should consider smartphone use when assessing patients with scapular dysfunction, and future studies should explore interventions to mitigate these effects.
Background: Hamstring shortness (HS) contributes to the limit of hip and knee range of motion and can limit the execution of multi-segmental movement exercises such as squatting, thereby altering the muscle activation. The double leg squat (DS) is fundamental exercise for knee injury rehabilitation programs. However, it may aggravate knee joint injury and cause low back pain. The Bulgarian split squat (BSS) is a one-leg squat exercise with greater knee joint stability than DS. Measuring muscle activation during the squat will provide insight into the contribution of hamstring activation and quadriceps and hamstring (Q:H) ratio to the knee in participants with HS. Objects: This study compares hamstring activation and Q:H ratios during squat exercises in individuals with and without HS. Methods: This study classified 30 healthy participants, based on active knee extension, into two groups: with HS and without HS. Surface electromyography was performed to determine muscle activation of the medial hamstring (MH) and biceps femoris of the hamstrings and coactivation of the Q:H. All participants performed DS and BSS. Results: MH activity was significantly higher in the with HS group than in the without HS group during all exercises, and the Q:H ratio was significantly closer to 1.0 during BBS compared to DS. Additionally, the with HS group had a significantly lower Q:H ratio than without HS group. Conclusion: In comparison between exercises, BBS can bring the Q:H ratio closer to 1.0 compared to DS, which may enhance knee stability. However, in between-group comparisons, the increased tension due to the shortening of the hamstrings leads to heightened hamstring activation, resulting in a Q:H ratio that is closer to 1.0 compared to the without HS group. Therefore, relying solely on the Q:H ratio to assess knee stability may be risky.
Climatic change affects agricultural, environmental and livestock production. Forage productivity is highly dependent on the weather change. The Pyeongchang region has more difficulty in cultivation of Sorghum-Sudangrass hybrids (SSH) than other warm regions because of the cold weather. This experiment was carried out to analysis the agronomic characteristics, productivity, and nutritive value of three cultivars of Sorghum-Sudangrass hybrids in the Pyeongchang region from 2021 to 2022. Two harvests were taken in each year, and the agronomic characteristics, dry matter yield, and nutrient content of the whole SSH crops were determined. The plant height ranged between 281-291 cm and 165-172 cm in the first and second harvest, respectively. Plant height of Superdan (291±49 cm) was the highest in the first cut and Dairy mens Dream (172±30 cm) was the highest in the second cut time. Stem diameter ranged from 9.5 to 8.8 mm with Superdan having a higher level than the other two cultivars. The Dairy mens Dream variety produced significantly higher dry matter yield (15,695 kg/ha) than those of Superdan (14,584 kg/ha) and Supergreen (14,300 kg/ha) over a two-year experimental period. In terms of nutritional quality, the crude protein content, neutral detergent fiber and acid detergent fiber of SSH cultivars were analysed. There were no significant changes in the content of CP, ADF and NDF ranges among the cultivars. In addition, the Superdan cultivar had slightly higher CP content (10.17%) and was followed by Dairy mens Dream (9.84%) and Supergreen (9.54%) in the second cut time of 2-year average. Dairy mens dream had lower ADF and NDF values than other cultivars; however, no significant differences amongst cultivars in fiber content were observed. Therefore, these three cultivars displayed the potential growth characteristics, DM yield and nutritive values in Pyeongchang region. Hence, the SSH cultivars have a potential to withstand the climatic change and improve SSH productivity in the study area.
배추는 한국에서 연중 소비되는 김치의 주 원료이며, 노지에서 주로 재배되고 있다. 온실 재배 수경재배 시 스템은 기후 변화에 영향을 받지 않고 토양을 대신한 배지를 사용함으로써 토양 병원균으로부터 작물을 보호할 수 있어 재배 안정성을 확보할 수 있다. 수경재배용 배지 중 일부는 재사용이 가능하고, 이러한 배지의 조성은 작물 생 장과 품질에 영향을 줄 수 있다. 본 연구는 재사용 코이어 배지 또는 인공배지를 첨가한 배지 조성에 칼슘 공급원을 처리하여 배추(Brassica rapa ‘Bulam Plus’)를 수경재배 했을 때 배액과 생육에 미치는 영향을 알아보고자 10주동 안 수행하였다. 배지 조성은 재사용 코이어: 피트모스: 펄라이트 비율(v/v/v)을 각각10:0:0, 7:2:1, 5:3:2의 세 처리 와 각 처리에 칼슘 공급원인 CaSO4(G)와 CaO(Q)를 200g/m2 혼합한 총6가지 처리(G10:0:0, G7:2:1, G5:3:2, Q10:0:0, Q7:2:1, Q5:3:2)하였다. 배액량, 배액의 pH와 EC, 생육, 잎끝마름(Tipburn)발생을 조사하였다. 배추 생육이 증가함에 따라 모든 처리에서 배액률은 감소하였고, 처리 9주째는 20% 미만으로 감소하였다. 배액의 EC는 G 처리가 Q 처리 보다 높았으나 배액의 pH는 Q 처리가 높았다. 처리 10주째 배추의 초장, 엽수, 엽폭은 처리 간 유의성이 없었다. 엽 록소함량값(SPAD)은 G7:2:1과 G5:3:2처리에서 높게 나타났다. 잎의 당도와 건물중은 Q5:3:2처리에서 높았으며, 건물 중이 관찰되었다. 배추의 잎끝마름 발생은 처리 25일째 관찰되었으며, G7:2:1처리에서 가장 높았다. 이상의 결과를 종합할 때 CaO가 첨가되고 재사용 코이어 50% 함유된 Q5:3:2처리에서 수경 재배된 배추 생육이 양호하였다. 본 연 구는 간이 시설을 적용된 수경재배 시스템에서의 안정적 배추 재배를 위해 재사용 코이어 배지와 칼슘 공급원에 관 한 기본 정보를 제공하고자 하였다.
The Pieris napi-complex in East Asia that comprises P. melete Ménétriés, 1857, P. dulcinea (Butler 1882), and P. nesis (Fruhstorfer 1909) has been taxonomically challenging to distinguish due to their similar appearances. In this study, P. nesis, typically found in central Japan, was discovered in the highlands on Jejudo Island, the southernmost part of the Korean Peninsula. We conducted a molecular phylogenetic analysis using mitochondrial COI gene to explore the relationship between P. dulcinea and P. nesis, and confirmed that P. nesis occurs in Korea. This paper provides the morphological characteristics of P. nesis compared to P. dulcinea, along with DNA data.
전세계적으로 50여종이 알려져 있는 Adrapsa속은 지금까지 한국에서는 2종이 알려져 있다. 이 연구에서는 Adrapsa notigera (Butler)를 국내 에서 처음으로 보고한다. 이 종의 형태학적 특징과 유사종과의 차이, 분포지역, 성충 및 생식기 사진을 제공하며 유전학적 정보를 통하여 속 내 다른 종과의 분류학적 관계에 대해서도 고찰한다.
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.
The world is transitioning towards sustainable agriculture, which includes reducing chemical fertilizers and increasing the adoption of eco-friendly materials. Red clay, known for its colloidal properties, adsorption, and ion exchange capabilities, has become eco-friendly due to its non-toxic nature. However, when red clay is applied in its insoluble powdered form, its absorption by plants is limited. Processed red clay (PRC) was developed to overcome these limitations, and microbial formulations containing Lactobacillus fermentum (MFcL) were applied alongside it. Chlorophyll content and fluorescence values decreased over time after cucumber transplantation. However, co-application of PRC and MFcL resulted in higher chlorophyll content than PRC alone, suggesting that this combination could alleviate plant growth reduction caused by stress. Although the total yield of cucumbers was highest in the NF group, yield per plant increased by more than 10% in the PRC treatment compared to NF. Additionally, yield was higher when PRC was applied alongside MFcL than with MFcL alone. While the proportion of marketable fruits decreased over time in the NF treatment, it increased in the PRC treatment. Soil analysis revealed that PRC application increased soil pH by 3% and available silicon content by 7.6% compared to NF, while available phosphate levels decreased by 13%. Analysis of microbial density in the soil showed that bacteria levels significantly increased by 2-fold in PRC+MFcL compared to NF, while actinomycetes decreased by 1.5-fold. In conclusion, PRC treatment positively influenced cucumber growth, and co-application with microbial fertilizers demonstrated a synergistic effect.
Corn is essential for both humans and animals. The crop is the third most important food crop after rice and wheat. A rise in farming is resulting in a lack of self-sufficiency of high quality forages. Therefore, corn cultivars in Korea must be optimized to increase productivity and yield. A study was conducted in Pyeongchang, South Korea between 2021-2022 to evaluate the characteristics and productivity of three corn cultivars: Kwangpyeongok, AGR 41, and Nero IT. Different varieties of corn were sown in Pyeongchang on April 29 and April 27 of 2021 and 2022, respectively. The productivity and characteristics of the cultivars Kwangpyeongok, AGR 41, and Nero IT were evaluated during the yellowing ripening stage. The characteristics included the leaves, stems, grain, and stover content. Across different corn cultivars, there was no significant difference in stem height, diameter, forage or grain quantity based on an average of two years. Yet, significant differences were noted in the stem heights of all cultivars between 2021 and 2022 (p<0.05). There was a significant difference in the diameters of Kwangpyeongok and Nero IT between 2021 and 2022. A significant difference in forage yield was observed for Nero IT between 2021 and 2022. The yield of grains and forages was higher in 2021 than in 2022, which could be attributed to temperature and precipitation variations. We can conclude from these data that all cultivars in Pyeongchang showed significant productivity and yield, which could be useful to produce nutrient rich silage for livestock.