Italian ryegrass (Lolium multiflorum Lam.) is one of the most widely grown winter forage crops in Korea, but its yields are known to be greatly affected by drought that occur frequently in spring. This study aimed to compare the growth and tolerance response characteristics to drought stress in several Italian ryegrass varieties cultivated in Korea. Twenty-day-old Italian ryegrass was subjected to drought treatment for 4 days, and then the growth and physiological responses of the plants were compared. Drought stress reduced leaf length, fresh weight, and dry weight in all Italian ryegrass varieties compared to the control. In addition, chlorophyll content was significantly decreased in all varieties treated with drought stress, but Fv/Fm was significantly decreased only in Winter hawk. For H2O2 and malondialdehyde (MDA) contents, Winter hawk showed the highest increase and New dawn showed the least increase. In terms of relative water content (RWC), New dawn showed the least decrease and Winter hawk showed the greatest decrease. These results indicate that New dawn is relatively drought-tolerant and Winter hawk is a drought-sensitive variety, indicating that each variety of Italian ryegrass has different drought tolerance mechanisms, which may provide basic insight for the development of tolerant varieties in the future.
Due to climate change and the expansion of cultivation areas through the use of reclaimed land, changes in the selection of Italian ryegrass (Lolium multiflorum L.) varieties are anticipated. This study was conducted to compare the growth characteristics before overwintering, productivity, and feed value of eight Italian ryegrass varieties with different maturing stages under the same cultivation conditions. The variety ‘Lm4ho’, a medium-maturing type, showed superior growth characteristics before overwintering, including plant height, leaf length, and leaf width. The heading date was advanced in all varieties, with a greater degree of advancement observed in varieties with earlier heading dates. When harvested at the heading stage of the early-maturing types, the dry matter yield of the medium-maturing types was not significantly different from that of the early-maturing types. However, when harvested at the heading stage of the medium-maturing types, the dry matter yield was higher than that of the early-maturing types. Specifically, ‘Lm4ho’ produced 2,518 kg/ha more than ‘Kowinearly’. The late-maturing variety IR901 and the medium-maturing varieties ‘Lm4ho’ and ‘Kowinmaster’ showed statistically superior dry matter yields. In terms of forage value, including crude protein (CP), total digestible nutrients (TDN), and relative feed value (RFV), the medium- and late-maturing types outperformed the early-maturing types. Notably, ‘Lm4ho’, ‘IR 901’, and ‘Hwasan 104’ were evaluated as suitable varieties for high-quality forage production. These results suggest that medium-maturing varieties may be suitable for double cropping in the central regions due to climate change. We propose that future breeding of Italian ryegrass should expand from focusing on cold tolerance and early-maturing varieties to include mediumand late-maturing varieties that consider both productivity and quality.
Rapeseed (Brassica napus L.) oil is mostly refined oil (RO). However, with increasing interest in health, the consumption of cold-pressed oil (CPO) without chemical refining is increasing in Korea. In this study, quality characteristics of CPO from rapeseed varieties ‘Jungmo7001’, ‘Jungmo7002’, ‘Jungmo7003’,and ‘Yuryeo’were evaluated and compared with RO, a commercial product. L-value and a-value were lower while b-value was significantly higher for CPO than those for RO. Analysis of fatty acid compositions of each oil revealed that CPO from ‘Yuryeo’contained the highest oleic acid at 74%. Analyses of contents of bioactive compounds in CPOs and RO revealed that contents of tocopherol, β-carotene, and canolol were the highest in CPOs from ‘Jungmo7003’, ‘Jungmo7002’, and ‘Jungmo7001’at 55.5, 0.3, and 0.2 mg/100 g, respectively. In addition, CPOs contained higher contents of bioactive compounds than RO, suggesting that CPO could provide health benefits. The induction period of CPOs measured using Rancimat were 9∼52% longer than that for RO, indicating that CPOs had a higher oxidative stability under given conditions. These results could be used to obtain basic data on quality of domestic rapeseed varieties.
This study was conducted in Cheonan, the middle region of South Korea, to evaluate the forage characteristics of six medium maturing Italian ryegrass varieties: ‘Kowinmaster’, ‘IR 601’, ‘IR 602’, ‘IR 603’, ‘IR 604’ and ‘IR 605’. In growth characteristics, 'Kowinmaster' exhibited the earliest heading date on April 30, while 'IR 601' exhibited the latest on May 17. 'IR 601' exhibited the highest lodging resistance, and all varieties demonstrated excellent disease resistance, waterlogging tolerance, and cold tolerance. 'IR 603', 'IR 604', and 'IR 605' demonstrated above-average plant length, with 'IR 604' reaching the longest at 114.8 cm. In productivity, 'IR 602' and 'IR 605' produced the highest total dry matter yield, each exceeding 12,800 kg/ha. Regarding feed values, 'Kowinmaster' recorded the highest RFV and TDN at 119.18 and 66.07%, respectively, with 'IR 605' exhibiting the second highest. 'IR 604' and 'IR 601' demonstrated crude protein concentrations over 9%, with 'IR 604' exhibiting the highest at 9.74%. Analysis of monosaccharide content in Italian ryegrass revealed that 'IR 605' exhibited the highest glucose and fructose content at 23.35 g/kg and 50.70 g/kg, respectively. In summary, 'IR 602' exhibited the highest productivity, 'Kowinmaster' recorded the highest feed value, and 'IR 605' exhibited the highest glucose and fructose content. Therefore, 'IR 605' is considered the most outstanding variety due to its superior productivity, second highest feed value, and significant monosaccharide content.
Fall armyworm (FAW, Spodoptera frugiperda) is a major pest worldwide, and since its first domestic invasion was confirmed in 2019, its damage has been steadily increasing in crops such as corn until recently. In order to provide basic data for the management of FAW, we conducted a comparison of host preference and nutritional composition analysis of corn varieties. A total of 12 varieties of corn were selected for the experiment. To investigate the preference among the varieties, we examined the host preferences at the population level and the individual level, and found no statistically significant differences. In the population-level experiment, the highest damage rate was observed for Saekso 4 and the lowest for Heukgeom 2. In the individual-level experiment, the highest damage rate was found for Kangilok and the lowest for Oryun 2 when using leaves, and the highest for Saekso 1 and the lowest for Dreamok when using stems. As a result, the population-level and individual-level results were not consistent, suggesting that FAW's corn variety preference is not clear and may vary depending on various conditions such as corn tissue. Composition analysis of the 12 varieties showed no correlation between composition and FAW preference among the varieties, and considering the feeding behavior of FAW, which are highly polyphagous, it is recommended to control FAW as early as possible to improve control effectiveness.
This study aims to distinguish between various Ethiopian durum wheat varieties based on their genetic identity using chemical and morphological characterization of seeds. Combinatorial employment of five chemical tests on seeds showed marked qualitative variation among the test varieties, with high discriminatory potential noted for the standard phenol test, followed by the modified phenol and iodide tests. The modified phenol test was instrumental in further discriminating between the varieties that were not identified using the standard phenol test. Unlike the iodide and phenol tests, the NaOH and KOH tests did not show significant variation among the varieties. These results underscore the efficacy of phenol and iodide tests in differentiating between durum wheat varieties. Although the morphological traits were advantageous in seed characterization, they lacked discriminatory power compared with that of the chemical tests. This study concludes that a single test is inadequate for varietal discrimination; rather, a combination of chemical tests can augment the discriminatory potential.
European and Turkish rice varieties were analysed to identify the traits associated with low-temperature germination. The aim of the study is to develop new rice varieties that can use these traits to reduce greenhouse gas emissions in rice fields. The average low temperature germination ratio (GR) in the European and Turkish rice varieties was 89.0±14.1%. The speed of the germination rate (SG) in Korean early maturing varieties, ‘Jopyeong’ and ‘Baekilmi’ was 1.3 and 3.5, respectively, whereas the European and Turkish varieties had a SG of 6.6. In terms of germination energy (GE) by the date, the European and Turkish varieties started germination within 4 days, while ‘Jopyeong’ and ‘Baekilmi’ began to germinate after 8 and 10 days, respectively. The mean germination time (MGT) for the European and Turkish varieties was 9.9±1.2 days. Between 4 to 10 days after inoculation, the germination velocity coefficient (GVC) for the European and Turkish varieties increased moderately from 2.6 to 5.3. After 10 days, the GVC rose rapidly from 7.0 to 12.0. ‘Jopyeong’ and ‘Baekilmi’ had slower germination rates compared to the European and Turkish varieties, in which the GVC increased moderately to 3.2 and 2.3, respectively, between 7 and 9 days after inoculation. The average mesocotyl elongation ability was 4.0±0.4 cm, with a range from 1.3 cm to 7.3 cm.
Since maize (Zea mays L.) originated in central and south America, it requires warm climate conditions throughout its growing season. Growth halts when night-time temperatures drop below 10℃, and the plant may die if temperature reach -1.7℃. Thus, temperature should be maintained between 10 and 30℃ from seeding to maturity. The germination temperature for maize should be at least 8-11℃, whit an optimal range 32-34℃. Since temperature significantly affects the germination rate and period, it plays a crucial role in maize growth. In this study, we evaluated the quantity and feed value of 11 major varieties to determine those best suited for maize cultivation as feed in higher latitude, specifically in Democratic People’s of Republic of Korea, below 38 degrees north. A cultivation test was also conducted in Suwon in Republic of Korea, to assess adaptability in areas south of Mt. Suyang. Among the varieties tested, Shinhwangok2 reached silking the fastest, in 65 days, while Gwangpyeongok took the longest at 75 days. The stem length of all varieties exceeded 230 cm. Gwangpyeongok had the tallest stems, while Daanok and Shinhwangok2ho displayed the highest ear ratios. Dacheongok presented the highest values in both dry matter and TDN quantity, with 31,420 kg/ha and 21,66 kg/ha respectively. Pyeonggangok had the highest crude protein content at 8.0%. TDN (%) ranged from 57-68%, with Hwangdaok reaching up to 68%. Based on these findings, Dacheongok and Pyeonggangok appear to be the most suitable varieties for cultivation in terms of both quantity and feed value.
Dried apple jeonggwa, a traditional Korean dessert, was made using various apple varieties, such as Jonathan, Fuji, and Hongro. After making the dried apple jeonggwa, the physical and sensory properties of the dessert made using different apple varieties were compared. The apple varieties had no differences in moisture content, weight loss, or sugar content. Chromacity differences were observed depending on the varieties, but E was small. Hardness was highest in Jonathan, while resilience was highest in Fuji, but there was no significant difference in hardness. In the sensory evaluation, appearance, color, sweetness, hardness, chewiness, and overall acceptability were highest in Jonathan, while there was no substantial difference among the varieties in terms of flavor, sourness, or adhesiveness.
This study aims to analyze the sensory characteristic of cooked rice made with 10 types of rice varieties produced in South Korea using descriptive analysis. Twelve subjects who cook rice regularly, at least once a week, were recruited for the study and participated as descriptive panelists. A total of 29 descriptive terms were developed to describe the sensory characteristics of cooked rice. The findings showed that there were significant differences in the sensory attributes, specifically the appearance and texture attributes among the rice varieties. Among the varieties, Haedeul, Ilpum, and Koshihikari were observed to have a large quantity of rice germ and a relatively yellowish appearance. In contrast, Samkwang, Chamdream, and Yeonghojinmi were relatively whiter than the other samples. Odae, Saecheongmoo, and Sindongjin were rated high in the attributes of roughness, hardness, and chewiness, and Jinsang was rated high in moisture, bitterness, stickiness, and wholeness of rice grains. The differences in the appearance and texture of these rice varieties are likely to significantly impact consumer preferences. Furthermore, the development of customized menus based on the sensory characteristics of the different varieties of rice could encourage consumers to purchase these varieties.
Drosophila suzukii (Diptera, Drosophilidae) can damage thin-skinned fruits (plums, cherries, peaches, blueberries, and strawberries) by laying eggs inside the fruit. In this study, a basic experiment was conducted to investigate the preference of D. suzukii to export table grape varieties. Four varieties of grapes (Kyoho grape, Shine muscat, Campbell grape, and Black sapphire) were placed in a cage containing more than 2,500 number of D. suzukii adults for 6, 8, 10, 12, and 24 hours and the egg-laying in grape has been induced. After 2 weeks, the number of pupae that emerged was counted. As a result, the largest number of pupae was generated in Kyoho grape among the four types of grapes, indicating that D. suzukii prefers to lay egg in Kyoho grape. Through this experiment, it was determined that 6 h was the appropriate inoculation time, and then an inoculation experiment was conducted on Kyoho grape. The total weight of the Kyoho grape used in the experiment was 36.119 kg, and a total of 2594 pupae were generated. The average number of D. suzukii per cluster was about 50. All stages of D. suzukii treated with low temperature(1℃) for 10 days were completely controlled.
This study was carried out to determine the sprouting period of early and mid-season varieties, which includes ‘Atlantic’, ‘Chubaek’, and ‘Superior’, during the summer storage period in a semi-underground warehouse without cooling system. And also it was investigated the effect of chlorpropham [Propan-2-yl N-(3-chlorophenyl)carbamate, CIPC] treatment on the sprouting inhibition for the varieties. This study was conducted to figure out a sprout inhibitory effect when CIPC was applied to 1kg of the potato tubers at concentrations of 10 mg and 20 mg which are lower than the treatment concentrations of ca 30 mg prescribed by the positive list system (PLS). The internal temperature of the warehouse used in this experiment was lowered by 5°C or more than the outside temperature. The difference between the lowest and highest temperature during the experiment throughout the day was 5°C. It showed the effect of reducing to 1/2 of the difference in outdoor temperature. As for the sprouting of potatoes, the extremely early variety ‘Chubaek’ sprouts appeared at the 6th week of storage of control and it was the fastest sprouting potato among the control groups of the varieties. Sprouting began to appear in the Superior at the 6th week of storage, while the ‘Atlantic’ sprouted at the 8th week of storage. The appearance of sprouts was suppressed in all treatment groups of ‘Atlantic’ and ‘Superior’ varieties in CIPC treatments. Sprouts were observed in all treatment groups of ‘Chubaek’ after the 7th week, but the elongations of the sprouts in tubers were completely inhibited until the 8th week of storage. ‘Atlantic’ and ‘Superior’ seemed to have a sprouting inhibitory effect even with a low CIPC concentration of 10 mg·kg-1, with the exception of extremely early variety ‘Chubaek’ that breaks out of the dormancy quickly. Although weight loss occurred continuously during storage, it was minor loss of 0.7-1.6%. There was no consistent trend for changes of the loss in the varieties and CIPC treatments. Most common pathological disorder was the dry rot during the experiment, but only few were affected. The use of the tubers treated at 18°C and 90% RH for 10 days and the rack of refrigeration system which lead to lack of convection seemed to have suppressed the spread of pathogens.
본 연구는 새만금 간척지와 주산지인 무안에서 재배하였을 때 양파의 생육과 퀘르세틴 등 기능성 성분을 분석하였다. 양파는 중생종 품종인 ‘맵시황’, 중만생 품종인 ‘선파워’, ‘헬시큐’를 사용하였다. 전남 무안에 9월 상순 파종 후 육묘하여 간척지와 무안에 각각 11월 상순에 정식하고 이듬해 6월 초순에 수확하였다. 중만생종 품종인 ‘선파워’와 ‘헬시큐’가 간척지에서 구중 336.5g, 248.3g으로 생육이 우수하였다. 피루브산은 ‘헬시큐’, ‘맵시황’, ‘선파워’ 순으로 높았고 지역 별로는 ‘헬시큐’, ‘맵시황’ 품종이 간척지 재배 시 각각 48.3μmol·g-1, 41.1μmol·g-1으로 무안에서 재배하였을 때보다 높았다. 총 퀘르세틴은 품종 별로 비교하였을 때 ‘헬시큐’가 219.1μg·g-1으로 가장 높았고 ‘선파워’, ‘맵시황’의 순이었으며 재배지역에 따른 차이는 확인되지 않았다. 또한 총 페놀은 총 퀘르세틴 함량과 유사한 경향을 보였으며, ‘헬시큐’의 함량이 853.7μg·mL-1으로 가장 높았고, ‘선파워’는 무안에서 재배할 경우 페놀 함량이 높은 것으로 나타났다. 결과적으로, 피루브산, 총 퀘르세틴, 총 페놀의 함량은 재배지역 보다는 품종에 따른 영향이 큰 것으로 판단되었다.