B. Ahn, Jin-Ho Jang, Do-Young Ko, Hyo-jin Kim, Chang Soo Kim, Jinho Kim, Yee-Jin Lee
{"title":"Influences of N, P 2 O 5 and K 2 O fertilizer application amounts on growth of Houttuynia cordata Thunb and soil properties","authors":"B. Ahn, Jin-Ho Jang, Do-Young Ko, Hyo-jin Kim, Chang Soo Kim, Jinho Kim, Yee-Jin Lee","doi":"10.7744/KJOAS.20170020","DOIUrl":"https://doi.org/10.7744/KJOAS.20170020","url":null,"abstract":"We conducted this study to determine the recommended application rate of fertilizer for Houttuynia cordata Thunb cultivation. The effects of various application levels of N, P₂O₅, and K₂O fertilizers on the growth of this plant were investigated and the associated changes in soil properties were evaluated in the field. Soil pH at harvest time of Houttuynia cordata Thunb did not differ from that before fertilization, whereas EC tended to decrease during cultivation. The soil organic matter (SOM) and available phosphorus increased after treatment, and the amount of applied fertilizer (P₂O₅) and available phosphorus were proportional. The nitrogen absorption amount increased in N 100% treatment, but decreased in N 150% treatment. The phosphorus absorption amount rose with the fertilizer treatment concentration until P₂O₅ 150% treatment. The amount of absorbed potassium decreased in treatments with K₂O 150% and K₂O 200%. The plant length was the longest in N 100%, P₂O₅ 150%, and K₂O 200%. The stem diameter was estimated to be 3.46 - 3.67 ㎜ in N 100 - 200% treatment, 3.55 - 3.67 ㎜ in P₂O₅ 100 - 150%, and 3.79 ㎜ in K₂O 200%. The number of tillers did not differ amongst fertilization treatments. The fresh weight was summed to be 3.67 ton/10 a in N 100% treatment, 3.79 Mg/10 a in P₂O₅ 150%, and 3.83 Mg/10 a in K₂O 150%. Thus, the relationship between the fertilizer amount and yields of the plant showed that the most economical quantity of fertilizers should be 10.2 N ㎏/10 a, 5.5 P₂O₅ ㎏/10 a, and 8.2 K₂O ㎏/10 a for Houttuynia Cordata Thunb.","PeriodicalId":17916,"journal":{"name":"Korean Journal of Agricultural Science","volume":"17 1","pages":"211-220"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78321901","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Effect of different pollen sources on fruit characteristics and quality in ‘Niitaka’ pears (Pyrus pyrifolia Nakai)","authors":"U. Lee, Young-Jik Ahn, J. Chun","doi":"10.7744/KJOAS.20170003","DOIUrl":"https://doi.org/10.7744/KJOAS.20170003","url":null,"abstract":"This study was conducted to explore which pollen type could be an effective pollen source for self-incompatible ‘Niitaka’ pear (Pyrus pyrifolia Nakai), when different pollinizers were to be applied. The pollens of five different pears with similar flowering times were applied to bagged ‘Niitaka’ flowers grown in Cheonan city, Korea. Pollen types used were of different origins including Korean pears (‘Wonhwang’ and ‘Chuhwangbae’), Japanese pears (‘Chojuuro’ and ‘Okusankichi’), and Chinese pear (‘Yali’). Results show that the amount of pollen produced by flowers of each cultivar was the largest in Korean pear ‘Wonhwang’ (234 g/100 flowers) and the smallest in Japanese pear ‘Okusankichi’ (126g/100 flowers). A high proportion of large fruits (> 600 g), 71.4% of total production, was found in the fruits treated with ‘Yali’ pollen. However, these fruits showed an unfavorable external appearance. Based on individual fruit width differences, ‘Chojuuro’ treatment produced the smallest difference in fruit diameters (3.2 mm) and ‘Yali’ treatment’ gave the largest (4.8 mm). Also, the difference in fruit length was the largest in ‘Yali’ (7.5 mm), which also produced the most uneven fruits among the pollinizers used. Meanwhile, the use of pollens of ‘Wonhwang’ and ‘Chuhwangbae’ improved productivity by increasing the fruit shape index and the ratio of bigger fruits in total production. Moreover, those pollens also decreased the development of lenticels on fruit skins which gave them a smoother appearance.","PeriodicalId":17916,"journal":{"name":"Korean Journal of Agricultural Science","volume":"19 1","pages":"23-29"},"PeriodicalIF":0.0,"publicationDate":"2017-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85179390","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. B. Bo, O. Won, H. T. Sin, Jeung Joo Lee, K. Park
{"title":"Mechanisms of herbicide resistance in weeds","authors":"A. B. Bo, O. Won, H. T. Sin, Jeung Joo Lee, K. Park","doi":"10.7744/KJOAS.20170001","DOIUrl":"https://doi.org/10.7744/KJOAS.20170001","url":null,"abstract":"In major field crops, synthetic herbicides have been used to control weeds worldwide. Globally, herbicide resistance in weeds should be minimized because it is a major limiting factor for food security. Cross resistance can occur with herbicides within the same or in different herbicide families and with the same or different sites of action. Multiple resistance refers to evolved mechanisms of resistance to more than one herbicide (e.g., resistance to both ALS-inhibitors and ACCase-inhibitors) and this resistance was brought about by separate selection processes. Target site resistance could occur from changes at the biochemical site of action of one herbicide. Non target site resistance occurs through mechanisms which reduce the number of herbicide molecules that reach the herbicide target site. There are currently 480 unique cases (species × site of action) of herbicide resistance globally in 252 plant species (145 dicots and 105 monocots). To date, resistance in weeds has been reported to 161 different herbicides, involving 23 of the 26 known herbicide sites of action. Finally, it can be concluded that we can protect crops associated to herbicide resistant weeds by applications of biochemical, genetic and crop control strategies.","PeriodicalId":17916,"journal":{"name":"Korean Journal of Agricultural Science","volume":"168 1","pages":"1-15"},"PeriodicalIF":0.0,"publicationDate":"2017-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80585140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
K. Hwang, Sunghoon Jung, K. Chul, Chung, Doug Young, K. Park
{"title":"Occurrence and distribution characteristics of weed species in organic paddy fields","authors":"K. Hwang, Sunghoon Jung, K. Chul, Chung, Doug Young, K. Park","doi":"10.7744/kjoas.20170048","DOIUrl":"https://doi.org/10.7744/kjoas.20170048","url":null,"abstract":"This study was conducted to investigate the dominance and distribution of weed species in organic and conventional paddy fields. The organic paddy fields were maintained for organic farming for more than five years in Anseong, Gyeonggi province of Korea. According to the Braun-Blanquet method, 42 and 36 weed species were found in the organic paddy fields in 2015 and 2016, respectively, while 38 and 36 weed species were found in the conventional paddy fields in 2015 and 2016, respectively. As a result of two years’ survey, 53 species from 24 families in the organic paddy fields were identified and classified as 32 annuals, 3 biennials and 18 perennials. In conventional paddy fields, 51 species from 24 families (30 annuals, 6 biennials, and 15 perennials) were identified. According to the classification by family, the most abundant weed species were Compositae (9 species), followed by Poaceae (8 species) and Polygonaceae (6 species) in organic paddy fields. In conventional paddy fields, Compositae (9 species) were the most abundant weed species, followed by Cruciferae (6 species), Poaceae, Polygonaceae, and Cyperaceae. This result indicates that the difference in diversity of weeds in paddy fields was influenced more by the agricultural environment than the type of cultivation. Our results could be used as a base data to control the occurrence of weed species in the paddy fields.","PeriodicalId":17916,"journal":{"name":"Korean Journal of Agricultural Science","volume":"14 1","pages":"325-331"},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88420115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Enhancing the accounting record keeping practices of advanced agricultural managers: Policy implications","authors":"Suhwan Myeong, Seungjee Hong, Min-su Yeo","doi":"10.7744/kjoas.20170015","DOIUrl":"https://doi.org/10.7744/kjoas.20170015","url":null,"abstract":"The purpose of this study was to investigate the status of agricultural management accounting information, education status, and policy demands through a questionnaire survey of advanced agricultural managers. These people are expected to play a key role in the changing agricultural environment in Korea. Based on survey results, several policy implications were derived for the advanced agricultural managers’ agricultural management accounting information record activation. Survey results of 303 respondents identified that 63.4% of them record their agricultural management accounting information. The biggest reason given for not recording this information was lack of time for record keeping. The biggest problem was a ‘lack of Question and Answer system’. In addition, 37.2% of the respondents were not aware of the current agricultural accounting guidelines. In terms of education, 71.3% of the respondents have completed course work in accounting and responded that an ‘On-off parallel education system’, which offers both online and offline classes, was the most effective method to prevent dropout. Respondents thought that agricultural management accounting records were helpful for the management of agriculture and their participation in government policies. They also thought that customized education programs should be further implemented for enhancing the effectiveness of education programs, and ‘One-stop Question and Answer system on related web sites and organizations’ is required for them to keep better records. The following policy implications can be derived from the survey results. First, interoperability between agricultural management accounting information recording programs is needed. Second, accessibility should be strengthened. Third, the education system needs to be improved. Fourth, voluntary participation should be encouraged. Last, the government needs to establish a post-verification system.","PeriodicalId":17916,"journal":{"name":"Korean Journal of Agricultural Science","volume":"6 1","pages":"133-143"},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80265073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Effect of biochar application on growth of Chinese cabbage (Brassica chinensis)","authors":"Oh Taek-Keun, Jae-Han Lee, Su-Hun Kim, H. Lee","doi":"10.7744/kjoas.20170039","DOIUrl":"https://doi.org/10.7744/kjoas.20170039","url":null,"abstract":"Biochar has the ability to mitigate climate change, improve crop productivity, and adsorb various contaminants. The aim of this work was to confirm the effect of biochar as a soil amendment on growth of Chinese cabbage ( Brassica chinensis ) using a pot experiment. Biochar was produced from residual-wood burnt at a pyrolytic temperature of 400 ℃ and consisted of 51.6 % carbon (C) by mass. The biochar was added to the soil at 0, 1, 3, and 5% by weight, which represent about 0, 18, 54, and 90 t ha -1 , respectively. The treatments were arranged in a randomized complete block design with 3 replications. The Chinese cabbage was grown for 49 days in a glasshouse in pots filled with sandy loam soil. Experimental results showed that the residual-wood biochar used for the experiment was slightly alkaline (pH 7.5). The fresh weights of Chinese cabbage were 86.22 g, 84.1 g, 63.23 g and 70.87 g, respectively, for biochar applications at 0, 18, 54, and 90 t ha -1 . Compared with the control (i.e., no biochar), biochar application increased soil pH and electrical conductivity (EC). Addition of biochar (54 and 90 t ha -1 ) to sandy loam soil had no effect on growth of Chinese cabbage. This might be due to excessive increase of soil pH from the biochar application, leading to reduced availability of plant nutrients. Based on these results, the authors conclude that an excessive addition of biochar may have negative effects on the healthy growth of Chinese cabbage.","PeriodicalId":17916,"journal":{"name":"Korean Journal of Agricultural Science","volume":"53 1","pages":"359-365"},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76247315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Koo, Dae-Sik Kim, Hee-Dong Koo, Han J. Lee, Bum‐Jin Park, Kyoung-chan Kim
{"title":"A case study on the economic feasibility of different patterns of green care and healing complexes","authors":"S. Koo, Dae-Sik Kim, Hee-Dong Koo, Han J. Lee, Bum‐Jin Park, Kyoung-chan Kim","doi":"10.7744/kjoas.20170033","DOIUrl":"https://doi.org/10.7744/kjoas.20170033","url":null,"abstract":"Korean agriculture has recently focused on the 6th dimension of industrialization, which includes the functions of healing and care. The green care and healing business is one of the most representative models, satisfying modern consumers' needs for care or healing in rural agricultural environments...","PeriodicalId":17916,"journal":{"name":"Korean Journal of Agricultural Science","volume":"20 1","pages":"451-461"},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82362514","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Changes in in vivo ruminal fermentation patterns and blood metabolites by different protein fraction-enriched feeds in Holstein steers","authors":"C. Choi","doi":"10.7744/KJOAS.20170038","DOIUrl":"https://doi.org/10.7744/KJOAS.20170038","url":null,"abstract":"The present study was conducted to investigate the effects of different dietary proteins as fraction-enriched protein, defined by Cornell net carbohydrates and protein system (CNCPS), on in vivo ruminal fermentation pattern and blood metabolites in Holstein steers fed total mixed ration (TMR) containing 17.2% crude protein. Four ruminally cannulated Holstein steers in a 4 × 4 Latin square design consumed TMR only (control) and TMR with rapeseed meal (AB1), soybean meal (B2), and perilla meal (B3C). Each protein was substituted for 23.0% of crude protein in TMR. Rumen digesta were taken through ruminal cannula at 1 h interval during the feeding cycle in order to analyze ruminal pH, ammonia-N, and volatile fatty acids (VFA). Plasma metabolites in blood taken via the jugular vein after the rumen digesta sampling were analyzed. Feeding perilla meal significantly (p < 0.05) decreased mean ruminal pH compared with control and the other protein feeding groups. Compared with control, feeding protein significantly (p < 0.05) increased ruminal ammonia-N concentration except for AB1. Statistically (p > 0.05) similar total VFA appeared among control and the supplemented groups. However, control, AB1, and B2 showed higher (p < 0.05) acetate concentrations than B3C, and propionate was vice versa. CNCPS fractionated protein significantly (p < 0.05) affected concentrations of albumin and total protein in blood; i.e. plasma albumin was lower for control and B2 groups than AB1 and B3C groups. Despite lack of significances (p > 0.05) in creatinine and blood urea nitrogen, AB1 and B2 groups were numerically higher than the others.","PeriodicalId":17916,"journal":{"name":"Korean Journal of Agricultural Science","volume":"27 1","pages":"392-399"},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76048325","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
H. Rhee, Sung-Min Choi, Joon-Woo Lee, Hyeongkeun Kweon
{"title":"Comparison of forest road status and policies between Korea and United States","authors":"H. Rhee, Sung-Min Choi, Joon-Woo Lee, Hyeongkeun Kweon","doi":"10.7744/KJOAS.20170040","DOIUrl":"https://doi.org/10.7744/KJOAS.20170040","url":null,"abstract":"Forest roads are essential for forest resource management. This study investigated and compared forest road and road policy data in Korea and the United States to improve future forest road policies in Korea. As compared to the United States (9.5 m/ha), Korea has much lower forest road density (3.19 m/ha) and has been actively constructing new forest roads. The Korea Forest Service leads forest road policy in Korea by providing subsidies for new road construction in non-national forests. The budget for forest roads accounted for 9.1% of the total Korea Forest Service budget in 2010 2015 and 73.5% of it was used for new road construction. Korean forest road policies have been distinctively changed over the past decades; e.g., an increase in forest road mileage in the 1990s, an increase in forest road standards in the 2000s, and an increase in the mileage of higher standard roads in the 2010s. In comparison to Korea, the United States has focused on road maintenance and road decommissioning since 2001. The budget for forest roads accounted for 2.9% of the total USDA Forest Service budget in 2011 2016 and 82.2% of it was used for operations and maintenance. Our study results suggest that forest road policies in Korea should start focusing on road maintenance and decommissioning, if needed.","PeriodicalId":17916,"journal":{"name":"Korean Journal of Agricultural Science","volume":"7 1","pages":"504-512"},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82930091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Value of clay as a supplement to swine diets","authors":"M. Daye, Jongmoon Lee, J. Choe, B. Kim, 오상남, 송민호","doi":"10.7744/kjoas.20170017","DOIUrl":"https://doi.org/10.7744/kjoas.20170017","url":null,"abstract":"The use of practical management factors to maximize pig health improvement cannot guarantee freedom from diseases. Moreover, because of health safety concerns, the use of antibiotics has been restricted in livestock, including pigs. Therefore, the swine industry has been looking for various alternatives to antibiotics to improve pig’s health and performance. Clay is a dietary factor generally accepted for improving pig health. It is a naturally occurring material and is primarily composed of fine-grained minerals. It has a specific structure with polar attraction. Because of this structure, clay has the ability to lose or gain water reversibly. In addition, clay has beneficial physiological activities. First, clay has anti-diarrheic and antibacterial effects by penetrating the cell wall of bacteria or inhibiting their metabolism. Second, it can protect the intestinal tract by absorbing toxins, bacteria, or even viruses. When added to the diet, clay has also been known to bind some mycotoxins, which are toxic secondary metabolites produced by fungi, namely in cereal grains. Those beneficial effects of clay can improve pigs’ health and performance by reducing pathogenic bacteria, especially pathogenic Escherichia coli, in the intestinal tract. Therefore, it is suggested that clay has a remarkable potential as an antibiotics alternative.","PeriodicalId":17916,"journal":{"name":"Korean Journal of Agricultural Science","volume":"100 1","pages":"181-187"},"PeriodicalIF":0.0,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80681470","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}