• Korean Journal of Agricultural Science
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• v.49 no.1
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• pp.113-120
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• 2022

Leaf blight disease caused by Stemphylium species is an important disease in Allium crops, specifically onion, garlic and welsh onion. In 2018, leaf blight symptoms were severe and damaged onion and garlic in Jeonnam province in Korea. In addition, small purple spots on garlic burbs were observed in a post-harvest storage warehouse. Several Stemphylium isolates were isolated from diseased leaves from the field and from garlic bulb samples and were analyzed in terms of homology and the phylogenetic relationship based on the internal transcribed spacer region and calmodulin gene sequence. The results showed that among three Stemphylium species identified, S. vesicarium is most prevalent on onion and garlic. S. eturmiunum was for the first time identified as pathogenic to onion and garlic, whereas S. solani was found in welsh onion crops. Although these isolates grew well at the optimum temperature at 20 - 25℃, they could also grow at low temperatures of 10 - 15℃. A pathogenicity test was conducted using S. vesicarium and S. eturmiunum on onion and garlic respectively. These results showed that two Stemphylium species were highly virulent with cross pathogenicity in onion and garlic. The results of this study can support the biological characterization of Stemphylium species in Korea. Moreover, further research will need to develop fungicide application strategies for onion and garlic crops.

• Advanced Industrial SCIence
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• v.3 no.2
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• pp.17-22
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• 2024

Recently, as the ICT field has been used in various environments, it has become possible to analyze pests by crops, use robots when harvesting crops, and predict by big data by utilizing ICT technologies in a sustainable agricultural environment. However, in a sustainable agricultural environment, efforts to solve resource depletion, agricultural population decline, poverty increase, and environmental destruction are constantly being demanded. This paper proposes an artificial intelligence-based big data processing analysis method to reduce the production cost and increase the efficiency of crops based on a sustainable agricultural environment. The proposed technique strengthens the security and reliability of data by processing big data of crops combined with AI, and enables better decision-making and business value extraction. It can lead to innovative changes in various industries and fields and promote the development of data-oriented business models. During the experiment, the proposed technique gave an accurate answer to only a small amount of data, and at a farm site where it is difficult to tag the correct answer one by one, the performance similar to that of learning with a large amount of correct answer data (with an error rate within 0.05) was found.

• Korean Journal of Breeding Science
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• v.42 no.2
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• pp.157-162
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• 2010

This study was carried out to develop of macro-protocol and the biosafety guide for 'Nakdong', and 'Golden Rice' (genetically modified vitamin A rice) by large scale field trial of GM crops. Typically, when a new GM crop is created, breeders should conduct field test to make sure the GM crop is safe, and provide some information on GM crops for approval. A total of isolated 4,700 $m^2$ field for trial of GM crops were prepared, and 'Nakdong' and 'Golden rice' were cultivated by standard method of RDA (Rural Development Administration, Korea). Field studies indicated that the population densities of insect pests and natural enemies have no difference between two varieties. While insect pest density on 'Nakdong' was slightly higher than on Golden Rice, but natural enemy density on Golden Rice was a little higher. These results provided the insect diversity for risk assessment analysis of Golden Rice and suggested that the macro-protocol could be useful to detect GM plants.

• Journal of The Korean Society of Grassland and Forage Science
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• v.26 no.4
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• pp.249-256
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• 2006

The object of this experiment was to suggest the optimum autumn sown small forage crops as next forage crops harvested maize in Daejeon area. The field trials was conducted from 2002 to 2004 at Chungnam National University in order to evaluate the dry matter yield and qualities of the autumn sown small forage crops. The experiment was consisted of split plots (main plot : forage crops as rye, barley and wheat, and sub plot 4 harvest stages as boot, heading, milk and dough) design with three replications. The average DM yield for 2 years of rye was higher than that of other forage crops (p<0.01). As stages proceed, the DM yield tended to increase in all forage crops (p<0.01). In chemical composition, they had a difference on forage crops and stages. The crude protein (CP) was higher in barley (p<0.01), but fibrous contents such as NDF, ADF, cellulose and lignin were lower in wheat than in the other forage crops (p<0.01). In Daejeon area, although barley and wheat at milk and dough stages were observed with maximum yield and high quality as autumn sown forage crops, due to late harvesting periods, it is difficult to utilize them as previous forage crops seeded in maize. Based on the result mentioned above, it is concluded that rye harvested at boot to heading stages is the most suitable fur autumn sown small forage crops in Daejeon area. Meanwhile, in order to have the option of nutritional value in wheat and barley, they need to be supplied early maturing and high-yield variety of wheat and barley.

• Korean Journal of Weed Science
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• v.11 no.1
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• pp.50-59
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• 1991

Residual period and carry-over effect of some herbicides were determined using a bioassay method in six summer crops(potato, carrot, corn, water melon, soybean, and sesame). The effects were measured at regular time intervals after applying different rates of the herbicides. There were no great differences in residual period and carry-over injury between the soils and kinds of crops used. However, the residual period varied with the herbicides studied and the carry-over injury was dependent upon season and rate of the herbicide application, sampling depth of soil, and kind and seeding date of the test plant. When the residual herbicides were applied, the carry-over injury could be minimized by selecting tolernet crops, delaying seeding of the crops after application of the herbicides, and regulating the cultivation depth. Herbicides which showed no residual effect by the end of the cropping period(100-120 days for summer crops) and no carry-over effect were alachlor, trifluralin, ethalfluralin, metribuzin, and prometryn. When pendimethalin, metolachlor, linuron, methabenzthiazuron, and simazine were applied at the recommended rate or less, there was no carry -over injury at harvesting time. With doubling the recommended rate, however, the carry-over effect was found in sensitive crops. Napropamide applied at the rate of 300 g a.i./10 a brought about carry-over injury for Italian ryegrass and barley at 140 days in summer crops, whereas the injury was not found in Cruciferae (radish, Chinese cabbage). Nitralin applied at the rate of 150-300 g a.i./10a caused the carry-over injury for Italian ryegrass and barley at 140 days in summer crops. However, there was no injury for Cruciferae.

• Korean Journal of Weed Science
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• v.11 no.1
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• pp.32-49
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• 1991

Residual period and carry-over effect of some herbicides were determined using a bioassay method in five winter crops (chinese cabbage, radish, spinach, onion and garlic). The effects were measured at regular time intervals after applling different rates of the herbicides. There were no great differences in residual period and carry-over injury between the soils and kinds of crops used. However, the residual period varied with the herbicides studied and the carry-over injury was rate of the herbicide application, sampling depth of soil, and kind and seeding date of the test plant. When the residual herbicides were applied, the carry-over injury could be minimized by selecting tolerant crops, delaying seeding of the crops after application of the herbicides, and regulating the cultivation depth. Herbicides which showed no residual effect by the end of the cropping period (200-240 days for winter crops) and no carry-over effect were alachlor, trifluralin, ethalfluralin and prometryn. When pendimethalin, metolachlor, linuron and methabenthiazuron were applied at the recommended rate or less, there was no carry-over injury at harvesting time. With doubling the recommended rate, however, the carry-over effect was found in sensitive crops. Napropamide applied in winter crops at rate of 150-300g a.i./10a brought about carry-over injury for such Gramineae as Italian ryegrass, direct-seeded rice and barley, whereas the injury was not found in lowland-transplanted rice, Cruciferae, Cucurbitaceae and Solanaceae. Long residual herbicide nitralin applied at the rate of 75g a.i./10a caused the carry-over injury for Italian ryegrass, direct-seeded rice, baley and lowland-transplanted rice at 275 days in winter crops. In addition, a slight injury occurred in sesame, perilla and spinach, However, there was no injury for Cruciferae, Cucurbitaceae and Solanaceae.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.5
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• pp.887-894
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• 2011

To evaluate the effects of abiotic factors of paddy fields on greenhouse gases (GHGs) emissions from rice paddy fields, $CH_4$ emission amounts were investigated from rice paddy fields by different soil organic matter contents, paddy types, and agricultural climatic zone in Yeongnam area during 3 years. $CH_4$ emission amounts according to soil organic matter contents in paddy field were conducted at having different contents of 5 soil organic matters fields (23.6, 28.7, 31.0, 34.5, and $38.0g\;kg^{-1}$), The highest $CH_4$ emission amount was recorded in the highest soil organic matters plot of $38.0g\;kg^{-1}$. High correlation coefficient (r=$0.963^{**}$) was obtained between $CH_4$ emissions from paddy fields and their soil organic matter contents. According to paddy field types, $CH_4$ emission amounts were investigated at 4 different paddy fields as wet paddy, sandy paddy, immature paddy, and mature paddy. The highest $CH_4$ emissions was recorded in wet paddy (100%) and followed as immature paddy 64.0%, mature paddy 46.8%, and sandy paddy 23.8%, respectively. For the effects of temperature on $CH_4$ emissions from paddy fields, 4 agricultural climatic zones were investigated, which were Yeongnam inland zone (YIZ), eastern coast of central zone (ECZ), plain area of Yeongnam inland mountainous zone (PMZ), and mountainous area of Yeongnam inland mountainous zone (MMZ). The order of $CH_4$ emission amounts from paddy fields by agricultural climatic zone were YIZ (100%) > ECZ (94.6%) > PMZ (91.6%) > MMZ (78.9%). The regression equation between $CH_4$ emission amounts from paddy fields and average air temperature of Jul. to Sep. of agricultural climatic zone was y = 389.7x-4,287 (x means average temperature of Jul. to Sep. of agricultural climatic zone, $R^2=0.906^*$)

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.5
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• pp.529-539
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• 2010

In order to evaluate the effect of soil salinity and culturing conditions including compost application and vinyl mulching on the maintenance of ridge and the growth of upland crops, three crops such as corn, soybean and sweet potato were experimented by using three or four cultivars of crops in the Saemangeum reclaimed tidal land. Average soil salinity before seeding was 2 dS $m^{-1}$, which was low enough for general upland crops to grow. However, high soil EC more than 16 dS $m^{-1}$ was observed in some parts of the experimented field. In the experiment, it was concluded that growth retardation and yield reduction of summer upland crops might be from severe erosion of ridge, soil compaction, flooding or wet soil condition and high salinity of some parts, and then these deteriorations were possibly improved for good crop growth and yield increase by compost application and vinyl mulching cultivation in the Saemangeum reclaimed tidal land.

• Korean Journal of Plant Resources
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• v.35 no.5
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• pp.686-695
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• 2022

The grain yield and flour quality of winter wheat (Triticum aestivum L. 'Jokyung') were investigated in the paddy fields in which the double-cropping of wheat linked to rice (Oryza sativa L.) and its alternative crops [black soybean (Glycine max (L.) Merr.), sesame (Sesamum indicum L.), and perilla (Perilla frutescens (L.) Britton)] was applied. In the soils in which black soybean, sesame, and perilla as pre-crops were cultivated, the soil pH was higher and the electrical conductivity was lower than in the rice pre-cropped soil. In addition, the available phosphate (Av. P₂O₅), and contents of Ca²⁺ and Mg²⁺ were higher than in the rice pre-cropped soil. Winter wheat growth characteristics such as culm length, spike length, number of spikes and grains were generally favorable in the black soybean pre-cropped soil. However, the grain yield of winter wheat increased in the black soybean, sesame, and perilla pre-cropped soils by 100 kg/10a or more than in the rice pre-cropped soil. Furthermore, protein content and SDS-sedimentation value of the flour were higher, while amylose content was slightly lower, in the black soybean, sesame, and perilla pre-cropped soils than in rice pre-cropped soil. These results suggest that cultivation of rice alternative crops such as sesame, black soybean, and perilla as pre-crops in paddy soil could improve the physical and chemical properties of the soil and contribute to producing high-quality wheat flour more advantageous for the baking process.

• Korean Journal of Environmental Agriculture
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• v.32 no.4
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• pp.323-331
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• 2013

BACKGROUND: Liquid pig manure(LPM) is a useful resource if it is sufficiently fermented and utilized in the agriculture; it provides nutrients to soils, circulates organic materials and replaces chemical fertilizers(CF) with reasonable costs. Currently, there are not many trials in paddy field to continuously cultivate the crops in winter and summer season using LPM. METHODS AND RESULTS: When cultivating winter forage crops (Whole-crop-barley(WCB), Rye, Triticale, Italian ryegrass(IRG)) and summer feed corns in the rice field, CF was treated with $N-P_2O_5-K_2O$(winter forage crops: 120-100-100kg/ha, summer feed corn: 200-150-150 kg/ha), and subsequently, growth, yields, feed values and chemical properties of soil were investigated. LPM-applied areas in both winter and summer forage crops showed higher plant lengths and tillers than those of CF-applied areas, but the yield in CF-applied areas was higher than that of LPM-applied areas under continuous application of 2 years. Crude protein, neutral detergent fiber(NDF), acid detergent fiber(ADF) and total digestion nutrient(TDN) in feed values showed almost similar results between LPM and CF-applied areas. EC, organic matter, available phosphate and exchangeable cations of soils after the experiment increased in LPM applied areas, and especially, the contents of available phosphate and exchangeable sodium were high. CONCLUSION(S): Considering the above results, it was concluded that if LPM are properly utilized for continuous winter and summer cultivation of feed crops at paddy field, the cultivation costs could be decreased and be helpful to the stable production of domestic feeds.