• Research in Plant Disease
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• v.24 no.2
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• pp.87-98
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• 2018

The fungal species contain diverse transposable elements and repetitive sequences up to ~10% of their genome. It has been reported that distribution of transposable elements tends to correlate with the host range of the pathogen. Moreover, transposable elements cause the loss of an avirulence gene in the pathogen, which resulted in disease on a resistance cultivar. Thus, the transposable elements in the fungal pathogens may be one of the key factors driving the plant-fungus interactive evolution. In this article, we reviewed classification and biological functions of transposable elements in Magnaporthe species.

• Korean Journal of Soil Science and Fertilizer
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• v.16 no.1
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• pp.50-55
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• 1983

Effects of nitrogen applied to grown alone and in mixture with grass and legumes of forage crops on the yield of dry matter, absorptivity, and the amount of nitrogen fixation were studied using $^{15}N$ ammonium sulfate. 1. The amount of nitrogen fixation in legume was decreased in order of alfalfa > red clover > birdsfoot trefoil, and red clover gave highest soil-nitrogen dependency. 2. Fertilizer nitrogen for the yield of dry matter was highly effective only in orchardgrass, and effective at the early stages of alfalfa and birdsfoot trefoil in case of a mixed sowing. 3. Alone and mixed sewings showed the yield of dry matter in decreasing order of alfalfa > red clover > orchardgrass > birdsfoot trefoil and orchardgrass + alfalfa > orchardgrass + red clover > orchardgrass + birdsfoot trefoil, respectively. 4. The plot of with nitrogen showed greater nitrogen uptake than the plot of without-nitrogen throughout the plots. In case of grown alone, however, difference in the absorptivity of various forage crops was decreased in order of alfalfa > red clover > orchardgrass > birdsfoot trefoil. 5. Regardless of nitrogen application, nitrogen uptake amount of orchardgrass was higher in the plot of mixture then in the plot grown alone, except the with nitrogen plot of red clover grown in mixture at the ratio of 3 : 7.

• Korean journal of applied entomology
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• v.55 no.4
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• pp.389-403
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• 2016

Sugar beet nematode (Heterodera schachtii Schmidt) was first detected in 2011, in Chinese cabbage grown in the highland areas of Korea. Chemical control of the nematode by nematicides is not feasible due to its cyst-forming characteristics; therefore, the cultivation of non-host crops is a preferable alternative to utilize nematode-infected fields. In this study, a total of 276 plant cultivars belonging to 18 different families were screened to evaluate their resistance to the nematode. Based on the number of cysts formed following nematode inoculation, the tested crops were classified into 3 levels: susceptible, moderately susceptible, and resistant/immune. Among the 276 cultivars tested, 106 cultivars were susceptible, 40 cultivars were moderately susceptible, and 130 cultivars were resistant/immune. Among the resistant/immune cultivars, cyst formation was not observed on eggplant, tomato, lettuce, perilla, carrot, celery, watermelon, oriental melon, cucumber, pumpkin, chives, onion, welsh onion, balloon flower roots, deodeok (Codonopsis lanceolata), Jandae (Adenophora triphylla), and bean. Therefore, these plants are regarded as immune to the cyst nematode. However, many crops belonging to Solanaceae, Asteraceae, Chenopodiaceae, and Poaceae families showed moderate susceptibility or immunity, depending on the crop or cultivar. This study provides a basis for alternative crop recommendations for sugar beet nematode cyst-infected farms in Chinese cabbage production areas.

• Microbiology and Biotechnology Letters
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• v.1 no.1
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• pp.31-36
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• 1973

A method for acid-hydrolysis of agricultural wastes and its utilization was investigated. In order to obtain fermentable sugar solution from cellulosic wastes such as cereal straws and hulls, in particular, of rice, barley and wheat, the chemical compositions were analyzed and optimum conditions of hydrolysis determined. The cereal straws contain 42 to 55 % of crude cellulose including hemicellulose. On the hydrolysis with 1% of sulfuric acid at 40 psig, 35.6% of the reducing sugar based on the weight of dry matter was formed from rice straw, (variety Chinheung) in 30 min. More powerful condition of hydrolysis would appear to decompose the sugar formed into other compounds, for instance, furfural. Under atmospheric pressure with 5% of the acid, rice straw was hydrolyzed to 35% of reducing sugar content in 3 hours. Candida utilis could assimilate the sugars in the hydrolyzate up to more than 97%, and a yield of the yeast cells reached 55% to the utilized sugars.

• Journal of The Korean Society of Grassland and Forage Science
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• v.5 no.1
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• pp.53-61
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• 1985

Effects of nitrogen incorporated with 15N-nitrogen, which was applied to grown alone and in mixture with grass and legumes of forage crops, on the yield of dry matter, total nitrogen content, percentage of nitrogen derived from fertilizer (P.N.D.F.), A-value were studied, and the results obtained are as follows: 1. With nitrogen for the yield of dry matter was highly effective only to orchardgrass and were also effect to the early stages of alfalfa and birdsfoot trefoil in case of a mixed sowing. 2. Alone and mixed sowings showed the yield of dry matter in decreasing order of alfalfa<red clover>orchardgrass>birdsfoot trefoil, and orchardgrass + alfalfa>orchardgrass + red clover>orchardgrass + birdsfoot trefoil, respectively. 3. In case of grown alone, orchardgrass gave higher percentage of nitrogen derived from fertilizer (P.N.D.F.) than legume, whereas in case of grown in mixture it was in reverse order throughout the plots. It appears likely that orchardgrass was rather supplied soil nitrogen by legume then by nitrogen application. And P.N.D.F. was getting smaller in the latter stage of all forage crops in case of grown alone. In case of grown in mixture, however, and inconsistent P.N.D.F. was obtained from orchardgrass. 4. The A-value in case of grown alone was decreased in order of alfalfa>red clover>orchardgrass>birdsfoot trefoil. In contrast, however, the A-value in case of grown in mixture wes decreased in order of orchardgasss+alfalfa (3:7)>orchardgrass+red clover (3:7)>orchardgrass+red clover (3:7)>orchardgrass+alfalfa(5:5)>orchardgrass+birdsfoot trefoil (5:5)>orchardgrass+red clover (5:5)>orchardgrass+birdsfoot trefoil (3:7).

• Korean Journal of Soil Science and Fertilizer
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• v.45 no.5
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• pp.779-786
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• 2012

Many farmers have been seeking alternatives to chemical fertilizer for successful organic fruit production. This experiment was carried out to investigate the replaceability of chemical fertilizer by cover crop and slurry composting biofiltration (SCB) liquid manure (LM) application in pear orchard. Three treatments were contained in this experiment; cover crop only and cover crop + LM treatment, and control (chemical fertilizer application). Dry weight and mineral contents of gramineous cover crops were significantly increased in LM-combined treatments than that of leguminous species. Bulk density of soil was decreased in rye + LM and hairy vetch + LM treatments, compared with each cover crop treatment. Soil pH was lowest in fertilizer treatment and soil nitrate content became similar between treatments after rainy season. Available soil phosphate was lower in cover crop and cover crop + LM treatmemts than control, but exchangeable Mg was higher. The mineral content and net assimilation rate of leaves showed no difference between the treatments. As a result, it is suggested that the application of SCB liquid manure in pear orchard managed by cover crops is desirable to maintain the productivity by improving soil physical properties and potential nutrient recovery.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.4
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• pp.247-253
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• 2008

Winter annual green manure crops may be an effective tool for environmental-friendly agriculture system. The effect of legume (hairy vetch), non-legume (rye) and N fertilization ($190kg\;N\;ha^{-1}$) was examined and compared on red-pepper yield, nitrogen uptake, carbohydrate composition, and soil N and C contents. We monitored soil N and C for 120 days after incorporation (DAI) of green manures or mineral fertilizer. The mineralization of nitrogen reached the maximum around 30 DAI. The amount of inorganic nitrogen supplied by mineralization of hairy vetch residue was greater with than chemical N or rye. Photosynthetic rate was similar by 70 DAT in all treatments however, it in rye-incorporated red-pepper presented a sharp decline at later growth period. Leaf total nitrogen was greater with hairy vetch and chemical N than rye throughout the experiment. The soluble sugar increased steadily in all treatments from 40 to 110 days after transplanting (DAT) whereas starch showed a tendency of great decrease. Hairy vetch greatly promoted red-pepper growth by the later period however, chemical N showed the highest fruit yields.

• Korean Journal of Agricultural Science
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• v.33 no.2
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• pp.123-127
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• 2006

This study was carried out to compare growth and yield performance for soil conditions at the Maize Genetics and Breeding Lab. in Chungnam National University. The waxy hybrid corn in the drained soil of paddy field showed higher fresh yield per 10a and 100-kernel weight per plant than control. The average dry yield of drained and drainless soil were 804kg/10a and 498kg/10a compared with a control (751kg/10a), respectively. The waxy hybrid corn in the drained soil also had better good stand and stay green characteristics than drainless soil condition, and showed moderately resistance to water stress and weed. Vegetational feature of weeds was characterized as the prevalence of Acalypha auatralis, Echinochloa crus-galli, Persicaria hydrpopiper in drained paddy soil and Persicaria hydrpopiper, Acalypha auatralis, Echinochloa crus-galli in drainless paddy soil, and Echinochloa crus-galli, Acalypha auatralis in upland soil.

• Korean Journal of Organic Agriculture
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• v.19 no.2
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• pp.255-272
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• 2011

This work studied the growth and yield of green crops, changes of mineral composition in greenhouse soil and green crops, and infection with wintering green crops cultivation in greenhouse field. At 74 days after seeding of wintering green crops, dry matter was 710kg/10a in rye, 530kg/10a in barley, 230kg/10a in hairy vetch, and 240kg/10a in bean or weeds. Total nitrogen content in green crops was 4.5% in pea and hairy vetch, and 3~4% in barley and rye. $P_2O_5$, CaO, and MgO contents in all green crops were about 1.0%, and $K_2O$ content was the highest level by 4~5% among macro elements. Total nitrogen fixing content in shoot green crops uptaken from soil was 22.1kg/10a in rye, 20.6kg/10a in barley, 10.6kg/10a in hairy vetch, and 9.6kg/10a in pea and giant chickweed. $P_2O_5$ fixing content in shoot green crops uptaken from soil was 8.4kg/10a in rye, 6.3kg/10a in barley, and 2.3 kg/10a in hairy vetch and pea. $K_2O$ fixing content in shoot green crops uptaken from soil was 28kg/10a in rye, 24.7kg/10a in barley, and 11kg/10a in hairy vetch and pea. CaO fixing content in shoot green crops uptaken from soil was 2~3kg/ 10a in all green crops, and MgO fixing content was 1.7~2.6kg/10a in all green crops. Pepper growth in no-tillage was not a significant difference at all green manure crops. The number of fruit and fruit weight were higher in control, pea, hairy vetch and harvest barley than rye and barley. Soil mineral compositions in wintering green crops increased at pH, organic matter, CEC compared with control. Soil chemical compositions were stable level at green crops cultivation according as decreases of EC, available phosphoric acid, Ca, and Mg contents. After no-tillage by green manure crops, pH in soils was higher in green manure crops than control. EC content in soils was lower in green manure crops than control, and was remarkably low level in barley harvest. Organic matter content in soils increased in hairy vetch and barley green manure but decreased by 35% in barley harvest. Total nitrogen and avaliable $P_2O_4$ content in soils remarkably increased but was not a significant difference at all green manure crops. Cation (K, Ca, and Mg) content in soils decreased by 15~20% in K, 2~11% in Ca, and 3~6% in Mg at rye, barley and pea compared with control.

• 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.