• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.1 no.1
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• pp.22-30
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• 2020

Many areas of vegetation in the British uplands have reduced species diversity as a result of sheep overgrazing. It has been suggested that abandonment or re-wilding strategies might be used to reverse this. A likely first step would be the removal or reduction of grazing livestock from upland areas, with a presumption that this would lead to a recovery in species richness. However, we do not know if this would work, or the timescales involved. One of the important areas where more knowledge is needed is information on the size and composition of soil seedbanks as regeneration from zseed is a likely pathway of recovery. Here, we compared seedbanks in both grazed and ungrazed plots in five experiments at Moor House NNR in the northern Pennines; these sheep grazing exclusion experiments were started 52 and 63/64 years ago. Soil samples (n=10) were collected from both grazed and ungrazed plots in each experiment, and seed emergence counted in glasshouse trials. We detected only seeds of common species and very few dicotyledonous species. This suggests that the soil seedbank is unlikely to be a reliable source of the less common species for ecological restoration in these upland communities, suggesting an extinction debt. Therefore, seed addition and the creation of suitable safe-sites for germination may be needed in conjunction with grazing controls to allow the establishment of plants that will increase the species richness of the vegetation. However, this interventionist restoration approach remains to be tested.

• Korean Journal of Agricultural Science
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• v.44 no.3
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• pp.359-365
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• 2017

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 $400^{\circ}C$ 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 $90t\;ha^{-1}$, 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 $90t\;ha^{-1}$. Compared with the control (i.e., no biochar), biochar application increased soil pH and electrical conductivity (EC). Addition of biochar (54 and $90t\;ha^{-1}$) 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.

• Korean journal of applied entomology
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• v.37 no.2
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• pp.117-121
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• 1998

This experiment was conducted to investigate host preference, occurrence and intraplant distribution of Trialeurodes vaporariorum (Westwood) and Encarsia formosa (Gahan) in greenhouse. T vaporariorum preferred cucumber over tomamto. 7: vaporariorum adults distributed at upper part of cucumber plant. Nymphs also distributed at upper part in early growing stage of cucumber but became to distribute lower part after 40 days. E. formosa adults were found mainly at mid-upper part of plant but there was no significant difference in statistics all analysis among each parts and also mummy distributed mid-low part. E. formosa were released when five ir: vaporariorum were caught by yellow sticky trap per week in glasshouse. The treatment of one tag (50 mummies) of E. formosa per five plants controlled successfully the 7: vaporariorum population after 40 days.

• Journal of The Korean Society of Agricultural Engineers
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• v.54 no.3
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• pp.113-124
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• 2012

Reliable estimation of energy load inside the greenhouse and the selection of cooling and heating facilities are very important preceding factors to save energy as well as initial and maintenance costs of operating a greenhouse. Recently, building energy simulation (BES) technique to simulate a model similar to the actual conditions through a variety of dynamic simulation methods, and predict and analyze the flow of energy is being actively introduced and developed. As a fundamental research to apply the BES technique which is mainly used for analysis of general buildings, to greenhouse, this research designed four types of naturally-ventilated greenhouses using one of commercial programs, TRNSYS, and then compared and analyzed their energy load properties, by applying meteorological data collected from six regions in Korea. When comparing the greenhouse load of each region depending on latitude and topographical characteristics through simulation, Chuncheon had nearly 9~49 % higher heating load per year than other regions, but its annual cooling load was the reverse to it. Except for Jeju, 1-2W type greenhouses in five regions showed about 17 % higher heating load than a widespan type greenhouse, and 1-2W type greenhouses in Chuncheon, Suwon, Cheongju, Daegu, Cheonju and Jeju had 23 %, 20 %, 17 %, 16 %, 18 % and 20 % higher cooling load respectively than a wide span-type one. Glasshouse and vinyl greenhouse showed 8~11 % and 10~12 % differences respectively in heating load, while 2~10 % and 7~10 % differences in cooling load respectively.

• The Plant Pathology Journal
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• v.36 no.3
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• pp.218-230
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• 2020

Net blotch of barley caused by Pyrenophora teres (Died.) Drechsler, is one of the most destructive diseases on barley in Algeria. It occurs in two forms: P. teres f. teres and P. teres f. maculata. A total of 212 isolates, obtained from 58 fields sampled in several barley growing areas, were assessed for fungicide sensitivity by target gene analysis. F129L and G137R mitochondrial cytochrome b substitution associated with quinone outside inhibitors (QoIs) resistance, and succinate dehydrogenase inhibitors (SDHIs) related mutations (B-H277, C-N75S, C-G79R, C-H134R, and C-S135R), were analyzed by pyrosequencing. In vitro sensitivity of 45 isolates, towards six fungicides belonging to three chemical groups (QoI, demethylase inhibitor, and SDHI) was tested by microtiter technique. Additionally, sensitivity towards three fungicides (azoxystrobin, fluxapyroxad, and epoxiconazole) was assessed in planta under glasshouse conditions. All tested isolates were QoI-sensitive and SDHI-sensitive, no mutation that confers resistance was identified. EC₅₀ values showed that pyraclostrobin and azoxystrobin are the most efficient fungicides in vitro, whereas fluxapyroxad displayed the best disease inhibition in planta (81% inhibition at 1/9 of the full dose). The EC₅₀ values recorded for each form of net blotch showed no significant difference in efficiency of QoI treatments and propiconazole on each form. However, in the case of fluxapyroxad, epoxiconazole and tebuconazole treatments, analysis showed significant differences in their efficiency. To our knowledge, this study is the first investigation related to mutations associated to QoI and SDHI fungicide resistance in Algerian P. teres population, as well as it is the first evaluation of the sensitivity of P. teres population towards these six fungicides.

• Horticultural Science & Technology
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• v.33 no.1
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• pp.11-17
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• 2015

The study was conducted to investigate the effect of rootstock on growth and early yield of stenting-propagated cut roses (Rosa hybrida Hort.) 'Pink Aurora' and 'Yellow King'. The scions, prepared as single-node cuttings, each with a five-leaflet leaf, were grafted onto cuttings of Rosa indica 'Major', Rosa multiflora 'Chille Wonye No. 1', Rosa multiflora 'K-1', or Rosa multiflora 'Burr' as the rootstock. The rootstock cuttings were removed of all leaves and buds before grafting. The base of scion and the top of rootstock were held together and simultaneously cut at a $45^{\circ}$ angle for ease of grafting. Scion-rootstock unions were stuck in rockwool cubes and placed on a misted glasshouse bench for rooting before being transplanted into a rockwool slabs for cultivation. Rooting was the greatest in the 'Pink Aurora' and 'Yellow King' grafted on the rootstock Rosa indica 'Major'. In 'Pink Aurora', stem length, stem diameter, five-leaflet leaves per stem, and stem fresh weight of the harvested cut flowers were not affected by the rootstock. The greatest total yield of 'Pink Aurora' was obtained in plants grafted onto the Rosa indica 'Major' rootstock. Overall growth of 'Yellow King' was the greatest in plants grafted onto Rosa multiflora 'Burr' rootstock, although total yield was not affected by the rootstock. These results suggest that Rosa indica 'Major' is the most effective rootstock not only for rooting, but also for early yield and growth for stenting propagation of these cut roses.

• Horticultural Science & Technology
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• v.33 no.1
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• pp.133-142
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• 2015

This study aimed to identify the exercise intensity associated with four common physical activities for adults (running, skipping rope, walking, and muscle strength exercises) and two horticultural activities (creating a vegetable bed and garden maintenance). For this experiment, 19 males (mean age: $25.8{\pm}2.3$ years) randomly participated in the activities at a glasshouse at Konkuk University. Each of the six activities lasted for 5 minutes; the subjects rested for 5 minutes during intervals between the activities. A portable metabolic analyzer was used to store the oxygen and energy consumption values obtained upon measurement of each activity. In addition, a wireless heart rate monitor was used to measure the subjects' heart rate. According to the results, the four types of physical activities and two horticultural activities carried out by the subjects are moderate- to high-intensity activities [i.e., $3.8{\pm}0.9$ to $9.9{\pm}2.1$ metabolic equivalents (METs)]. Running ($9.9{\pm}2.1$ METs) and skipping rope ($8.8{\pm}2.2$ METs) were categorized as high-intensity physical activities, whereas creating a vegetable bed ($5.0{\pm}1.2$ METs), walking ($4.9{\pm}0.8$ METs), muscle strength exercises ($4.5{\pm}1.3$ METs), and garden maintenance ($3.8{\pm}0.9$ METs) were classified as moderate-intensity physical activities. The exercise intensities of horticultural activities in this study were similar to those of walking and muscle strength exercises. Therefore, participating in these horticultural activities is expected to garner health benefits similar to those reaped from the physical activities described in the current study.

• Korean Journal of Agricultural Science
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• v.50 no.2
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• pp.231-239
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• 2023

Ammonia (NH₃) emitted from the use of fertilizers during agricultural practice generates particulate matter and odors. The application of carbonized rice husk, an eco-friendly material, is one of the measures used to reduce NH₃. The objective of this study was to evaluate the effect of the application rate and pH of carbonized rice husk on NH₃ emissions and soil quality. An experiment to assess NH₃ emissions was performed in a glasshouse using a static chamber method. The pH of the carbonized rice husk was divided into acidic, neutral, and basic groups, and the carbonized rice husk application rates were 1, 3, and 5% of the soil weight. NH₃ emissions showed a sharp increase within three days after the inorganic fertilizer was applied. Subsequently, NH₃ emissions decreased rapidly after basal fertilization compared to primary and secondary top-dressing. When carbonized rice husks were applied to soil, NH₃ emissions decreased in all treatments, and neutral carbonized rice husk was the most effective in comparison with acidic and basic carbonized rice husk. The application rate of carbonized rice husk and NH₃ emissions showed a negative correlation, and the lowest emissions were found in units with a 5% application rate. Also, there was no statistically significant difference between NH₃ emissions according to the application rate of carbonized rice husk, and when carbonized rice husks were applied at a 5% rate, soil OM increased excessively. Therefore, it is recommended to apply only 1% neutral carbonized rice husk to most effectively reduce NH₃ emissions in the soil.

• Journal of Bio-Environment Control
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• v.8 no.2
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• pp.75-82
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• 1999

This study was carried out to examine the effect of day/nignt temperatures during seedling culture on the vegetative and reproductive growth of Lycopersicum esculentum ‘Seokwang’. The study was consisted of two culture stages, plug seedling production in the growth chamber and hydroponic culture of the plant in a glasshouse. Experiments were replicated over time. The germinated seedlings were raised for 33 days (experiment 1) and 35 days (experiment 2) in 4 growth chambers, each with day/night temperatures of either $25^{\circ}C$/$25^{\circ}C$, 16$^{\circ}C$/16$^{\circ}C$, 16$^{\circ}C$/$25^{\circ}C$ or $25^{\circ}C$/16$^{\circ}C$. Cool-white fluorescent lamps provided 140$\mu$mol.m$^{-2}$ .s$^{-1}$ light for 12h each day. In the second experiment, all chambers were supplied with 1000$\mu$mol.mol$^{-1}$ CO$_{2}$ during the photoperiod and had an air velocity of 0.3m.s$^{-1}$ and relative humidity of 80%. Plug seedlings raised were transplanted to rockwool slabs in a glasshouse and were grown hydroponically using the same nutrient solutions used for seedling culture for 37 days (experiment 1) and 35 days (experiment 2). Plant height was affected more by mean daily temperature than by interaction of day and night temperatures. Plant height was the highest in 16/16$^{\circ}C$ treatment. Leaf count was not affected by day and night temperatures, and the chlorophyll concentration was the highest in 16/$25^{\circ}C$ treatment. Fresh and dry weights of stem tended to be greater in treatments of constant day and night temperature. The number of node on which first and second flower clusters were set was significantly higher in 25/$25^{\circ}C$ treatment than in the other treatments. Days to flower of the first flower on the first flower cluster were the greatest in 25/$25^{\circ}C$ and the least in 16/$25^{\circ}C$ treatment. Vegetative and reproductive growth, such as height, fresh and dry weights, days to flower, and nodes of the 1st and 2nd flower cluster set were affected by day/night temperatures.

• Journal of Bio-Environment Control
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• v.18 no.3
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• pp.244-252
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• 2009

This research aims at comparison of climatic conditions of sweet pepper's greenhouse between Korea (KOR) and the Netherlands (NL) to find out the reason of much lower yield in KOR than NL focus-ing on greenhouse climatic conditions. Hence, greenhouse climate data were obtained from each one commercial glasshouse in both countries. The crops (cv. 'Derby') were grown on rockwool slab with two stems per plant with 3.75plants/$m^2$ in KOR and three stems per plant with 2.5plants/$m^2$ or four stems per plant with 1.875plants/$m^2$ in NL. Even though plant density was differed but stem density was on the same to 7.5stems/$m^2$. There was no significantly difference on weekly growth of sweet pepper plant both countries, whereas harvested nodes to whole nodes of NL's plant was more than two times higher compared to KOR. The averaged daily global radiation during the whole growing periods was 14.5MJ/$m^2$/day in KOR and l2.1MJ/$m^2$/day in NL. Averaged 24h temperature was similar to both glasshouse as $21.6^{\circ}C$ in KOR and $21.2^{\circ}C$ in NL during the whole growing periods, however the variance was higher in KOR than NL. Humidity deficit (HD) was observed higher in KOR during the whole growing periods. Averaged day $CO_2$ concentration was measured contrary pattern in both countries because of heating to greenhouse on NL winter season. Averaged 24h temperature and day $CO_2$ concentration to daily global radiation was regular pattern in NL, whereas there are large scatter in KOR. Consequently, more irregular greenhouse climate condition in KOR could be induced irregularly crop growth.