• KOREAN JOURNAL OF CROP SCIENCE
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• v.54 no.2
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• pp.210-217
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• 2009

Pollen flow is one of the essential components in the ecological risk assessment of transgenic crops, because pollen can act as a vehicle to disseminate transferred alien genes. Pollen flow pattern of a cultivated rice variety and Living modified (LM) rice was studied at diurnal and distance changes under field. We measured airborne pollen density at the distances of -1, 0.5, 0, 1, 2, 3, 4, 5, 7, 9, 11 and 13 m from rice cultivation and recorded the direction and speed of wind using weather station in the conventional rice paddy field during the flowering period of rice. Diurnal changes in pollen density were observed as a peak between 10:00 to 13:00 hr. The density of airborne rice pollen geometrically decreased with the increase of distance from pollen sources. It is therefore necessary to carry out a detailed investigation of pollen flow of a particular species, where ecological risk assessment requires an accurate estimation of pollen flow including both distance and intensity of pollen dispersal. The rice pollen flow was significantly influenced by weather conditions, particularly by wind direction and speed. The precise determination of the local wind conditions at flowering time therefore appears to be of primary importance for setting up suitable isolation distance from transgenic rice in the field.

• Journal of Korean Society of Forest Science
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• v.102 no.1
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• pp.136-142
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• 2013

Optimal condition for pollen germination was suggested as a basic research of flowering physiology in order to identify the characteristics of flowering and seed setting of rare and endangered Forsythia saxatilis Nakai. Pollen samples were collected during flowering time from the end of March to the beginning of April. First, a suitable germination temperature, medium sucrose concentration and germination time were determined for pollen germination and pollen tube elongation in vitro, and then an optimal pH of culture medium. Pollen germination and tube elongation were significantly different among the levels of germination temperature, sucrose concentration and germination time. Interactive effects were observed between germination temperature and time, germination temperature and sucrose concentration, germination time and sucrose concentration. Pollen germination was the highest at $10^{\circ}C$ and increased with the increase of sucrose concentration, whereas it had no relation with germination time. In addition, pollen germination and tube elongation did not increase at more than 15% of sucrose concentration and 24 hours later. Pollen germination was the highest at pH 5 (20.8%) and the lowest at pH 6 (3.8%). In conclusion, $10^{\circ}C$, 15% sucrose and pH 5 were proposed as the optimal condition for pollen germination 24 hours later of pollen culture.

• Atmosphere
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• v.25 no.2
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• pp.221-233
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• 2015

Pollen is closely related to health issues such as allergenic rhinitis and asthma as well as intensifying atopic syndrome. Information on current and future spatio-temporal distribution of allergenic pollen is needed to address such issues. In this study, the Community Multiscale Air Quality Modeling (CMAQ) was utilized as a base modeling system to forecast pollen dispersal from oak trees. Pollen emission is one of the most important parts in the dispersal modeling system. Areal emission factor was determined from gridded areal fraction of oak trees, which was produced by the analysis of the tree type maps (1:5000) obtained from the Korea Forest Service. Daily total pollen production was estimated by a robust multiple regression model of weather conditions and pollen concentration. Hourly emission factor was determined from wind speed and friction velocity. Hourly pollen emission was then calculated by multiplying areal emission factor, daily total pollen production, and hourly emission factor. Forecast data from the KMA UM LDAPS (Korea Meteorological Administration Unified Model Local Data Assimilation and Prediction System) was utilized as input. For the verification of the model, daily observed pollen concentration from 12 sites in Korea during the pollen season of 2014. Although the model showed a tendency of over-estimation in terms of the seasonal and daily mean concentrations, overall concentration was similar to the observation. Comparison at the hourly output showed distinctive delay of the peak hours by the model at the 'Pocheon' site. It was speculated that the constant release of hourly number of pollen in the modeling framework caused the delay.

• Horticultural Science & Technology
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• v.28 no.6
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• pp.942-947
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• 2010

In the present study, pollen tube growth and fruit set in Asian pear ($Pyrus$ $pyrifolia$) were examined upon the mechanical damage on the stigma and style following the artificial pollination. When the upper middle part of style was cut off at 48 h after the artificial pollination, pollen tube grew to the middle of the style and the subsequent pollen tube elongation and fruit set normally occurred. When the style was cut off before the pollen tube reached the middle of the style, however, no pollen tube elongation and fruit set occurred. With the pollen tube elongation through the style, callose plugs at the basal part of the pollen tube were formed to the direction of the elongation at regular intervals. When the upper part of pollen tube attached pollen grain was cut off, however, callose plugs were formed defectively in the pollen tube, and the pollen tube opened and lost their turgor pressure. These facts might be the reason for the ceased or delayed pollen tube elongation and ultimately the failure of the fertilization.

• The Korean Journal of Food And Nutrition
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• v.23 no.2
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• pp.212-217
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• 2010

To enhance the quality of traditional Dasik, pollen Dasik containing brown rice flour fortified with 5, 10, 15 and 20% pollen powder were prepared, and their physicochemical properties were evaluated. Pollen Dasik possessed higher amount of mineral such as K and Ca than brown rice Dasik. The L value of pollen Dasik decreased with increasing pollen powder compared to brown rice Dasik, while the b value of pollen Dasik was increased with increasing pollen powder compared to brown rice Dasik(p<0.05). Hardness of pollen Dasik decreased with increasing amounts of pollen compared to the brown rice Dasik(p<0.05). Sensory evaluation on pollen Dasik preparewd with over 10% pollen showed the highest sensery evaluation value in overall preference.

• FLOWER RESEARCH JOURNAL
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• v.18 no.1
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• pp.62-65
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• 2010

This study was carried out to estimate the size and exine pattern of pollen grains in seven species of the genus Lilium by using scanning electron microscope. Exine of pollen grains, which were all monad, took the prolate forms with a pollen aperture. However, there were various L/W ratio between length (L) and width (W) of pollen grains among selected Lilium species. The pollen of L. distichum was oblong shape which had the highest L/W ratio of 2.59. On the other hand, that of L. concolor var. partheneion was broadly elliptical shape close to circle which had the lowest L/W ratio of 1.82. The surface patterns of exine were reticulate in all Lilium species that have showed diverse forms in their lumina. Pollen length and width in L. lancifolium had the greatest value, 115.90 and $46.54{\mu}m$, respectively, in comparison with those of L. tsingtauense, 70.33 and $38.72{\mu}m$, respectively. Except L. distichum and L. leichtlinii var. maximowiczii which had a similar pollen length within standard errors, the others in Lilium species showed different sizes, respectively. Therefore, these results indicated that pollen length could be a better standard for the classification of Lilium species than exine surface patterns or pollen dissection area.

• Journal of The Geomorphological Association of Korea
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• v.24 no.3
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• pp.1-11
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• 2017

The pollen analysis on the deposits of the lower marine terrace I of the estimated paleoshoreline height of 18m was performed in order to estimate the formation age of this terrace developed at the Sanha-dong coast, Ulsan, southeastern coast of the Korean peninsula. The pollen assemblage of the peat layer of SH-1 pollen zone (Quercus-Ulmus/Zelkova zone), lying directly on the marine rounded pebble layer of this terrace, shows that the climatic environment of the deposition period of SH-1 pollen zone was almost similar to that of the Postglacial climatic optimum period, but slightly cooler than that of the late warm stage of Last Interglacial(MIS 5a) in the eastern coast of Korea. This heightens the possibility that the deposition period of the marine rounded pebble layer which was covered by the above SH-1 peat layer is the MIS 5e which has been estimated by a previous study of the sedimentary facies of this terrace deposits (Choi, 2016). The pollen assemblage of SH-2 pollen zone (Pinus-Quercus zone) shows that the climate of this period was almost similar to that of the late Postglacial, but slightly cooler than that of the period of SH-1 pollen zone. This means that the climate around the Sanha-dong was still warmer in the deposition period of the peat layer of SH-2 pollen zone. Thus, the peat layer of SH-2 pollen zone was considered to have been deposited during the period from the early regression stage of the MIS 5d which is the estimated final stage in the deposition period of the above peat layer of SH-1 pollen zone to any stage in which the warmer environment of MIS 5 has still lasted. The humic silt layer of SH-3 pollen zone (Pinus-Ulmus/Zelkova-Abies zone) is assumed to have been deposited during the interstadial of the Last Glacial (MIS 3).

• Journal of Environmental Health Sciences
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• v.46 no.6
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• pp.735-749
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• 2020

Objectives: The aim of this study was to investigate airborne pollen counts, inhalant allergen sensitization rate, and allergic disease prevalence among elementary school children in Ulsan, South Korea during 2012-2018. Methods: Burkard samplers for pollen were installed on rooftops in suburban and urban areas in Ulsan. A 24-hour sampling of airborne allergens was conducted six days/week from January 1, 2013 to November 31, 2018. Skin prick tests were done with a total of 4,246 primary school students residing in urban and suburban areas in 2012, 2014, 2016, and 2018. This study examined sensitization to 20 major inhalant allergens. Results: The highest monthly counts of airborne pollen were observed in April and September each year. Among the pollen identified over the six years, pine showed the highest pollen counts (44.3%), followed by oak (22.3%), alder (6.3%) and Japanese hops (4.3%). Tree pollen predominated from March to June, and weed pollen predominated from August to October. Higher sensitization rates for inhalant allergens were observed in Dermatophagoides farinae (42.4%), Dermatophagoides pteronyssinus (43.6%), cat fur (12.1%), birch (9.9%), oak (9.6%), and alder (8.7%). The inhalant allergen sensitization rate was highest in the group with comorbidity (asthma and/or rhinitis and atopic dermatitis), and respiratory allergic disease (asthma and/or rhinitis) was higher than that of atopic dermatitis. Conclusion: Both the counts of tree pollen in the air and the sensitization rate for tree pollen were high in Ulsan. The temporal change in respiratory allergic diseases was similar to that for the sensitization rate of tree pollen, such as oak. In the future, it is considered that additional continuous research on various inhalant allergens and pollen should be conducted.

• Journal of Korean Society of Forest Science
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• v.99 no.5
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• pp.663-672
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• 2010

The pollen morphology of eleven species and three forms of the genus Rhododendron (Ericaceae) in Korea was examined using light, scanning electron and transmission electron microscopy. The pollen grains are grouped in permanent tetrahedral tetrads; viscin threads are present on the tetrads. The hexacolporate tetrads are of tricolporate monads whereby the apertures form in pairs at six points in the tetrad. The exine sculpture pattern is rugulate, scabrate or verrucate on mesocolpium but psilate, rugulate or microscabrate around the aperture on apocolpium. The exine of Korean Rhododendron pollen consists of tectum, columella, foot layer and endexine. The surface of viscin threads is more or less smooth. The threads are sometimes tangled together and occasionally divided into strands. Six types are recognized based on the pollen morphology. The types are: (1) Micranthum-type (rugulate mesocolpium and psilate apcolpium), (2) Tomentosum-type (rugulate mesocolpium and apocolpium), (3) Aureum-type (scabrate mesocolpium and rugulate apocolpium), (4) Brachycarpum-type (scabrate mesocolpium and rod shaped-microscabrate apocolpium), (5) Schlippenbachiitype (scabrate mesocolpium and round-microscabrate apocolpium) and (6) Weyrichii-type (verrucate mesocolpium).

• Journal of the East Asian Society of Dietary Life
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• v.10 no.4
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• pp.305-310
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• 2000

This study was attempted to investigate the effect of pine pollen on the chloroform toxicity in rat serum and liver. The subjects were administrated with the graded concentraton of tow different levels of chloroform(1%, 5%) and an additional amount of pollen (1%, 5%) to some groups. the results were as follows: The activity of aspartate aminotrasferase(AST), alanine aminotrasferase(ALT) and lactate dehydrogenase(LDH) in serum, liver, and kidney increased in proportion to the chloroform concentration, but decreased in the pine pollen-treated groups. The amount of total cholesterol in serum of he chloroform administration groups was higher than that of the control group, and it decreased gradually with pine pollen administration.