• KOREAN JOURNAL OF CROP SCIENCE
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• v.34 no.1
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• pp.106-112
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• 1989

To investigate varietal differences of anther size, pollen shape, pollen fertility and other agronomic characters under low temperature condition. twenty rice varieties (5 Tongil and 15 Japonica type) were treated at 19$^{\circ}C$ water temperature from booting to heading stage. There was varietal difference of low temperature response which was indicated by the delayed heading, the shortening of culm and panicle length. and the decrease of grain fertility and yield potential resulted from cooling treatment at booting stage. The varieties with low fertility damaged by the low temperature treatment at booting stage showed low pollen density per anther. small or abnormal anthers and pollen, and many sterile pollens. Anther length was correlated significantly with the number of pollens per anther and pollen fertility.

• Applied Microscopy
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• v.35 no.4
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• pp.74-83
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• 2005

The ontogeny of pollen wall in Panax ginseng was studied with transmission and scanning electron microscopy from early tetrad stage until pollen maturity. Initial indication of exine development is undulation of plasma membrane for the preparation of bacular mound. The first recognizable structure of the pollen wall is the cellulosic primexine which is formed outside of the plasma membrane while microspore tetrads are still surrounded by callose wall. As development proceeds, foot-layer and baculum differentiation, callose dissolution and exine formation were progressed. During this process, sporopollenin is deposited into the exine, and then endexine development was followed. The intine, innermost pollen wall layer, is developing form hypertrophic Golgi vesicles. The thickness of exine is very even on all along the pollen wall, but intine thickness of apertural region is thicker than that of nonapertural region. Mature pollen of ginseng is $20{\mu}m$ in size, tricolpate and shows fine reticulate sculpturing.

• Journal of the Korean Geographical Society
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• v.47 no.2
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• pp.179-192
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• 2012

Paleo-environments such as vegetation and climate changes from the Last Glacial Maximum to the Holocene are reconstructed by the results of pollen analysis in the floodplain of Cheonan River, Seongjeong-dong, Cheonan-si, Chungnam Province. In the pollen zone I (approximately 23,000-15,000 yr BP), the area studied was covered by the extensive grassland with sparse wood. The climatic conditions were very cold, but it might not be so severe compared to the intermontane area in the Yeongnam area. This zone corresponds to the 'very cold' stage of Woldstedt(1962) and Yoon and Jo(1996). No pollen horizon(pollen zone II) deposited between approximately 15,000 and 10,000 yr BP corresponds to the transitional stage from the Last Glacial Maximum to the Holocene. The horizon consists of the dark gray brown sand deposits different from the other horizons dominated by the silty deposits and these sedimentary properties may be attributed to the dramatic climate changes between the very cold stage and warm stage. The pollen zone III formed between approximately 10,000 and 6,000 yr BP shows clearly different pollen compositions indicative of temperate climate conditions.

• Journal of Plant Biotechnology
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• v.30 no.1
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• pp.35-40
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• 2003

In this study we investigated the effect of gametocides on the number of larger-sized pollen in anther, and also induced callus from the anther culture of Zoysia japonica Steud. Before culturing, we have observed pollens in anther through fluorescence and electron microscopes to know pollen dimorphism. There were two types of pollens observed. One type (30-36 ${\mu}{\textrm}{m}$ in diameter) consisted of vacuolated, larger-sized pollens and the other (15-20 ${\mu}{\textrm}{m}$ in diameter) smaller-sized ones with dense cytoplasm and plenty of amyloplasts. Within few hours, all the smaller-sized pollens were dead, while larger-sized ones were viable for one or two days. To induct larger-sized pollens, various gametocides were leaf-sprayed on three booting stages cultured under 4$0^{\circ}C$ /15$^{\circ}C$ (day/night) before anther culturing. Number of these larger pollens were few (less than 1%) in anther without spraying gametocides. GA$_3$increased the number of larger-sized pollens when applied at mid-booting stage. GA$_3$ with 50 mg/L treatment caused the highest percentage (25.4%) of the larger-sized pollen. Anthers with GA$_3$ treatment were only produced calli on AA medium (modified B$_{5}$+8.0 mg/L 2,4-D ＋0.2 mg/L kinetin), but callus formation was quite low (less than 1%).).

• Culinary science and hospitality research
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• v.10 no.4
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• pp.178-189
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• 2004

This study was performed to investigate the effects of pine pollen and horseradish, which were known as antimicrobial materials, on the fermentation of Kimchi. The physicochemical and microbial changes of Kimchi were investigated during period 30-days at $10^{\circ}C$. Even though Kimchi added pine pollen or horseradish powder were sustained the higher pH and lower acidity after 10 days, it delayed only 1∼2 more days to reach optimal value of Kimchi fermentation in experimental groups than control. The horseradish powder showed the antimicrobial effect of Kimchi at initial stage, but thereafter that effect of pine pollen or horseradish were not significant. Therefore the addition of pine pollen or horseradish powder to Kimchi is not sufficiently effective for extension of shelf-life of Kimchi.

• The Korean Journal of Ecology
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• v.21 no.2
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• pp.169-174
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• 1998

This is the review of vegetational history of the post-glacial period in Korea. most of studies for vegetational changes are located in the lowland alluvial plain, especially below the hilly zone of western and eastern coastal regions of Korea. A couple of methods, pollen analysis and radiocarbon dating, have been employed in these studies. These results lead us to establish the pollen zonation in Korea as the followings. Yasuda et al.(1980) classified six period in Yongrang lake of sokcho. These are as follow I. 17,000-15,000yr B.P.: Picea, Abies, Pinus(Haploxylon), Larix stage, II.15,000-10,000yr B.P:Herb, Pteridophyta stage, III.10.000-6,700yr BP.:Quercus stage, IV.6,700-4,500yr B.P.:Pinus, Quercus, Carpinus stage, V.4,500-1,400yr B.P.:Quercus. Pinus stage, VI.1,400yr B.P.-present: Pinus, Herbs stage. Jo(1979) also divided the period into two stages from the outcomes of analysis done in Jumoonjin and other sites I.10,000-6,000yr B.P.:Quercus stage, II.6,000-present: Pinus-Quercus stage, and three substages: IIa.6,000-3,400 yr B.P.:lower Pinus stage, IIb.3,400-2,000yr B.P.:Pinus-Quercus stage, IIc.2,000-present: Pinus stage. Choi(1993, 1996) divided the period into three stages: I.6,000-5,000yr B.P.:Alnus, Quercus stage, II.5,000-4,000yr B.P.: Alnus, Quercus, Pinus stage, III.4,500-2,600yr B.P.: Alnus, Pinus stage. In the period around 6,000yr B.P. distinct dominant species clearly occupied the lowland of the eastern and western coasts. Thus, this strongly supports the fact that even if Korea experienced its warm and wet climate after the lateglacial, it underwent a different environmental change, dry climate, compared to the regions of Japan.

• KSBB Journal
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• v.17 no.6
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• pp.577-581
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• 2002

In an attempt to produce recombinant proteins using the pollen enriched in some plant species, a 1.7 kb DNA encoding urease subunit B (UreB) amplified by PCR from Helicobacter pylori urease gene cluster in pH808 plasmid was cloned to be expressed under CaMV35S promoter in lily (Lilium longiflorum) pollen tubes elongated in vitro. Lily pollen at early germinating stage was transformed with the ureB DNA using Agrobacterium via vacuum infiltration and, incubated for a full pollen tube growth 16 - 24 h in the dark in the presence of kanamycin. DNA integration and expression in the transgenic pollen were analyzed by the standard molecular techniques and the results suggest that the pollen in vitro may be employed as a protein factory in a disposable fashion.

• Korean Journal of Plant Tissue Culture
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• v.21 no.5
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• pp.293-297
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• 1994

In order to induce immature pollen derived plants, anthers of Ranunculus japonicus Thunb. were cultured on Murashige and Skoog's medium supplemented with various combinations of auxins and cytokinins. The combinations of NAA and BA were more effective than those of 2,4-D and kinetin in the formation of calli and embryos. Up to 5t5% of the anthers cultured on medium containing 0.5 mg/L NAA and 1.0 mg/L BA gave rise to plantlets. The most suitable stage for anther culture in the induction of calli and/or embryos from immature pollens was at the uninucleate and early binucleate stage (3 days before anthesis). Immature pollens developed into embryos by repeated division of the vegetative nucleate after 60days of culture.

• Korean Journal of Plant Tissue Culture
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• v.26 no.3
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• pp.149-156
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• 1999

In order to investigate the effect of low temperature pretreatment on pollen dimorphism and embryo formation in anther culture of Platycodon grandiflorum, the anthers with microspore at the uninucleate stage were cultured on Murashige and Skoog medium supplemented with 0.5mg/L NAA and 1.0 mg/L BA. The low temperature pretreatment have clear effect on the frequencies of S pollen grains, symmetrical binucleate microspores (B type of S pollen), multinucleate and multicelled pollen grains. Especially, after low temperature pretreatment at 8$^{\circ}C$ for 5 days increased the frequency of S pollen grain (20.6%) in vivo. In addition, the highest frequency of callus induction (54.9%) and embryo formation (9.9%) were obtained from the anther pretreatment at 8$^{\circ}C$ or 5 days. Three distinct pathways could be recognized in the androgenesis, one involving mainly the vegetative cell, the second starting with the vegetative and the generative cell, respectively, and the third accompaning with two equal vegetative type cells in the pollen grains.

• Proceedings of the Botanical Society of Korea Conference
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• 1996.07a
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• pp.48-60
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• 1996

We previously identified and characterized a predominantly pollen-expressed gene of Petunia inflata that encodes a receptor-like kinase named PRK1. The extracellular domain of PRK1 contains leucine-rich repeats which have been implicated in protein-protein interactions, and the cytoplasmic domain was found to autophosphorylate on serine and tyrosine. To investigate the function PRK1 in pollen development, we transformed P. inflata plants with a construct containing the promoter of a predominantly pollen-expressed gene of tomato, LAT52, fused to an antisense PRK1 cDNA corresponding to part of the extracellular domain of PRK1, There transgenic plants were found to each produce approximately equal amounts of normal and aborted pollen. Analysis of the inheritance of the transgene inserts in two of the transgenic plants, ASRK-13 and ASRK-20, to their progeny revealed that certain transgene inserts cosegregated with the pollen abortion phenotype. Microscopic examination of the aborted pollen grains showed that their outer wall, the exine, was essentially normal, but that their cytoplasm contained only starch-like granules. Staining of the nuclei of the microspores at different stages of uninucleate stage. However, at subsequent stages half of the microspores completed mitosis and developed into normal binucleate pollen, but the other half initially remained uninucleate, then lost their nucleio. Analysis of the amounts of PRK1 mRNA and the antisense PRK1 transcript suggested that the pollen abortion phenotype most likely resulted from down-regulation of the PRK1 gene by the antisense PRK1 transgene. These results suggest that PRK1 plays an essential role in a signal transduction pathway that mediates post-meiotic development of microspores.