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Kim, Young-Guk;Son, Seok-Yong;Park, Chung-Heon;Seong, Nak-Sul;Lee, Bong-Ho
- KOREAN JOURNAL OF CROP SCIENCE
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- v.45 no.4
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- pp.251-256
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- 2000
Astragalus membranaceus has flowers that are similar to that of the legume family, but shows poor bearing when self-pollination is induced. Thus, this study was carried out observing the ripening procedure of pistils and stamens and development stages of pollen in the context of the birth and growth of the flower. As to the bearing of the flower of A. membranaceus, few pod setting and 13% pod setting were observed when self-pollination is induced by paper-bag covering or artificial pollination treated respectively. The result indicates that A. membranaceus is a cross-pollination plant. A pistil grew faster than a stamen until just before blooming. The flower size was about 17.0mm$\times$4.0mm. Pistils and stamens had the same length after flowering. Pollen mother cells passed through meiosis and mitosis when its length reached around 3.5mm, thus creating the tetrade when 4 mm long. Pollen attained full growth when the bud was about 10mm long. An anther was found to tend to dehisce when the length of a bud reached around 12.0mm. As to the shape of pollen, about 70 % were normal. 1% and 30 % were small or empty pollen respectively. The result indicates that pollen of A. membranaceus attains full growth just before anther dehiscence which occurs before blooming while pistils grow faster than stamens until before flowering.
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J. K. Ahn;J. H. Lee;Y. S. Ham;B. S. Vergara;K. H. Kim
- KOREAN JOURNAL OF CROP SCIENCE
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- v.27 no.2
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- pp.99-106
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- 1982
Highly positive correlations were obtained between the growth duration of the 1978 IReTN entries in Chuncheon, Korea and all the experimental sites in 7 other countries. Among the entries the photoperiod responsive varieties had very long growth duration in Chuncheon although relatively early in flowering in the other low latitude sites. Selection under Korean conditions would eliminate the short growth duration varieties caused by photoperiod sensitivity in tropics or sub tropics. Except for photoperiod sensitive rices, selection of varieties or lines for optimum growth duration before further evaluation in other low temperature areas would be most effective in Chuncheon, Korea.
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Kim, Wook-Han;Hong, Byung-Hee
- KOREAN JOURNAL OF CROP SCIENCE
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- v.45 no.1
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- pp.1-5
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- 2000
Leaf area is critical for crop light interception, and thereby has a substantial influence on crop yield. This experiment was conducted to characterize the development of soybean [Glycine max (L.) Merr.] leaf area. Plastochron index and leaf relative growth rate of Jackson was contrasted with the PI416937, which also has demonstrated tolerance to drought. First, plastochron ratio (PR) and plastochron index (PI) were evaluated in greenhouse to compare the leaf growth rate between two genotypes under well-watered condition. There was reasonable constancy of PR between two genotypes. The PR means of Jackson and PI416937 were 0.41 and 0.44, respectively. A fairly smooth increase of PI during vegetative stage was observed. Second, the relative growth rates were graphed against leaf area, normalized with respect to final leaf area, under well-watered and water-deficit conditions. Leaf growth was sustained longer in well-watered condition than water-deficit condition and there was a sizable proportion of leaves which was ceased earlier their growth in water-deficit condition compared to well-watered condition. The leaf relative growth rate of Jackson until leaves had completed at 45% of their growth during water deficit period was higher than that of PI416937.
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Kim, Young-Guk;Kim, Kwan-Su;Bang, Jin-Ki;Yu, Hong-Seob;Lee, Seung-Tack
- Korean Journal of Medicinal Crop Science
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- v.6 no.2
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- pp.108-113
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- 1998
This study was investigated to elucidate the growth characteristics and the contents of glycyrrhizin and free sugars of Glycyrrhiza plants, i. e. G. glabra var. glandulifera, G. uralensis, and G. pallidiflora. The growth of G. glabra var. glandulifera and G. pallidiflora was better in plots planted with stolon and stem over 2cm in diameter compared to that of below 1cm and $1{\sim}2cm$. G. glabra var. glandulifera didn't bloom in Suwon but produced stolon, while G. pallidiflora bloomed but did not produce stolon. Total root weight of six-year-old G. glabra var. glandulifera consisted of stolon (73.2%) and primary root (26. 8 %). The contents of glycyrrhizin and free sugars were highest in stolon, followed by tap root and leaf. The glycyrrhizin contents in Glycyrrhiza plants were 7.38% in G. glabra var. glandulifera, 5.29% in G. uralensis and 0. 15% in G. pallidiflora.
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