• Korean Journal of Plant Resources
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• v.11 no.2
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• pp.168-172
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• 1998

The morphlogical characteristics and cytotoxic acitivity for14 local varieties fo Codonopsis lanceolata collected from Korea were examined to get basic data for breeding and selection of good cultivars. Plant height ranged from 197.2 cm to 253.2 com, that from Beakunsan(No.11) was the highest and and that form Samcheok(No.5) was the lowest. Generally, plant height of those form northern area of Korea tends to be shorter than those from Southern area. Leaf width and length of that form Husando (No. 12) was the largest While that form chejudo(No.4) was the smallest and those from other areas showed no significant difference. As to the number of branches, that form Yanggu(No.1) was theleast and those from other areas did not show Chejudo(No.14) were the heaviest. Among 14 varieties tested, Heongseong(No.3) and Huksando(No.6) exhibited strong cytotoxicity , which showed 45.0 an d62.0$\mu\textrm{g}$. $m\ell$ respectively.

• Korean Journal of Plant Resources
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• v.28 no.3
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• pp.357-362
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• 2015

Carbohydrate sources are one of important factors associated with macro- and micro nutrients and phytohormones in vitro culture medium for shoot growth. The optimal carbohydrates for eight species of the genus Prunus which are economically important fruit crop was evaluated at the initiation and elongation stages. All carbohydrate seemed utilized for the bud break and leaf growth at the early stage of culture. However, shoot elongation and fresh weight of species tested were superior in the medium containing 90 mM of fructose or glucose rather than sucrose. There was no difference between glucose and fructose. Adventitious shoots from the axillary buds were induced in most species but no significant differences were observed except for two species (P. salicina ‘Shiro’ and P. tomentosa). These result demonstrated that glucose and fructose were suitable carbohydrate sources for diverse Prunus species than sucrose, although the response to the carbohydrates in the medium were slightly different in the species.

• Journal of the Korean Institute of Landscape Architecture
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• v.31 no.6
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• pp.73-76
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• 2004

This study was conducted to investigate the growth responses of Polystichum lepidocaulon as influenced by 4 different shadings(Control, 50%, 70%, 90%). Under 50 or 70% shading, plant height, stipe length, blade length, blade width, and number of spores increased compared with the other shadings, except the number of frond and shoots. The plants grown under control was shown as smaller with more yellowish green leaf color, and under 90% shading the growth was slightly inferior to those under the 50 or 70% shading. Fresh weight and segment area of frond was better in increased shade levels, but they decreased in under 90% shading. Dry weight and segment thickness decreased as shading increased. Chlorophyll contents increased in proportion to lowered light intensity. Thus, 50 or 70% shading of Polystichum lepidocaulon seemed to maintain the highest growth.

• The Plant Pathology Journal
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• v.31 no.4
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• pp.421-427
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• 2015

Citrus scab disease is one of the destructive diseases that reduce the value of fruit for the fresh market. We analyzed the process of symptom development after infection with scab pathogen $Elsino{\ddot{e}}$ fawcettii in the susceptible satsuma mandarin leaves to observe the structural modification against pathogen. The cuticle and epidermal cells along with 3-5 layers of mesophyll tissue were degraded 1-2 days post inoculation. Surrounding peripheral cells of degraded tissues grew rapidly and then enveloped the necrotic area along with the growing conidia. Cross sections through the lesion revealed hyphal colonization in epidermis and mesophyll tissues. In response to the pathogen colonization, host cell walls were lignified, inner cells were rapidly compartmentalized and a semi-circular boundary was formed that separated the infected region from the non-infected region, and finally prevented the intercellular pathogen spread.

• Korean Journal of Plant Taxonomy
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• v.49 no.2
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• pp.107-117
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• 2019

Viburnum in Korea includes ten species. The phylogenetic relationships and morphology of the genus Viburnum in general have been studied substantially for the past three decades. A clear understanding of the systematic relationships and an assessment of the level of morphological variation of these plants distributed in Korea are lacking. This study investigated the morphology of these species using herbarium specimens and fresh materials obtained during fieldwork to examine the morphological variation level for a better understanding of each species in the genus. A comparative analysis showed that the species of Viburnum in Korea are easily distinguishable based on various characters of the bud, leaf, extrafloral nectary, inflorescence, corolla, fruit, and stone.

• Journal of Bio-Environment Control
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• v.26 no.2
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• pp.56-63
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• 2017

This study was carried out to establish qualities of watermelon seedling (Citrullus lanatus) according to raising seedling period (RSP; 40, 45, 50, 55, 60, and 65 days) and was carried out to investigate growth characteristics after planting of the seedlings. In seedling qualities according to RSP, Plant height, stem diameter, leaf area of seedling with RSP 65 treatment were significantly increased. Fresh and dry weight in the above of corp showed a significant difference among the seedlings with RSP 40-45, RSP 50-60 and RSP 65 treatment, and that in of root were significantly higher in the seedlings with RSP 40, 45, 65 treatments than with other RSP treatments. S/R ratio was lower in the seedlings with RSP 40 and 45 treatments than with other RSP treatments. RSP affected to the leaf area and S/R ratio of seedling. After 11 weeks after planting of a various seedlings, except that height and node number of plant with 45 RSP treatment was lower than other RSP treatments, other growth characteristics were not significantly different amon RSP treatments. Leaf area, fresh weight, dry weight and S/R ratio were lowest in plant with RSP 65 treatment. Relative growth rate and net assimilation rate of planted watermelon tended to decrease and leaf area ratio was continuously increased until 9th week in the all treatments. The lighter and heavier fruit were produced in plants with RSP 40 and RSP 65 treatments (9.7 kg and 9.9 kg) and in RSP 50 and RSP 55 treatments (both 11.0kg), respectively. Fruit sugar contents was highest in fruit with RSP 45 treatment, and was lowest in RSP 50 and RSP 60 treatments. RSP showed a polynomial regression relation with the increment of fruit weight and the weight of harvested fruit. Considering the increment and weight of fruit, the most for RSP of watermelon seedling for planting were 50-55 days.

• Korean Journal of Weed Science
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• v.8 no.3
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• pp.273-282
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• 1988

The seventeen barnyardgrass [Echinochloa crus-galli (L.) Beauv.] accessions, which were collected national-widely in 1986 and selected two times through 1987, were experimented at 1988. To study the degree of ecological variations of the collected accessions of native barngardgrass species as a weed, the experiment was conducted with Wagner pots in size of 1/5000a and under P.E. film house. Among 57 characters, 100 grains weight, rate of tiller increase from transplanting to 30 days, the number of the maximum tillers and rate of dry weight increase from 15 DAS to 22 DAS were become intra-specific variarions as higher coefficient of varation than 30%, the size of the first leaf, fresh weight and dry 22 seedlings, rate of productive tiller, panicle number and tillering divergence made intra-specific variations as more and less C. V. than 25%, while the required days upto heading since seeding at June 6. rate of fresh/dry weight and plant height of 22 days old seedling made intra-specific variations as the coefficient of variation of about 50%. Among the attributes the color in leaf, leaf sheath, mid-ribs, node, spike, grain, and plant type, length of leaf marginal tooth, grain shape, purple bend on leaf were seemed useful to indentify the accessible specific.

• Journal of Korean Society of Forest Science
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• v.100 no.4
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• pp.609-615
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• 2011

Forsythia saxatilis is a Korean endemic plant designated as rare and endangered by the Korea Forest Service (KFS). Growth and physiological characteristics of F. saxatilis were investigated under two different light intensities in order to figure out an appropriate growth environment for conservation and restoration of the species in its natural habitat. Shoot length, leaf size and weight, photosynthetic pigment content and photosynthetic parameters were measured for F. saxatilis grown at two experimental plots under relative light intensities (RLI) of 20% and 60% of the full sun, respectively. Fresh leaf weight of plants grown under high relative light intensities (RLI-60) exceeded that of plants grown at 20% RLI. The ratio of fresh leaf weight to leaf size at RLI-60 was 1.47 times superior comparing to that recorded at RLI-20. The content of photosynthetic pigments such as chlorophyll a, b and carotenoid were higher in plants grown at RLI-60, whereas the ratio of total chlorophyll to carotenoid content was higher in the leaves at RLI-20. Photosynthetic rate, stomatal conductance and transpiration rate at RLI-60 were, respectively, 2.5, 2.65 and 1.79 times higher comparing to those recorded at RLI-20. Water use efficiency, however, was higher at RLI-20. The chlorophyll/nitrogen ratio was 1.83 times higher at RLI-20 than at RLI-60. In contrast, the ratio of net photosynthesis to chlorophyll content at RLI-60 was 2.58 times higher than that of RLI-20. In conclusion, light intensity might be the major factor affecting growth and physiological characteristics of F. saxatilis grown under canopy of tall tree species.

• Korean Journal of Agricultural Science
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• v.2 no.2
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• pp.341-356
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• 1975

This study was carried out to evaluate three winter active synthetic varieties in a succeeding generations of improvement and polycross progenies of seven genotypes selected at the cool and wet climate of the Western Oregon, in their performance of the polycross progeny test comparing with a control variety, high yielding 'Fawn', at Daejon, Korea. Various plant and leaf characteristics, especially related to photosynthesis, and forage production during the first summer after the establishment were examined. The important conclusions of this study are summarized as follows: 1. The differences of leaf fresh weight among groups and control exhibit genetic differences. The a verage of leaf fresh weight of polycross progeny group was the heaviest and those of winter active synthetic varieties in the succeeding generations of improvement was heavier than variety 'fawn'. Within polycross progeny group the genotypes exhibit genetic differences for leaf dry weight. 2. The leaf area exhibited genetic differences among groups and control. The average of winter active synthetic varieties in a succeeding generation was larger than variety 'Fawn'. Those oi the polycross progeny group was the largest among groups and control. 3. Differences of specific leaf weight(S. L. W.) among and within varieties, genotypes and control were not significant. Further investigation in this respect is necessary through the study of the diurnal change in S. L. W. 4. Differences of leaf width among groups and control exhibited genetic differences. The average leaf width of winter active varieties was larger than those of 'Fawn' variety. And those of polycross progenies of genotypes was the largest. 5. Plant height of 'fawn' variety in the first measurement was higher than those of winter active tall fescue varieties and genotypes. The deviation in plant height among polyeross progenies of seven genotypes gave a great deviation. The regrowth ability of plant height was not different suggesting that this characteristics was about the same among and within groups and control. 6. Plant width, spreading ability, improved through the succeeding generations of the improvement of the winter active synthetic varieties for the first measurement. Differences of plant width at the second measurement among genotypes within polycross progeny group were big enough to show the genetic difference. 7. Tiller number of the winter active synthetic varieties and the average of genotypes in polycross progeny was more than those of the control 'Fawn' in the first measurement. On the second measurement, the differences of tiller number appeared among three synthetic varieties indicating improvement, and there were genetic differences among seven genotypes in polycross progeny test. 8. Forage yield on the first cutting showed a considerble improvement of forage yield in the more advanced generation of synthetic varieties and genetic differences among seven genotypes in the polycross progeny test. The average of polycross progeny group was higher than those of the control or three winter active varieties. It was suggested that we could make a further improvement for the forage yield. 9. The regrowth ability of these winter active varieties and genotypes was about the same capacity at least on the measurement of the regrowth in forage yield and plant height during summer. 10. On the whole, the averages of the polycross progeny group was in the highest value and those of synthetic varieties were higher than the control variety, 'Fawn', for the most characteristics except S. L. W. and the plant height on the first measurement even though the differences were not always significant. And there were genetic differences among seven gentypes in their performance of the polycross progeny. 11. Although it was not always sgnificant, the most advanced winter active variety, '1002', had in the highest value for all plant characteristics and forage yield measurements than the other two varieties, '1001'. 12. The results of the association study among various characteristics were quite agreeable and would be useful in the selection of desirable genotypes for the development of a better variety.

• Korean Journal of Soil Science and Fertilizer
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• v.25 no.2
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• pp.160-167
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• 1992

The growth of weeds and some other plants has been considered to be inhibited by sicklepod(Cassia tora L.) sharing the habitat. The study was conducted, for the first time, to propose that this phenomenon is not only due to competition for physical and nutritional conditions but also due to allelopathy. In addition, autotoxicity of sicklepod was examined. The results are summarized as follows. 1. Rice sheath length reduced progressively from 18 % to 36 % with increasing the concentration of treating aqueous extracts of sickle pod seeds, but rice germination was not affected. In contrast, radish hypocotyl length was not reduced by the aqueous extract treatment but radish germination was significantly reduced by 66 % at 1 : 10 and 1 : 5 treatment. 2. Total chlorophyll contents in rice seedling decreased from 50 % to 65 % by treatment of seed aqueous extracts diluted from 1 : 50 to 1 : 5 ratio. 3. Aqueous extracts of sicklepod leaves significantly reduced hypocotyl length and fresh weight in radish and germination in rice, but mung bean was slightly affected by aqueous extracts only in fresh weight. 4. Volatiles from fresh, immature seeds with husk reduced the radish germination and seedling growth and radish root growth appeared to be more sensitive to the exposure to volatiles from fresh immature seeds than both germination and hypocotyl growth. 5. Volatiles from sickepod leaves inhibited germination and growth of radish, rice and mung bean, and seedling growth was more sensitive to volatiles from leaves than germination. 6. Volatiles from sicklepod leaves reduced germination and radicle length of sicklepod itself. 7. Collectively, it is concluded that there are water-soluble and volatile substances responsible for allelopathy in sicklepod.