• Korean Journal of Weed Science
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• v.17 no.1
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• pp.44-51
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• 1997

Glyphosate had no effect on 5-enolpyruvylshikimate-3-phosphate synthase(EPSP-synthase) biosynthesis per se. But it inhibited clealy the activity of EPSP-synthase. EPSP-synthase seemed to be synthesized as a higher molecular weight(54 kDa) presusor protein and to be transported into plastid. The apparent molecular weight of mature EPSP-synthase in plastid is 45 kDa. Thus, the molecular size of transit peptide appeared to be about 9 kDa. The etiolation for 48 h after glyphosate application did not exhibit the inhibition of translocating level of EPSP-synthase across chloroplast envelope in actively growing meristematic leaves. But even when the plants were etiolated 2 hr after glyphosate treatment, a complete inhibition did not occur at least within 12 hr, i.e. 2 hr after beginning light period, suggesting that EPSP-synthase biosynthesis appeared to be not completely light dependent and the level of EPSP-synthase translocation to chloroplast could be controlled by an unknown regulatory mechanism of light dependent herbicidal effect of glyphosate.

• Journal of Korean Society of Forest Science
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• v.86 no.4
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• pp.430-434
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• 1997

Axillary bud explants from 3-year-old seedlings of Forsythia saxatilis N., rare and endangered species in Korea, were cultured on Murashige and Skoog's medium. The effect of various cytokinins(BAP, kinetin, and zeatin) at the different concentration(0.2, 0.5 and 1.0mg/L) was tested. Although an apparent shoot proliferation was not observed, zeatin showed slight promotional effect on normal shoot and leaf development. Both shoots and adventive roots could be induced simultaneously when the explants were cultured on the medium with kinetin, but adventive rooting was gradually reduced according as BAP and zeatin concentrations increased. Axillary shoot growth was promoted by the etiolation treatment. Shoot proliferation has been maintained more than three years with consecutive subculture. Rooted plantlets were successfully acclimatized in the artificial soil mixture and showed normal growth after transplantation into field.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.3
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• pp.400-406
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• 2010

Etiolation of plant leaves evoke to be photosynthetically inactive because plant leaves are unable to convert photochlorophyllide to chlorophyllide in the absence of light. In addition, UV-B radiation plays an important role in photomorphogenesis and excessive UV-B radiation decreases photosynthesis and causes to damage to cellular DNA. In the present study, two electrical lights obtained with the ultraviolet lamp and moderate lamp were employed to young plants soybean (Glycine max Merr. var Seoritae). After treatment of different lights, young plants were harvested for the determination of pigment contents and chlorophyll fluorescence. The contents of carotenoids and anthocyanins were significantly enhanced with the excessive UV-B radiation. Excessive UV-B light reduced dramatically photosynthetic efficiency causing an irreversible damage on PSII in comparison to the controls treated under normal illumination. As the treatment of normal illumination after dark treatment, the contents of carotenoids and anthocyanains were not changed in the leaves and photosynthetic ability were retained. Therefore, Seoritae soybean leaves might protect themselves from excessive UV-B radiation with up-regulation of antioxidants.

• Journal of Bio-Environment Control
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• v.16 no.2
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• pp.151-156
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• 2007

This work was conducted to investigate the important rooting factors through comparative analysis of a physiological differentiation after layering treatment using four apple rootstocks of different rooting abilities; M.26, M.9, O.3, and Mo.84. Mo.84 showed the highest rooting rate in from rootstocks, while O.3 was the lowest. Mo.84 also found to have the highest indole-3-acetic acid (IAA) content, although the fluctuation of IAA contents was not consistent with layering treatment. In contrast, abscisic acid (ABA) content of Mo.84 which showed highest rooting was lowest among rootstocks regardless of layering treatment. And ABA contents of all rootstocks were decreased after layering treatment than before layering treatment. O.3 which showed poor rooting rate revealed lowest in boron content. Carbohydrate/nitrogen (C/N) ratio of Mo.84 was the highest in all rootstocks. Therefor, we assumed that he IAA contents in layering treated rootstocks were not seemed to be a major rooting factor, but the changes in ABA contents and boron levels limit rooting in dwarf apple rootstocks.

• Korean Journal of Weed Science
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• v.6 no.1
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• pp.59-66
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• 1986

This experiment was conducted with pot trial to evaluate effects of pretilachlor [2-chloro-2', 6'-diethyl-N(n-propoxythyl) acetanilide], pyrazoxyfen [ 1,3-dimethyl-4-(2,4-dichloro benzoyl)-5-phenacyloxy-pyrazole], pyrazolate (4-(2,4-dichloro benzoyl)-1,3-dimethyl-pyrazol-5-yl-p-toluenesulphonate] and their combinations on Echinochloa crew-galli. Herbicides were treated with different dosages under 3 cm water depth at 1st and 2nd leaf stages of E. crus-galli. E. crus-galli showed stunted symptom by treatment of pretilachlor and etiolation by treatment of pyrazoxyfen or pyrazolate after 4 days from treatment. Stunting and chlorosis degrees of E. crusgalli increased with high dosage of all herbicides at lst and 2nd leaf stage. Combination of pyrazoxyfen+pretilachlor (6+1.5)G or pyrazolate+pretilachlor (6+1.5)G showed positive synergistic effect of herbicidal action on E. crus-galli, therefore these combinations can control E. crux galli in paddy field with lower dosage than each single treatment of herbicides. Herbicidal effect of pyrazoxyfen on E. crus-galli was similar to pyrazolate in single treatment and combination with pretilachlor.

• Journal of Life Science
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• v.19 no.6
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• pp.832-835
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• 2009

The main objective of this research was to improve rooting of M.9 apple rootstock through layering time, shading, layering material and water content of the layering part. Among the treatments, rooting was improved by mother plant shading or an earlier covering (layering in shoot length 2 cm) of shoots. Rooting and root growth of sawdust, chaff or vermiculite treatments were significantly higher than those of the control (soil). In the study of layering material water content, -40 kPa treatment increased rooting ratio, number of roots and root growth compared to -60 kPa treatment and control. These results suggest that early-covering, layering with sawdust, chaff, or vermiculite, and keeping the water content in the layering part at -40 kPa could improve rooting and root growth in M.9 rootstock propagation.

• Journal of Korean Society of Forest Science
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• v.102 no.1
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• pp.66-73
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• 2013

This study was conducted to determine the effects of rice hull cover on seed germination and tray types, soil types, shading conditions for seedling growth of Codonopsis pilosuala. We also examined the feasibility of cultivation of small seedlings transplanted in the Gyeonggi-do area for a month. Under control condition, the seed germination was 8% whereas it dramatically increased to 78% under rice hull cover treatment. Under the different conditions (tray types, soil types, and shading conditions), young seedlings showed the best quality without shading in TKS soil of 50 plug cell tray, with the growth characteristics of plant height (11.9 cm), number of leaves (71), leaf width (3.1 cm), leaf length (2.6 cm), and root length (14.3 cm). Seedling quality was the best without any shading in TKS+perlite, with the physiological characteristics of evaporation (3.9 $mmol{\cdot}m^{-2}s^{-1}$), carbon assimilation (9.1 ${\mu}mol{\cdot}m^{-2}s^{-1}$), and water use efficiency (2.2 ${\mu}mol{\cdot}m^{-2}s^{-1}$). Considering the economical, morphological, physiological and survival rate of the seedlings, it was an ideal method for transplanting seedlings in the field after they have been grown for 30-45 days in TKS and TKS+perlite of 200 plug cell tray in 0% or 30% shaded conditions. As the results of 5 months examination on the possibility to cultivate Codonopsis pilosuala in the Gyeonggi-do area, 88% to 96% of survival rate was observed with normal induced flowers. Therefore, cultivation of Codonopsis pilosuala was possible in the Gyeonggi-do area. While there were symptoms of etiolation and wilting under no shading condition, they did not appear in 30% and 70% shading conditions. Therefore, cultivation of Codonopsis pilosuala is considered to be necessary 30% or 70% shading.