• The Korean Journal of Ecology
• /
• v.24 no.3
• /
• pp.157-168
• /
• 2001

Herbicides have been used to control weeds for decades. If detoxification upon exposure to herbicides requires considerable amounts of energy, it could affect the pattern of resource allocation to growth and reproduction of crops. We examined the effects of three levels of a herbicide (Control, Low, and High) on germination, growth and reproductive characters of Glycine max treated twice, i.e., before and after seed germination. Since flowering time of G. max was separated into two groups, flowering time was also considered as a variable in this study. The rate of seed germination tended to be higher at the low level of herbicide compared to other levels. Chlorosis and shape variation of leaves were apparent after the second herbicide treatment, but completely disappeared after six weeks of treatment. The herbicide effects on growth characters were somewhat different between early and late flowering plants, but plants treated with both low and high levels of herbicide reduced their growth compared to those in the control group regardless of flowering time. Plants at the high level of herbicide exhibited the highest growth rate later in the season, suggesting that plants compensated to some extent for reduced growth. However, growth reduction among plants at the high level of herbicide was persistent until the end of growing season. Among plants flowered late in the season, plants in the control level bore a higher number of nodules per plant than those in other levels; such a pattern did not exist among plants flowered early in the season. Plants treated with low and high levels of herbicide produced a lower number of flowers than those in the control. Thus, the herbicide examined affected not only the growth and reproductive characters of non-target crops but also the development and growth of root nodules.

• Journal of Nutrition and Health
• /
• v.41 no.1
• /
• pp.77-88
• /
• 2008

This research was carried out a to investigate the food habit and preference of parents' social and economic level with 681 children (145 of Kindergarten, 300 of Children, 236 of Adolescences) in Seoul and Gyeonggi area using question naires. The parents' income level divided into 2 groups, less than 4 million won and equal or greater than 4 million won. Most of the middle years were over-weighing but kindergarten and adolescences had standard weights. The majority of parents had Bachelor degrees, most of father were office workers, majority of mothers of kindergarten with parents' income level less than 4 million won were professional women and mothers of the rest of the groups were mostly house wives. The middle years with parents income level less than 4 million son were skipping meals most frequently, but other groups didn't show much differences in their eating habits. All age groups showed that they like meats the most and dislike vegetables the worst. All age groups also showed that they mostly eat out 1-2 times a week and the next was 3-4 times a week. All age groups preferred ice creams, fruits, juices and snacks for their desserts. The middle years with parents' income equal or greater than 4 million won also showed high preference on strawberry and chocolate flavored milk, burgers and pizzas. The food s that preferred to eat when dining out were Chinese foods (Ja-jang-myeon and sweet and sour pork) for kindergarten group, Korean foods (kalbi and bulgogi) for the middle years with parents' income level less than 4 million won, family restaurant food (steak and rib) for the middle years with parents' income level equal or greater than 4 million won and Korean foods (kalbi and bulgogi) for the adolescences. The preferred cooking methods were roast (fish and sea weeds) for the kindergarten, roasted meat for the middle years, Kimchi and bean paste pot stew for the adolescences with parents' income level less than 4 million won and roasted meats for the adolescences with parents' income level equal or greater than 4 million won. The results showed that the adolescences with higher parental income lever preferred meats.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.34 no.9
• /
• pp.1464-1470
• /
• 2005

To assure the safety of the major edible seaweeds, we collected the 176 samples of seaweeds such as laver(Porphyra sp.), sea mustard (Undaria pinnatifida), sea tangle (Laminaria japonica) and sea lettuce (Enter-omorph sp.) from Korean coast. We investigated the contents of the trace metals in the edible seaweeds, and the values were expressed as the dry weight of sea weeds. The mean levels of the trace metals were high in the oder of Zn ($36.19{\pm}27.14 \;{\mu}g/g$), Mn ($28.75{\pm}28.03\;{\mu}g/g$), and Cu ($6.82{\pm}7.62\;{\mu}g/g$), which are necessary metals in the human body, and then followed by Cr ($1.54{\pm}2.07\;{\mu}g/g$), Ni ($1.29{\pm}2.57\;{\mu}g/g$), Pb ($0.89{\pm}1.11\;{\mu}g/g$), Cd ($0.72{\pm}0.80\;{\mu}g/g$) and Hg ($0.01{\pm}0.02\;{\mu}g/g$). The contents of Cd and Zn were high in the laver, Cr, Ni and Pb were detected highly in sea lettuce, and Hg was detected highly in sea tangle. Significant linear correlations were obtained among 28 different pairs of metals, some of them highly correlated (r>0.5, p<0.05),such as Ni-Mn, Zn-Ni, Cu-Pb and Cu-Zn in laver, Ni-Zn in sea mustard, Cu-Pb, Cu-Zn and Mn-Pb in sea tangle, and Ni-Cr in sea lettuce. And, the trace metal contents of seaweeds varied with parts and kinds of samples. The average weekly intakes of Hg, Cd and Pb from seaweeds were about $0.07{\~}3.57\%$ of PTWI (Provisional Tolerable Weekly Intakes) which has set by FAO/WHO to evaluate the safeties of trace metals in food. Therefore, it was found that they showed very safe levels in the edible seaweeds.

• Economic and Environmental Geology
• /
• v.37 no.5
• /
• pp.569-583
• /
• 2004

The rock properties of the West pagoda in the Gameunsaji temple site are composed mainly of dark grey porphyritic granodiorite with medium grained equigranular texture and developed with small numerous dioritic xenoliths. These xenoliths occurred with small holes due to different weathering processes. As a weathering results, the rock properties of this pagoda occur wholly softened to physical hardness because of a complex result of petrological, meteorological and biological causes. Southeastern part of the pagoda deteriorated seriously that the surface of rock blocks showed partially exfoliations, fractures, open cavities in course of granular decomposition of minerals, sea water spray and crystallization of salt from the eastern coast. The Joint between blocks has small or large fracture cross each other, contaminated and corrupted for inserting with concrete, cement mortar, rock fragments and iron plates, and partially accelerated coloration and fractures. There are serious contamination materials of algae, fungus, lichen and bryophytes on the margin and the surface on the roof stone of the pagoda, so it'll require conservation treatment biochemically for releasing vegetation inhabiting on the surface and the discontinuous plane of the blocks because of adding the weathering activity of stones and growing weeds naturally by soil processing on the fissure zone. Consisting rock for the conservation and restoration of the pagoda would be careful choice of new rock properties and epoxy to reinforce for the deterioration surfaces. For the attenuation of secondary contamination and surface humidity, the possible conservation treatments are needed.

• Korean Journal of Weed Science
• /
• v.10 no.4
• /
• pp.312-327
• /
• 1990

Weed species investigated on the roadways of Kyungnam and Kyungpook provinces in September, 1989 were 75 species in 31 families and 89 species in 31 families, respectively. Five weed community types were observed on the roadway of Kyungnam province, namely, Kummerowis striata, Humulus japonicum-Artermisia princeps, Digitaria sanguiralis-Eleusine indica, Artermisia princeps-Degitarin sanguinalis and Digilaria sanguinalis-Setaria viridis. In contrast, Kyungpook province had six community types which were Eleusine indica, Humulus japonicum-Commelina communis, Ihgitaria sanguinalis-Eeusine indica, Digitaria sanguinalis-Artermisia princeps, Dzgitaria sanguinalis-Setaria viridis and Setaria viridis community types. Ten major weed species on the roadway of Kyungnam province were Dtgitaria sanguinalis(23.3%). Setaria viradis(8.3%). Edeusine indica(7.3%). Kummerowis striata(6.0%). Humulus japonicum(5.2%), Phaseolus nipponensis(3.5%), Echinochloa crusgalli (2.9%) and Imperata cyliudrica(2.0%). On the roadway of Kyungpook province, ten major weeds were Digitaria sanguinalis (25.4%). Setaria viridis (10.5%). Eleusine indica(9.0%). Humulus japonicum(8.6%). Eragrostis fernsginea(6.5%), Artermisia princeps(3.8%), commelia communis(2.2%), Irexis dentata(1.8%), Equisetum arvense(1.8%) and Kummerowis striata (1.7%).

• Korean Journal of Weed Science
• /
• v.1 no.1
• /
• pp.30-43
• /
• 1981

On unwedded paddy fields, six cropping patterns of rice cultivation, namely direct broadcast seeding, direct row seeding, machine transplanting, early season hand transplanting, standard season hand transplanting, and late season hand transplanting, were detected with two representative rice cultivars (Milyang 23 and Sadominori) to estimate the comparative fluctuation patterns of weed flora. As a result, number of emerged weed species, most crowding stages, differences of weed growth among cropping patterns, possible tendencies of competition in plant heights among plant groups, variations in Importance Values, and Simpson's Index analysis were discussed, respectively.

• Korean Journal of Weed Science
• /
• v.31 no.3
• /
• pp.294-307
• /
• 2011

This experiment carried out to confirm characteristics of macrogranule (GG) for herbicidal efficacy by using remote-controlled aerial application (RCAA) to control annual and perennial weeds in rice paddy field, application methods, and application times of formulation types. Particle of 500 g GG having average diameter of 2.5~3 mm was over 85 percent, the bulk density of the particle was $0.2\sim0.4g\;mL^{-1}$ and the particle was water floating granule. Active ingredients and external form of halosulfuronmethyl+mefenacet GG remained stable under condition of storage stability test. The disintegration time of the GG was faster as the water temperature was increased. But disintegration time was not affected by pH on the water conditions. By using hand, spoon and power applicator, drift distances of GG were 4~5m, 7 m and 10~12 m, respectively. GG showed good herbicidal efficacy and plant safety in all of the application methods such as, using hand, spoon, power applicator and RCAA. Application times of GG, GR, SC and TB by hand in $4,000m^2$ were 38 min. 4 sec, 42 min. 20 sec, 38 min. 10 sec and 21 min. 4 sec, respectively, but application time of GG by using RCAA was 1 min 32 sec. According to appearance and characteristics of formulation types, suspension concentrate (SC) and GG were possible formulation types for RCAA.

• Korean Journal of Weed Science
• /
• v.31 no.3
• /
• pp.250-259
• /
• 2011

This study was conducted to assess the possibility of 5,8-dihydroxy-1,4-naphthoquinone (DHNQ) as a environmental friendly herbicide candidate. Foliar application of DHNQ showed excellent herbicidal effect to the 3 grasses and 5 broad-leaved weeds. Among them, Digitaria sanguinalis and Solanum nigrum were completely controlled by $250{\mu}g\;mL^{-1}$ of DHNQ with main symptoms of desiccation or burndown within 24 hours. Aeschynomene indica was also sensitive to DHNQ treatment. All of the eight weed species were controlled by 90~100% at a concentration of $1000{\mu}g\;mL^{-1}$. However, soil application of DHNQ to Digitaria sanguinalis did not show any herbicidal symptoms. DHNQ strongly inhibited KAPAS activities in vitro and the $IC_{50}$ was $4.4{\mu}M$. Cellular leakage from cucumber leaf squares treated with DHNQ increased depending on the concentrations increased from 6.25 to $100{\mu}M$ after 24 hours incubation with or without light. However, chlorophyll loss in cucumber leaf squares was negligible. Biotin supplements significantly rescued the inhibition of germination rate of Arabidopsis thaliana seeds previously inhibited by the DHNQ. According to above results, DHNQ is a good natural herbicide candidate having a new target KAPAS, which is involved in biotin biosynthesis pathway, with environmental friendly.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.7 no.1
• /
• pp.63-69
• /
• 1987

This field experiment was undertaken to assess the effectiveness of magnesium- and boronenriched complex fertilizer ($N-P_2O_5-K_2O-MgO-B_2O_3$ : 8-25-7-3-0.2) compared with some straight fertilizers on the hilly pasture establishment. This second part was concerned with the changes in the forage yields, yield components, botanical and chemical compositions in a mixed grassclover sward (orchardgrass, tall fescue, Kentucky bluegrass, and ladino clover). The results from a two-year experiment are summarized as follows: 1. Dry matter yields of whole mixed forages were significantly reduced in control by 54.5% and the NK-plot ($P_o$ by 35.0%, compared with the normal NPK-plots. 2. The yields of oversown grasses were significantly reduced in control by 79.7% and the NKplot ($P_o$) by 52.196, compared with the normal NPK applications. At the normal NPK applications, the oversown grasses were lowest in the yields when provided with double superphosphate with no significant differences. The yields of weeds were not significantly influenced by the treatments. 3. The significant differences in the legume yields (relative yield, %) were laid in the follow. ing increasing order; complex fertilizer (178.5%) > NPK-fused superphosphate (139.5%) > NPK-double superphosphate (100.0%) = control > NK (51.1%). The legume yield was much more depressed in the NK-plot ($P_o$) than in control ($N_oP_oK_o$). 4. The rate of oversown grasses and whole forages were increased by the normal NPK applications, showing little difference among the kinds of fertilizers. It was recognized that the application of complex fertilizer contributed to the increasing of legume rate in the mixed sward. This contribution turned out to be due to the rather enhanced performance and yield-increase of legume, compared with the straight fertilizers. 5. With the NK-treatment ($P_o$) the P concentration in mixed forages dropped below the critical level (0.2%). The Mg concentrations in mixed forages were lower in all the plots than the critical level (0.2%). Therefore, a sufficient amount of Mg was desirably to be applied It is recommended that, in relation to its effectiveness and simplification of fertilizer application, the application of this complex fertilizer for pasture establishment be carried out. The change of the constituent ratio of complex fertilizer to the standard of "8 - 15-20 - 7 - 5-10 - 0.2" considering the need of sufficient Mg supply and the continuous accumulation of P in the top-surface soil is possibly recommended.commended.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.6 no.1
• /
• pp.31-37
• /
• 1986

In order to study the possibility of grassland improvement by spring sowing in the forest, microenvironmental conditions, emergence, percentage of grasses and weeds, root weight and dry matter yield of grasses were investigated. Two field sites (forest grassland and full-sunlight grassland) and two sowing times (March 20 and April 10) were assigned. The condition of the forest grassland was area of pine trees with 50% shading, and the experiment was performed at the Livestock Experiment Station in Suweon, 1984. The results obtained are summarized as follows: 1. For germination and early growth of grasses, full-sunlight grassland was more advantageous than forest grassland. Growth after that stage, on the other hand, forest grassland was more suitable. Especially, during dry and high temperature season, temperature of soil surface and underground in the forest grassland were decreased by $6-7^{\circ}C$ and $3-4^{\circ}C$ each other, compared with those of the full-sunlight grassland. Also soil moisture content was continuously higher in the forest grassland. 2. At March 20 sowing the emergence time in the full-sunlight grassland was shortened by 8 days, compared with that of the forest grassland. In case of sowing on April 10, however, there was no difference between two grassland sites. 3. Grasses grown in the forest was more prostrate and leaves from them decayed more, compared with those of the full-sunlight grassland. 4. The percentage of grasses in the forest grassland was 80 to 85 %, on the other hand, that of the full-sunlight grassland was only 15 to 20 %. And the percentage of grasses tended to be high in the plot of early sowing time. 5. Dry root weight and root length of grasses grown in the forest were inferior to those of the full-sunlight grassland (P<0.05), but there was no significant difference between two sowing times. 6. Dry matter yield of grasses was significantly higher (P<0.05) in the forest grassland than in the full-sunlight grassland, and yield was influenced by sowing time. Higher yield (4,011 kg/ha) was produced in the plot of the forest grassland with early spring sowing. 7. From above results, it is suggested that grassland improvement by spring sowing in the forest is possible, and it is desirable to sow in early spring.