• Korean Journal of Environment and Ecology
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• v.21 no.6
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• pp.544-553
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• 2007

This study is focused on the cultivation of seedlings and cuttings of roundleaf chastetree(Vitex rotundifolia L. f.) according to the sorts of soil and fertilization methods. The results are summarized as follows: When roundleaf chastetree seedlings(aged 1-0) and cuttings(aged 1-0) were cultivated in three different kinds of soil- sand, granite soil, and yellow silt- without any fertilization, 70% of the seedlings survived in sand and granite soil, and 35% did in yellow silt; 90% of the cuttings survived in granite soil and 80% did in sand and yellow silt. The general growth of both seedlings and cuttings was good in granite soil, and sand but relatively inferior in yellow silt. Seedlings showed good stem growth while cuttings had fine root growth. In case of cultivation of seedlings with different kinds and quantities of fertilizer adjusted and with granite soil as basic soil, seedlings and cuttings survived in the experimental section where only the organic fertilizer was used as basic fertilization; in contrast, seedlings grown in the experimental section were all dead where both inorganic and liquefied fertilizer were used. Cuttings showed considerably higher survival rates than seedlings at the experimental fertilization section; particularly, the survival rate of cuttings was twice as much as that of seedlings at the experimental section with low fertilization. This study results revealed that cuttings are desirable than seedlings in general rootage, growth, adaptability to soil, and cuttings have lower demand for soil fertility in time of growing roundleaf chastetree saplings.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.65 no.4
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• pp.426-435
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• 2020

To determine the damages to waxy corn caused by low temperature weather, we investigated the relationship between the temperature and duration of low temperature treatment and the changes in growth characteristics during the recovery period after the treatments in different growth periods. Growth inhibition started in the low temperature group treated at temperatures below 5℃ for three days. The inhibition ratio (IR) was more than 22% or more in all sample groups. As the treatment duration increased and the Temperature decreased, the growth was more greatly inhibited than that in the control. The IR was the highest at 27% or more in the 2nd leaf stage group treated at below 5℃ for 5 days. The IR was in the order of 2nd leaf stage > 1st leaf stage > coleoptile. The IR during recovery was the highest in the 2nd leaf stage group treated at -3℃ degree for 7 days, nd the values were 82% and 98% for NDVI and Fv/Fm, respectively. Especially, all groups treated at -3℃ showed either no changes or decreases in the growth characteristics. As a result, growth inhibition increased as the temperature decreased, and as the duration of the low temperature increased. The degree of damage was in the order of 2nd leaf stage > 1st leaf stage > coleoptile. All early seedlings stopped growing and withered when exposed to temperatures at or below -3℃ for 3 days or more.

• Research in Plant Disease
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• v.22 no.2
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• pp.100-106
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• 2016

We have studied the mycelia growth of four soil-borne fungal pathogens under light qualities and two lighting types (continuous and intermittent) provided by light-emitting diodes (LEDs). As a result, each mycelia growth on Phytophthora cactorum KACC40166, Athelia rolfsii KACC40170, and Helicobasidium mompa KACC40836 strain showed the similar growth rates within 10% or less difference among treatments compared to dark control, regardless of lighting types. However, the mycelia growth on Rosellinia necatrix KACC40168 strain was significantly suppressed by blue, blue+green and blue+red LED as well as fluorescent lamp compared to a dark control, in common with lighting types. The melanin pigment on R. necatrix KACC40168 strain showed relatively to induce more strongly under green LED and fluorescent lamp, whereas no induction under red LED and a control, regardless of lighting types. Thus, the hypha width on R. necatrix KACC40168 was significantly thinned by blue and blue+green LED compared to a control, in common with lighting types.

• Journal of Korean Society of Forest Science
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• v.103 no.2
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• pp.203-210
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• 2014

The purpose of this study was to investigate the effect of experimental warming using infrared lamps on seed germination and seedling survival rate of Pinus densiflora and Abies holophylla. The air temperature of warmed plots had been automatically maintained 3 higher than control plots. The percent germinations (%) of the two coniferous species were higher in warmed plots than in control plots, however a significant difference appeared only in A. holophylla. In addition, P. densiflora and A. holophylla showed the shorter mean germination time (days), higher germination rate ($seed{\cdot}day^{-1}$) and germination energy (%) in warmed plots than in control plots. A. holophylla showed a higher seedling mortality rate in the warmed plots than in control plots because of increased air and soil temperatures and decreased soil moisture. However, seedling survival rate of P. densiflora showed no significant difference by experimental warming. In the future, changed air and soil temperatures and soil moisture due to global warming will induce a variety of changes in seed germination and survival rate of tree species in nursery culture. Therefore, it is necessary to establish adaptation strategies that improve techniques in nursery culture against global warming.

• Journal of Bio-Environment Control
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• v.19 no.4
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• pp.311-316
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• 2010

This study was conducted to investigate the effect of anaerobic fermentation of wheat bran to prevent root-knot nematodes which are infected in plastic house due to over 10 years continuous cultivation of fruits and vegetables. Anaerobic fermentation treatment of wheat bran was done for 20 days by mixture of 2,000 kg fresh wheat bran per 10 are and soil with water in 30 cm soil depth. Chemical treatment of fosthiazate was done by mixture of 6 kg soil for 7 days. Both treatments show suppression of density of rootknot nematodes, especially in anaerobic fermentation treatment. Anaerobic fermentation treatment keeps the low level of root-knot nematode density until 90 days of cultivation and also showed good effect of melon growth. Related with death percentage of melon plant, anaerobic fermentation treatment shows only 3% and also large size of quality fruit but control 65%. Anaerobic fermentation treatment of wheat bran have proved to control the level of root-knot nematodes instead of synthetic chemicals for at least one cropping season and it showed good effect to fruit quality.

• Korean journal of applied entomology
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• v.10 no.1
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• pp.31-38
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• 1971

Tolerance test in plastic vat, pot and fold tests were carried out to investigate the selective herbicides for soybean culture in sandy loam. The soybean plants showed great tolerance against herbicides such as Tri-allate (Avadex-BW), Alachlor (Lasso), Butachlor (Machete), Propachlor (Ramrod), Nitrofen (TOK), MO, HE-314, Nitrofen/Dinoseb(TOK/DNBP), and Chlo.oxu.on (Tenoran), and the growth was normal even when each was treated with the herbicides up to 2ft3 times of the recommended concentrations. Soybean plants showed a slight tolerance against Prometryne (Gesagard), Propazine (Gegamil), Diuron (Karmex), Metabromuron (Patoran), Linuron (Lorox) and Swep when each was treated with herbicides up to 1-2 times of the recommended concentrations. Great injury or withering was noticed due to the high sensitivity of soybean to Simazine (CAT) and to Floumetron (Cotoran). In pot and field experiments with herbicides such as Butachlor (Machete), Alachlor (Lasso), Nitrofen (TOK), Kerb, Nitrofen/Dinoseb (TOK/DNBP), Swep, Linuron (Lorox), Simazine (CAT) and PCP, the following results were obtained: Great injuries were noticed with Simazine (CAT). Also, Linuron (Lorox) and Kerb showed a slight injury at early growth stage of soybean, Nitrofen (TOK) , Nitrofen/Dinoseb (TOK/DNEP), Alachlo. (Lasso), Butachlo. (Machete) and Swep had high selectivities for soybean and no injury was noticed. With respect to herbicidal effects there was a greatly significant difference between treated plots and non-treated plots with the exception of Simaaine (CAT) plot in field test. E. crusgalli and C. sanguinalis were tolerant against Simazine(CAT) and Linuron(Lorox). Cyperus and E. annuus were tolerant against Kerb. Great herbicidal effects on grasses were observed in Alachlor (Lasso) and Butachlor (Machete) plots. Among broad-leaf weeds, P. hydropiper and C. album were tolerant against Butachlor (Machete) and Alachlor (Lasso). When soybean was treated with the herbicides such as Alachlor (Lasso) (ai. 150g/10a), Butachlor (Machete) (ai. 300g/10a), Nitrofen (TOK) (ai. 250g/10a), Linuron (Lorox) (ai. 75g/10a) once after seeding, no additional wording was required till harvest.

• Research in Plant Disease
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• v.21 no.3
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• pp.215-221
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• 2015

This study was conducted to control ginger rhizome rot treated with the combined treatment, the hairy vetch, carbonized rice husk and eggshell calcium in organic ginger farm. Early symptoms of leaf yellowing and plant wilt began in the chemical fertilizer treatment on July 1. Ginger rhizome rot was more progressed on October 2, and stem browning and dead plant showed a high disease incidence with from 36.7% to 43.0%. On the other hand, the combined treatment did not occur at all until July 1 and delayed the disease incidence to October 2. It showed a low disease incidence of 1.3% to 1.7%. In the combined treatment, the content of soil Na, Fe, Cu was decreased and organic matter was increased twice with 31.6% than previous. Population density of Pythium sp. is lower in the combined treatment ($0.3-2.0{\times}10^3cfu/g$ than the chemical fertilizer treatments ($12.0-12.3{\times}10^3cfu/g$). The combined treatment, hairy vetch, carbonized rice husk and the eggshell calcium is able to control the ginger rhizome rot in organically cultivated ginger field.

• The Korean Journal of Ecology
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• v.26 no.3
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• pp.135-142
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• 2003

Four legume plants showed better growth by the external nitrogen supply rather than the symbiotic nitrogen fixation only under salt additions. In case of Glycine max and Phaseolus angularis, total nitrogen contents decreased by high salinity level but their amino acid levels significantly increased with the increase of salt treatments and indicated high soluble-/insoluble-N ratios. Cassia tora and Albizzia julibrissin contained less amino acids than G. max and P. angularis but total N (esp. insoluble N fraction) increased with higher salt levels. Asparagine occurred as a main amino acid especially in G. max and P. angularis and can be seen as potential N-storage form in these plants. It might be play an important role for the osmoregulation mechanism under the saline condition. Meanwhile, to investigate what kinds of nitrogen sources are effective for overcoming salt stress on soybean plants, various N forms and concentrations (NH₄NO₃-N, NO₃-N, NH₄NO₃-N; 2.5 and 5 mM) were additionally supplied to the salt gradient medium. Soybean plants treated with NH₄NO₃-N showed the best growth up to 40 mM NaCl and NO₃- fed plants indicated good growth even at 80 mM NaCl treatments. Contrary to NH₄NO₃- and NO₃- fed plants, NH₄/sup +/- fed plants showed remarkable growth reduction and died by 40 and 80 mM NaCl treatments after the first harvest (15th day). Consequently, these results suggest that salt excluding and resistant capacities of soybean plants under NaCl treatments are increased in order of NH₄ - N, control, NO₃- N and NH₄NO₃- N depending on N concentration except NH₄- N treatments.

• Journal of The Korean Society of Grassland and Forage Science
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• v.39 no.4
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• pp.216-226
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• 2019

This study was to investigate the effect of the horse grazing intensity on the vegetation of the S. quelpaertensis, and the physiological changes of the horse. This experiment was conducted at the community of the S. quelpaertensis (altitude of 550m) with the grazing intensity of 1.0AU(500kg), 1.5AU(750kg) and 2.0AU(1,000kg) at 30m × 30m for one week, and then the growth characteristics of the S. quelpaertensis, the changes of the vegetation, the damages on trees and the changes in the physiological characteristics of the horses was investigated and compared before and after the horse grazing. As the results, the 2.0AU grazing land showed that the culm number had the inverse correlation (r=-0.902, P<0.01) to the other lands and the species diversity index of lower-level vegetation showed the correlation (r=0.773, P<0.01) as increasing the grazing intensity.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.14 no.4
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• pp.1-10
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• 2011

This study was conducted to compare the growth of Zoysia japonica depending on different soil treatments in Saemangeum sea dike, which is filled with dredged soil. Zoysia japonica was planted using sod-pitching method on the control plot. On plots which were treated with forest soil and soil improvement, Zoysia japonica seeds were sprayed mechanically. Sixteen months after planting, coverage rate, leaf length, leaf width, and root length were measured and analyzed. Also, three Zoysia japonica samples per plot were collected to analyze nutrient contents. Coverage rate was 100% in B treatment plot(dredged soil+$40kg/m^3$ soil improvement+forest soil), in C treatment plots (dredged soil+$60kg/m^3$ soil improvement+forest soil), and D treatment plots (dredged soil+$60kg/m^3$ soil improvement), while only 43% of the soil surface was covered with Zoysia japonica on control plots. The width of the leaf on C treatment plots (3.79mm) was the highest followed by D treatment (3.49mm), B treatment (2.40mm) and control plots (1.97mm). Leaf and root length of D treatment was 30.18cm and 13.18cm, which were highest among different treatments. The leaf length of D treatment was highest followed by C, B, and A treatments. The root length of D treatment was highest followed by C, A, and B treatments. The nitrogen and phosphate contents of the above ground part of Zoysia japonica were highest in C treatment, followed by D, B, and A treatments. The nitrogen and phosphate contents of the underground part of Zoysia japonica were highest in D treatment, followed by C, A, and B treatments. C and D treatments showed the best results in every aspect of grass growth. The results of this study could be used to identify the cost effective way to improve soil quality for soil surface fixation on reclaimed areas using grass species.