• Journal of the Korean Society of Environmental Restoration Technology
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• v.5 no.2
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• pp.53-62
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• 2002

The objectives of this study were to understand the tolerance mechanism of woody plants to water stress and tolerance changes in relation to mycorrhizal formation. Lespedeza cyrtobotrya Miq. commonly used for erosion control in slopes were raised from seeds and transplanted to 120 plastic pots. Sixty pots received the top soil of a Fraxinus americana forest, while remaining 60 pots received the autoclaved top soil. The forest soil contained 1,200 spores per 100g of arbuscular endomycorrhizal fungus, mostly Glomus sp. The plants were raised outside with regular supply of water and mineral nutrients. Two kinds of water deficit treatment and a control were started at the middle of July : cyclic water deficit treatment with 3 cycles of sequential water stress at the point of xylem water potential of about -0.6, -0.6, and -1.7 MPa and recovery, and non-cyclic water deficit treatment with single water stress at about -1.5 MPa. The non-stressed plants received plenty of water throughout the period. In late August the plants were harvested for measurements of dry weight, N, P, carbohydrate contents, net photosynthesis and superoxide dismutase(SOD) activities. Both cyclic and non-cyclic water deficit treatments reduced dry weight by 60% and 40%, respectively, and reduced nitrogen absorption, while increased SOD activities. Water-stressed plants also showed increased carbohydrate contents in the leaves and lowered stomatal conductance. Mycorrhizal inoculation resulted in an average of 40% infection of roots and 2-3 times increase in P absorption in water-stressed as well as non-stressed plants. Mycorrhizal formation also increased shoot-root ratio. The results that SOD activities of water-stressed plants with mycorrhizal infection were significantly lower than those of non-mycorrhizal plants suggest the possibility of improvement of water-stressed condition by mycorrhizal formation. It was concluded that endomycorrhizal formation increased tolerance of Lespedeza cyrtobotrya seedlings to water stress.

• Korean Journal of Soil Science and Fertilizer
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• v.25 no.1
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• pp.99-107
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• 1992

Effects of the indigenous Vesicular-arbuscular mycurrhizal fungi(VAMF) on early growth response of greenhouse grown crops were experimented. This study was done to evaluate the benefit of indigenous VAMF inoculation on the early growth and the subsequent growth after transplanting of some crops such as cucumber, tomato, hot pepper, eggplant, and melon. Leaf area, shoot dry weight, and plant length of mycorrhizal greenhouse crops showed the tendency of significant or no significant increase over control plants receiving no inoculation. The levels of VA mycorrhizal colonization were increased with plant growth, and infection rates of horticultural crop except hot pepper around one week after transplanting were decreased, while that of 8 weeks after emergence of mycorrhizal seedlings were increased again and infected by around 50% at harvesting time. In spore densities in the rhizosphere soil of craps experimented, the number of spore ranged from $72.7{\pm}26.3$ to $100{\pm}10.3g^1$ on dried soil basis and high density showed in both cucumber and tomato. Total nitrogen contents in shoots were lower in the mycorrhizal plants than non-mycorrhizal one, whereas P uptake in mycorrhizal hot pepper and tomato were highly ramarkable. The K contents in the shoots of mycorrhizal cucumber and eggplent were highly enhanced. Inoculation of the indigenous VAMF enhanced shoot Ca and Mg in both tomoto and melon. The contents of Fe, Zn, Mn and Cu in shoots of mycorrhizal crops were higher than non-mycorrhizal plants and vice versa in case of eggplent. Inoculation of the indigenous VAMF to horticultural crops were effective for alleviation of transplanting shock, and pretransplanting infection improved subsequent growth by reducing the time required for establishment of a functional mycorrhizal symbiosis following transplanting.

• Journal of Korean Society of Forest Science
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• v.90 no.6
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• pp.767-773
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• 2001

We investigated the impacts of the fairy-ring of Tricholoma matsutake on the dynamics of soil microflora and soil enzyme activities by grouping the soils around the fairy-ring of T. matsutake into four regions. The regions were grouped as 'zone of decayed mycorrhizae', 'zone of mycorrhizae for fruiting', 'zone of physiologically active mycorrhizae' and 'zone free from mycorrhizal infection'. Soil fungi and actinomycetes were quite little at the soils around the fairy-ring of T. matsutake compared to those of general forest soils, and there were significant differences among the four regions. The soils with the mycelial cluster of T. matsutake showed about one third of microbial population compared to those in the zone free from mycorrhizal infection, which indicated that T. matsutake took a dominant position within the fairy-ring of the fungus. We could manifest that T. matsutake showed a distinctive characteristics of mycorrhizal fungus since the activities of dehydrogenase were significantly different between the zone of physiologically active mycorrhizae and the zone free from mycorrhizal infection. The dehydrogenase activity was the highest at the early season of fruiting around the fairy-ring of T. matsutake, while the acid-phosphatase activity increased from March to June followed by a slight decrease on August and peaked on October. This phenomenon made us infer that the vitality of T. matsutake be sustained after fruiting.

• Korean Journal of Soil Science and Fertilizer
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• v.37 no.5
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• pp.341-349
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• 2004

This study was conducted to compare the effects of arbuscular mycorrhizal fungi (AMF) on the growth and fruit yield of hydroponically grown cucumber and tomato plants in solid medium culture. Mycorrhizal fungus Glomus sp. was collected from plastic film house soils of cucumber and tomato and inoculated to the experimental crops at the time of seeding and transplanting. Root infection of cucumber and tomato plants by AMF was more significantly increased when the AMF was inoculated at seeding stage than at transplanting stage. In the infected roots of cucumber and tomato, mycorrhizal hyphae was easily observed but vesicle and arbuscule were rare. Overall plant growth was increased with AMF inoculation and the growth was higher when AMF was inoculated at seeding stage. Fresh weight of each fruit of cucumber and tomato and sugar content in tomato fruits were significantly increased with AMF inoculation at seeding stage. The AMF inoculation also increased fruit yields of cucumber and tomato.

• Microbiology and Biotechnology Letters
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• v.21 no.2
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• pp.95-100
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• 1993

Effect of dual inoculation with vesicular-arbuscular(VA) mycorrhizal fungi, Glomus mosseae, and Rhizobium meliloti R455 on growth, nodulation, and nitrogenase activity of alfalfa (Medicago sativa L. cv. Vernal) were examined in pot experiment. After 63 days growth, shoot length, number of leaf, and leaf size of alfalfa were increased as as result of dual inoculation with Glomus mosseae and Rhizobium meliloti. Total dry weight of alfalfa plant was increased 1.4 times compared to single inoculation with Rhizobium meliloti. Nodule number and mean fresh weight of nodule per plant were also increased due to the mycorrhizal infection.

• Journal of Korean Society of Forest Science
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• v.79 no.3
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• pp.309-315
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• 1990

This study was carried out to observe the effects of two soil mixtures, various nitrogen levels, and inoculation with mycorrhizal fungi on the growth of 1-year-old Pinus thunbergil seedlings in pots. The seedlings were treated with various combinations of above factors and grown one more year in pots. 1. Number of short roots, mycorrhizal short roots, height growth, and total dry weight were higher in vermiculite than in sandy loam. 2. 2-year-old P. thunbergii seedlings inoculated with Pisolithus tinctorius mycorrhizal fungi showed significant increase in primary lateral roots, short roots, and total dry weight than those of uninoculated seedlings. 3. The growth of 2-year-old P. thunbergii seedlings was affected by infection with mycorrhizal fungi and nitrogen fertilization of precious year.

• Journal of Microbiology and Biotechnology
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• v.14 no.3
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• pp.553-562
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• 2004

To investigate protective activity in pepper plants, which were pre-inoculated with arbuscular mycorrhizal (AM) fungi Glomus intra radices (Gi), against pathogenic strain Phytophthora capsici (Pc), pathogenesis-related (PR) proteins and antioxidant enzymes were examined. The growth of root and shoot was the highest in peppers inoculated with G. intraradices, compared with non-inoculated control plants and those challenged by the pathogen with and without mycorrhizae after nine days of infection. Mycorrhizal colonization rate was reduced by about 10% in pathogen-challenged plants, but disease pressure was reduced. The activities of PR proteins, $\beta$-1- 3-glucanase and chitinase, were increased in Pc-treated plants compared to Gi+Pc-treated plants in leaves, but those in roots were suppressed. Superoxide dismutase activity and $H_2O_2${/TEX> content in Gi+Pc and Pc-treated plants were gradually increased in leaves. However, those in roots continuously increased up to 5 days, and then decreased dramatically. Peroxidase activity in leaves and roots increased after P. capsici infection both in plants inoculated with or without G. intraradices. These results suggest that AM fungi, G. intra radices, potentially act as one of the protective agents against plant pathogens. Changes of PR proteins and antioxidative enzymes in mycorrhizae-inoculated pepper appear to be regulated differently in leaves and roots by pathogen infection.

• Journal of Korean Society of Forest Science
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• v.77 no.4
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• pp.453-459
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• 1988

The purposes of this study were to evaluate the effects of acid rain on tree growth and on the mycorrhizal formation and the effects of mycorrhizae on the host tolerance to acid rain. Simulated acid rain was applied for five months to Pinus $rigida{\times}taeda$ seedlings in pots inoculated with Pisolithus tinctorius (Pt) and Suillus luteus (Sl). Mycelial inocula of Pt and Sl were either mixed with entire pot soil (Mix) or casted as a band (Band) after soil sterilization. Three pH levels of acid rain (pH 3.0, 4.5 and 6.4 adjusted by 3 : 1 mixture of sulfuric and nitric acids) were tested. Pt-Mix was most effective in growth stimulation and resulted in 45-90% increase in tree height in sandy loam. Pt-Band was less effective than Pt-Mix in growth stimulation and mycorrhizal formation. Simulated acid rain at pH 4.5 stimulated height growth by 10-55%, while acid rain at pH 3.0 did not significantly affect the height growth. The top/root ratio was increased by pH 4.5 treatment, while pH 3.0 treatment reduced it. Mycorrhizal infection rate was not affected by acid rain. Pt inoculation reduced acid-induced leaf injury by 28-58% in both pH 3.0 and 4.5 compared with un-inoculated plants. Sl was also effective in growth enhancement, but was less effective than Pt in both mycorrhizal infection and reducing leaf injury.

• Mycobiology
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• v.33 no.1
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• pp.51-60
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• 2005

Pot greenhouse experiments were carried out to attempt to increase the salinity tolerance of one of the most popular legume of the world; cowpea; by using dual inoculation of an Am fungus Glomus clarum and a nitrogen-fixer Azospirillum brasilense. The effect of these beneficial microbes, as single- or dual inoculation-treatments, was assessed in sterilized loamy sand soil at five NaCl levels ($0.0{\sim}7.\;2ds/m$) in irrigating water. The results of this study revealed that percentage of mycorrhizal infection, plant height, dry weight, nodule number, protein content, nitrogenase and phosphatase activities, as well as nutrient elements N, P, K, Ca, Mg were significantly decreased by increasing salinity level in non-mycorrhized plants in absence of NFB. Plants inoculated with NFB showed higher nodule numbers, protein content, nitrogen concentration and nitrogenase activities than those of non-inoculated at all salinity levels. Mycorrhized plants exhibited better improvement in all measurements than that of non-mycorrhized ones at all salinity levels, especially, in the presence of NFB. The concentration of $Na^+$ was significantly accumulated in cowpea plants by rising salinity except in shoots of mycorrhizal plants which had $K^+/Na^+$ ratios higher than other treatments. This study indicated that dual inoculation with Am fungi and N-fixer Azospirillum can support both needs for N and P, excess of NaCl and will be useful in terms of soil recovery in saline area.

• Microbiology and Biotechnology Letters
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• v.19 no.6
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• pp.548-552
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• 1991

The effect of dual inoculation with vesicular-arbuscular (VA) mycorrhizal fungi, Glomus mosseae, and Bradyrhizobium sp. R938 on the nitrogenase activity of peanut plant (Arachis hypogeae L. cv. Youngho) was studied in pot experiment. As a result of the dual inoculation with Glomus mosseae and Bradyrhizobium on peanut plant, nitrogenase activity was increased by 1.5 times compared with single inoculation with Bradyrhizobium sp. R938. After 69 days growth of peanut plant, the size of nodules was also increased due to the mycorrhizal infection. The mean fresh weight per nodule was 6.7 mg in treatment with the dual inoculation, which is the 1.5 times increase compared with single inoculation with Bradyrhizobium sp. R938. These results suggested that there might be a hormonal effect of VA mycorrhizal fungi in addition to the effect of increase in nitrogen fixing ability through the enhancement of nutrient absorption.