• The Plant Pathology Journal
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• v.21 no.3
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• pp.237-243
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• 2005

Resistance inductions on the leaves of cucumber plant by an arbuscular mycorrhiza Glomus intraradices were investigated. In addition, the infection structures were observed at the penetration sites on the leaves of plant inoculated with Colletotrichum orbiculare using a fluorescence microscope. The severity of anthracnose disease caused by Colletotrichum orbiculare was significantly decreased on the leaves of cucumber plant colonized with G intraradices compared with those of non-treated control plants. As a positive control, pre-treatment with DL-3-aminobutyric acid (BABA) caused a remarkable reduction of the disease severity on the pathogen-inoculated leaves. There were no significant differences in the frequency of either germination or appressorium formation of the plant pathogen between mycorrhiza colonized and non-treated plants. It was also the same on the BABA pre-treated plants. However, the frequency of callose formation was significantly high on the leaves of G intraradices colonized plants compared to those of non-treated control plants at 5 days after challenge inoculation. On the leaves of BABA treated plants callose formation was not significantly high than those of non-treated, although the disease severity was more strongly suppressed. It was suggested that the resistance induced by colonization with G. intraradices might be related to the enhancement of callose formation at the penetrate sites on the leaves invaded by the pathogen, whereas resistance by BABA did not.

• Korean Journal of Environment and Ecology
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• v.29 no.1
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• pp.88-94
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• 2015

An investigation was conducted on the effects of arbuscular mycorrhizal fungus, Glomus etunicatum on the formation of soil aggregate and mycorhizal development in the roots of Robinia pseudoacacia seedlings in coal mine tailings and forest soil. G. etunicatum formed mycorrhizas by 35.1 % in coal mine tailings and by 48.9 % in forest soil. Its infection was the typical Arum-type forming inter-cellular hyphae and intra-cellular arbuscules. Ergosterol contents were 3.20 ppm in forest soil and 1.92 ppm in coal mine tailings. The formation of soil aggregate per 50 g pot soil was 19.6 g and 9.5 g in inoculated and noninoculated forest soil and 16.5 g and 11.0 g in inoculated and non-inoculated coal min tailings, respectively. In conclusion, G. etunicatum inoculation increased the formation of soil aggregate both in forest soil and coal mine tailings, but was less effective in the latter.

• Journal of Korean Society of Forest Science
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• v.84 no.3
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• pp.306-318
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• 1995

To investigate the effect of low light intensities and the inoculation of Frankia and/or Alpova diplophloeus on the symbioses development and their host growth, red alder(Alnus rubra Bong.) seedlings were grown in an air - filtered walk - in growth chamber with either $N_2$ - fixing Frankia inoculation or N - fertilization and live or dead spore inoculation of the ectomycorrhizal fungus A. diplophloeus(Zeller & Dodge) Trappe & Smith. When they were 20 weeks old, the seedlings were grown under three levels of light intensities of 680, 320 and $220{\mu}mol/m^2/s$ PPFD(photosynthetic photon flux density) for three weeks. PPFD of 220 significantly decreased the development of A. diplophloeus mycorrhizae and nodules, the rates of $N_2$ - fixation and $CO_2$ exchange, and the growth of tile seedlings. PPFD 320 significantly decreased the $CO_2$ exchange rate only. Frankia inoculation significantly increased mycorrhiza formation and seedling growth. Alpova inoculation significantly increased seedling growth but not nodule development and $N_2$ - fixation. None of the symbionts affected $CO_2$ exchange rates. Frankia was more critical for seedling growth and mycorrhizal development than the mycorrhizal fungus for seedling growth and nodule development.

• Journal of Korean Society of Forest Science
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• v.85 no.1
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• pp.96-106
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• 1996

Red alder(Alnus rubra Bong.) seedlings inoculated with Frankia only or both Frankia and spores of Alpova diplophloeus(Zeller & Dodge) Trappe & Smith were grown in a greenhouse for ten weeks. The ten-week-old seedlings were fertilized with six nitrogen(N) and phosphorus(P) fertility regimes (no fertilization, 10mM $NH_4NO_3$, 50mM $NH_4NO_3$, 5mM $KH_2PO_4$, 10mM $NH_4NO_3+5mM$ $KH_2PO_4$, and 50mM $NH_4NO_3+5mM$ $KH_2PO_4$) three times a week for ten weeks. The higher N-fertilization significantly increased mycorrhiza formation by greenhouse contaminant mycorrhizal fungi, but decreased N-fixation and P concentration in nodule tissues. P-fertilization significantly increased nodule and shoot dry weight, and P concentration in plant tissues. When N was highly fertilized, however, the P-fertilization effect disappeared in nodule P concentration but doubled in leaf P concentration. A. diplophloeus inoculation significantly increased diameter growth and $CO_2$ exchange rate, but decreased leaf dry weight. Our results suggest that the higher N- or P-fertilization affect nitrogenase activity and mycorrhizal development but the effects are changed by their interactions.

• Journal of Korean Society of Forest Science
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• v.86 no.4
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• pp.466-475
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• 1997

I examined arbuscular mycorrhizal(AM) fungus inoculation effects on the seedling growth of Korean ash tree(Fraxinus rhynchophylla Hance), which distributes in fertile mesic soils, under a seven-day watering cycle of water stress and compost-added fertile conditions. Three Korea-native AM fungi were inoculated : an unidentified Glomus species, Gigaspora margarita Becker & Hall and Scutellospora heterogama(Nicol. & Gerd) Walker & Sanders from disturbed forest soils. The effect of AM fungus inoculation on the seedling varied depending upon fungal species and soil conditions. AM formation was 27 to 65% by the Glomus without forming spores, 47 to 74% with about 10 spores per 20g soil by G. margarita and about 65% with 35 spores by S. heterogama. The soil conditions did not affect either AM or spore formation. The Glomus inoculation increased shoot N and P concentrations, but did not affect seedling growth. G. margarita increased shoot N and P, irrespective of soil conditions, in general, but S. heterogama increased N under water stress and Pin the control soil only. These two fungi significantly increased seedling growth in both control and water stress soils. Compost addition increased the growth of non-mycorrhizal seedlings and offset AM fungus inoculation effects. The relative field mycorrhizal dependency(RFMD) of the seedlings was significant only in control and water stress soils by over 40% in G. margarita or S. heterogama AM plants. Under water stress RFMD was the most evident in S. heterogama AM plants. I conclude that some AM fungi such as G, margarita and S. heterogama can broaden the niche of Korean ash seedlings to a water stress or nutrient poor site but less likely to more fertile sites.