• Journal of The Korean Society of Grassland and Forage Science
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• v.31 no.3
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• pp.269-276
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• 2011

To investigate the physiological effects of mycorrhizal colonization on drought stress tolerance in white clover, the responses of leaf water potential (${\Psi}_{PL}$), relative water content (RWC), leaf dry mass, photosynthesis rate, transpiration, stomatal conductance, proline and ammonia were assessed periodically during 7 days in non-AM and AM plants under wellwatered or drought-stressed conditions. Under well-watered conditions, the examined parameters were not significantly changed or very little affected by AM symbiosis. Drought decreased water potential, relative water content, photosynthesis rate, transpiration and stomatal con ductance by 68.6%, 22.7%, 97.7%, 83.9% and 84.9%, respectively, in non-AM plants, meanwhile 46.8%, 13.4%, 50.3%, 44.8% and 54.7%, respectively, in AM plants. In addition, drought increased ammonia and proline by 31.8% and 162%, respectively, in non-AM plants, while 20.9% and 76.9%, respectively, in AM plants. These results clearly showed that mycorrhizal colonization significantly relieved the responses of physiological parameters to drought stress in white clover.

• 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.