ECM fungi, which usually form dense mantles and forage large areas of soil, can greatly affect the amount of nutrients accessible for other microorganisms (Gadgil and Gadgil 1971, 1975; Pérez-Moreno and Read 2000). Since a large amount of nitrogen is necessary for germination of Trichoderma spp. conidia (Domsch et al. 1980), the inhibitory effect of the mantle hyphae of L. laccata on germination of T. harzianum conidia may be related to competition for resources that were in short supply for both fungi. Though the outcome of the mycelial interactions in vitro suggests different parasitic abilities of L. laccata towards soil fungi, to assess the contribution of
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mycoparasitism of ECM fungi in nutrition of trees in environments poor in N and P, further studies on nutrient flux assessment to mycorrhizal mycelium are required.