Interactions between Trichoderma pseudokoningii strains and the arbuscular mycorrhizal fungi Glomus mosseae and Gigaspora rosea

Abstract

The interaction between Trichoderma pseudokoningii (Rifai) 511, 2212, 741A, 741B and 453 and the arbuscular mycorrhizal fungi Glomus mosseae (Nicol. & Gerd.) Gerdemann & Trappe BEG12 and Gigaspora rosea Nicolson & Schenck BEG9 were studied in vitro and in greenhouse experiments. All T. pseudokoningii strains inhibited the germination of G. mosseae and Gi. rosea except the strain 453, which did not affect the germination of Gi. rosea. Soluble exudates and volatile substances produced by all T. pseudokoningii strains inhibited the spore germination of G. mosseae. The germination of Gi. rosea spores was inhibited by the soluble exudates produced by T. pseudokoningii 2212 and 511, whereas T. pseudokoningii 714A and 714B inhibited the germination of Gi. rosea spores by the production of volatile substances. The strains of T. pseudokoningii did not affect dry matter and percentage of root length colonization of soybean inoculated with G. mosseae, except T. pseudokoningii 2212, which inhibited both parameters. However, all T. pseudokoningii strains decreased the shoot dry matter and the percentage of AM root length colonization of soybean inoculated with Gi. rosea. The saprotrophic fungi tested seem to affect AM colonization of root by effects on the presymbiotic phase of the AM fungi. No influence of AM fungi on the number of CFUs of T. pseudokoningii was found. The effect of saprotrophic fungi on AM fungal development and function varied with the strain of the saprotrophic species tested.

Mycorrhizal occurrence and responsiveness of tall fescue and wheatgrass are affected by the source of phosphorus fertilizer and fungal inoculation

“…Following studies indicated that mycorrhizal fungal species could be affected and differ in their effect on the bacterial and fungal community composition in the rhizosphere (Paulitz and Linderman 1989;Pfleger and Linderman 1996;Godeas et al 1999;Marschner et al 2001;Gaspar et al 2002;Jeffries et al 2003;Marschner and Baumann 2003). Martı´nez et al (2004) repoted that Trichoderma pseudokoningii inhibited the germination …”

Identifying Beneficial Qualities of Trichoderma parareesei for Plants

“…Both species are cellulolytic and xylanolytic and are grouped with a third sister species, Trichoderma gracile, to form an independent clade within the major Longibrachiatum clade of Hypocrea/Trichoderma, which also includes a close clade with the facultative opportunistic human pathogens Hypocrea orientalis and Trichoderma longibrachiatum (23). Trichoderma pseudokoningii is another interesting species within the clade Longibrachiatum with the ability to inhibit mycorrhizal spore germination (24), produce peptaibols able to induce defense responses in plants (25), and trigger apoptosis in phytopathogenic fungi (26). Compared to species belonging to other clades of Hypocrea/ Trichoderma, with proven biocontrol abilities and beneficial effects on plants (27), neither T. reesei nor T. parareesei has been considered relevant for biocontrol, although the mycoparasitic ability of T. parareesei has recently been demonstrated (21).…”

Management Options for an Efficient Utilization of Phosphorus in Agroecosystems

“…Bacterial inoculants added to promote the plant growth also affect the AMF. Usually positive synergistic effects were observed (Martinez et al 2004).…”