Influence of the ectomycorrhizal fungus Laccaria laccata on pre-emergence, post-emergence and late damping-off by Fusarium moniliforme and F. oxysporum on Scots pine seedlings

• Published in: Symbiosis (Philadelphia, Pa.) Vol. 42; no. 3; pp. 153 - 160
• Main Authors: MACHON, Paula, SANTAMARIA, Oscar, PAJARES, Juan Alberto, ALVES-SANTOS, Fernando Manuel, DIEZ, Julio Javier
• Format: Journal Article
• Language: English
• Published: Philadelphia, PA Balaban 2006; Rehovot
• Subjects: Biological and medical sciences; Fundamental and applied biological sciences. Psychology; Fusarium; Fusarium moniliforme; Laccaria laccata; Microbiology; Miscellaneous; Mycology; Pinus sylvestris; Forest nursery; Plant pathogen; Microbiology; Biological control; Basidiomycetes; Pinus sylvestris; Nursery; Spores; Fungi; Softwood forest tree; Gymnospermae; Ectomycorrhiza; Fungi Imperfecti; Fusarium moniliforme; Thallophyta; Symbiosis; Fusarium oxysporum; Root; Germination; Symbiont; Seedlings; Treatment; damping-of Fusarium oxysporum; Mycorrhiza; Coniferales; Spermatophyta; ectomycorrhiza. Laccaria laccata
• ISSN: 0334-5114; 1878-7665

The role of the ectomycorrhizal (ECM) fungus Laccaria laccata a biological control agent against pre-emergence, post-emergence and late damping-off caused by Fusarium moniliforme (Fo) and F. oxysporum (Fm) on Scots pine was studied in greenhouse experiments. The vegetative mycelium of L. laccata in a vermiculite/peat carrier was added to potting substrate before inoculation with Fo or Fm spores. Seedlings were also inoculated only with ECM, Fo, Fm or water in order to compare treatments. F. oxysporum did not reduce germination when L. laccata was previously inoculated. Eighteen weeks after sowing, inoculation with L. laccata significantly reduced the damage caused by F. moniliforme, as seen in post-emergence assays, but no reduction of disease symptoms was observed for F. oxysporum. Significant late damping-off damage on Scots pine seedlings was only caused by F. oxysporum. L. laccata did not reduce disease expression in F. oxysporum treatments. Root colonization of seedlings by L. laccata was 51.8% and 26.8% for seed and seedling treatments, respectively. Mycorrhizal formation was significantly lower in plants treated with F. moniliforme or F. oxysporum. It is shown that the protective effect of L. laccata against the damping-off caused by Fusarium spp. in Scots pine seedlings varied among pre-emergence, post-emergence and late damping-off stages.