Relationships among arbuscular mycorrhizas, root morphology and seedling growth of tropical native woody species in southern Brazil

• Published in: Journal of tropical ecology 2005-09, Vol.21 (5), p.529-540
• Main Authors: Zangaro, Waldemar, Nishidate, Fabio Rodrigo, Camargo, Flavia Regina Spago, Romagnoli, Graziela Gorete, Vandressen, Julia
• Format: Article
• Language: English
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; arbuscular mycorrhizal fungi; Biological and medical sciences; Colonization; ecological succession; ecological successional groups; fine roots; Forest soils; forest succession; Fundamental and applied biological sciences. Psychology; Fungi; Greenhouses; Indigenous species; Microbial colonization; Mycology; Mycorrhizal fungi; native woody species; Plant roots; Plants; root colonization; root hair; Root hairs; root systems; root traits; Roots; seed mass; seedling growth; Seedlings; Soil fungi; succession; Synecology; Terrestrial ecosystems; tropical forest; tropical forests; vesicular arbuscular mycorrhizae; woody plants
• ISSN: 0266-4674; 1469-7831
• DOI: 10.1017/S0266467405002555

The relationships between arbuscular mycorrhizal fungi and root morphological characteristics were studied under greenhouse conditions of 78 tropical native woody species and 47 seedling species collected in the field. Seedlings of native woody pioneer and early secondary species that generally exhibited fine roots with a dense cover of long root hairs showed higher mycorrhizal response and root mycorrhizal colonization than late-secondary and climax species with coarse roots with a sparse cover of short root hairs. Root-hair length and incidence decreased with the progression among the successional groups while fine-root diameter increased, both in the greenhouse and in the field. The mycorrhizal response was highly correlated to root mycorrhizal colonization in the greenhouse and in the field. These parameters were inversely correlated with the seed mass and fine-root diameter, but directly correlated with root-hair incidence, both in the greenhouse and in the field. Mycorrhizal response and root mycorrhizal colonization were also directly correlated with the root-hair length and root/shoot ratio of uninoculated plants. The seedling mycorrhizal status of the early successional woody species suggests that the root traits of these fast-growing species can be more receptive to attraction, infection and colonization by arbuscular mycorrhizas than root traits of late-successional species.