Mycorrhizal response and successional status in 80 woody species from south Brazil

Arbuscular mycorrhizal (AM) fungi colonization and response were studied in seedlings of 80 native woody species belonging to different successional groups from the Tibagi River Basin, Parana State, south Brazil. This study includes data from 43 native woody species already published. The results with 80 species did not differ from the results of the 43 species. The experiment was carried out in a greenhouse in plastic bags filled with a mix of subsoil (85%) and sand (15%), inoculated or not with spores of native AM fungi obtained from rhizosphere soil of different native tree species in an area with natural vegetation dominated by woody pioneer species. The successional groups were represented by 16 pioneer, 20 early secondary, 29 late-secondary and 15 climax species. The AM response and colonization in the greenhouse were 5.9 and 4.2 times greater in the early successional species than in the late-successional species, respectively. Seedlings of 49 woody species were collected in the interior under the canopy of the tropical forest of the Mata dos Godoy State Park and in a cleared area dominated by woody pioneer species. The percentage of AM colonization in the field was 54.9, 40.4, 7.2 and 3.1 for the pioneer, early secondary, late-secondary and climax species, respectively. The response to AM inoculation was strongly and directly related to AM colonization in the greenhouse and field and inversely related to seed weight. The AM colonization in the greenhouse was strongly and directly related to AM colonization in field. The late-successional species showed lower AM colonization and response than early successional species. The accentuated mycotrophism of the early successional species may be involved in their establishment, growth, survival and early forest structuring on low-fertility soils.