Mycorrhizal inoculation and phosphorus fertilization show contrasts on native species of the Brazilian Atlantic Forest and Cerrado

Abstract

ABSTRACT Restoration of degraded sites by using native plants like Plathymenia reticulata Benth. and Melanoxylon brauna Schot. is advisable. However, seedlings of both species, when raised on commercial substrates, may present low survival. This study aimed to evaluate the growth of seedlings under inoculation with arbuscular mycorrhizal fungi (AMF). The seedlings were raised on soil sampled from near an adult plant of the same species. The P. reticulata and M. brauna seedlings were grown with or without the inoculation of a mix of three species of AMF (Rhizophagus clarus, Claroideoglomus etunicatum, and Gigaspora albida), and five doses of P (0, 50, 150, 300, and 450 mg dm-3 of P). All seedlings were inoculated with Bradyrhizobium sp., isolated from each species. After 90 days, P. reticulata inoculated with AMF showed higher growth and nutrient content than those uninoculated, and the maximum plant growth was obtained when received 160 to 280 mg dm-3 of P. On the other hand, no effects of AMF inoculation or phosphate fertilization were observed on M. brauna. For both species, no effect of inoculation was observed on mycorrhizal colonization, and M. brauna, unlike P. reticulata presented a considerable number of nodules. We conclude that inoculation with AMF and P fertilization improves the growth of P. reticulata seedlings but does not promote the growth of M. brauna; presenting the necessity to investigate each species.

Keywords

• Plathymenia reticulata
• Melanoxylon brauna
• AMF
• seedling production
• Bradyrhizobium