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Native or exotic arbuscular mycorrhizal fungi on angico and brauna seedlings

Fungos micorrízicos arbusculares nativos ou exóticos em mudas de angico e braúna

ABSTRACT

This study aimed to assess the growth and mycorrhization of greenhouse-grown angico (Anadenanthera peregrina (Vell.) Brenan) and brauna (Melanoxylon brauna Schott) seedlings based on inoculation with a community of selected or field-collected arbuscular mycorrhizal fungi (AMF), in formulated and commercial substrate. Each species corresponded to one experiment, conducted in a completely randomized design and 2x4 factorial scheme, consisting of two substrates, four inoculation treatments and four repetitions of 12 seedlings each, totaling 384 seedlings per experiment. The substrates used were: DAR – mixture of 30% organic compost, 30% subsoil (clay), 30% sandy soil and 10% rock phosphate; and CS - commercial substrate consisting of expanded vermiculite, peat, charcoal, macro and micronutrients; and four treatments: T1 - control; T2 – fertilized control; T3 – mixture of selected fungi; and T4 – mixture of native fungi. At 100 days after sowing (DAS) for angico and 180 DAS for brauna, seedling height and diameter were measured and leaf area (LA), shoot (SDW) and root dry weight (RDW), number of AMF spores and mycorrhizal colonization were determined. Angico seedlings grown in DAR obtained the highest diameter, height, SDW, RDW and LA values, as well as greater inoculation efficiency, LA, RDW, as well as greater inoculation efficiency and sporulation in this substrate. In both substrates, inoculated angico seedlings were taller and had a larger LA than their noninoculated counterparts. In brauna, the type of substrate only influenced seedling diameter, with DAR promoting greater growth. In DAR substrate, inoculation with selected AMF (T3) resulted in greater seedling height and diameter. In CS, all the seedlings produced in T2 (fertilized and noninoculated) died, whereas the inoculation treatments increased LA, SDW and RDW. It is recommended that angico seedlings grown in DAR be inoculated with native AMF collected in the field. For brauna, further research is needed using other production techniques combined with AMF inoculation.

Keywords
On farm inoculation; Anadenanthera peregrina ; Melanoxylon brauna ; Mycorrhiza

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