INFLUENCE OF FIRE ON THE POPULATION OF ARBUSCULAR MYCORRHIZAL FUNGI IN CERRADO STRICTO SENSU

Resumo

IN NOVEMBER 2017, THE CHAPADA DOS VEADEIROS NATIONAL PARK SUFFERED THE GREATEST FIRE IN ITS HISTORY. THE STRICTO SENSU CERRADO IS CHARACTERIZED BY THE PRESENCE OF LOW, SLOPING, TORTUOUS TREES WITH IRREGULAR AND TWISTED BRANCHES, AND USUALLY WITH EVIDENCES OF FIRES. THE OBJECTIVE OF THIS WORK WAS TO EVALUATE THE INFLUENCE OF FIRE IN THE NATIONAL PARK OF CHAPADA DOS VEADEIROS ON SPORE DENSITY, MYCORRHIZAL COLONIZATION RATE AND DIVERSITY OF ARBUSCULAR MYCORRHIZAL FUNGI (AMF) . THE EXPERIMENTAL DESIGN WAS COMPLETELY RANDOMIZED WITH TWO TREATMENTS, WITH AND WITHOUT BURNING, AND SIX REPLICATIONS. SAMPLES OF RHIZOSPHERIC SOIL FROM CERRADO AREAS, REACHED AND NOT REACHED BY FIRE, WERE COLLECTED 15 DAYS AFTER OCCURRENCE OF FIRE IN NOVEMBER 2017. THE SPORES OF AMF WERE EXTRACTED FROM 500 CM�³ SOIL BY THE WET SIEVING TECHNIQUE. IN ORDER TO DETERMINE THE PERCENTAGE OF COLONIZATION, ROOTS WERE BE CLARIFIED AND STAINED WITH 0.05% TRYPAN BLUE IN LACTOGLYCEROL AND VERIFIED USING THE TECHNIQUE OF QUADRANT INTERSECTIONS. THE IDENTIFICATION OF THE AMF GENERA WAS BASED ON THE MORPHOLOGICAL CHARACTERISTICS COMPARED WITH THE INTERNATIONAL CULTURE COLLECTION OF ARBUSCULAR AND VESICULAR-ARBUSCULAR MYCORRHIZAL FUNGI. THERE WAS NO STATISTICAL DIFFERENCE BETWEEN THE AREAS INVESTIGATED FOR MYCORRHIZAL COLONIZATION RATE AND SPORE DENSITY. THE GENERA ACAULOSPORA, CLAROIDEGLOMUS, DIVERSISPORA, GLOMUS, FUNNELIFORMIS AND GIGASPORA WERE IDENTIFIED IN BOTH AREAS.