BIODIVERSIDADE DE FUNGOS MICORRÍZICOS ARBUSCULARES SOB SOLO DE CERRADO

Abstract

The Cerrado is a biome whose main floristic characteristic is a diversity of phytophysiognomies made up of landscapes that range from dense tropical forests to areas of undergrowth and sparsely dense tree species. The cerrado can be classified according to five phytophysiognomies, which differ according to the visual characteristics of the landscape, these phytophysiognomies are Campo Limpo, Campo sujo, Cerradão, Strictu sensu and Veredas. Understanding the dynamics of mycorrhizal fungi in the Cerrado is essential to adopt conservation practices and to understand the resilience of this biome in relation to adverse situations. Therefore, this work aims to verify the dynamics of the mycorrhizal population in the five phytophysiognomies of the Cerrado biome. Thus, the objective of this work was to evaluate the mycorrhizal activity in agroecosystems under Cerrado soil. Three experiments were carried out, here divided into three chapters. The first proposed to evaluate mycorrhizal activity in forage grasses in cerrado soil. The second was to assess the biodiversity and mycorrhizal activity in buriti, cerrado cashew and pequi and the third was to assess the mycorrhizal activity and biodiversity in soils of different cerrado phytophysiognomies in the region of the são patricio valley. In experiment 1, there were no differences in spore density in the rhizosphere of the studied plants; The forage Brachiaria decumbens had the highest rate of mycorrhizal colonization while Megathyrsus maximum cv. Mombasa had the lowest ecstatic value. The identified mycorrhizal fungi genera are commonly found in the rhizosphere in all investigated grasses, except for the genera Gigaspora, Scutelospora and Sclerocysts, which indicates that the association with these fungus genera is less recurrent than with the others. In experiment 2, there was no statistical difference between the values of spore density and mycorrhizal colonization rate in the three investigated species. The genera Acaulospora, Claroideglomus, Diversispora, Scutellospora, Sclerocystis, Glomus, Funneliformis, Gigaspora, Ambispora and Scrobiculata were identified in the rhizosphere of pequi, cerrado cashew and buriti. Except for Scrobiculata and Scutellospora, all other genera are commonly found in Buriti. In cerrado cashew the genera Funneliformis, Sclerosystis and Scutellospora show less affinity. In the pequi rhizosphere, only the genus Gigaspora has low affinity with the plant. In experiment 3, there was no statistical difference between the values of spore density and mycorrhizal colonization rate in the investigated phytophysiognomies. The genera Acaulospora, Claroideglomus, Diversispora, Scutellospora, Sclerocystis, Glomus, Funneliformis, Gigaspora, Ambispora and Scrobiculata were identified in the rhizosphere of cerrado plants of the investigated phytophysiognomies. Campo Limpo showed greater affinity with Diversispora and Gigaspora; Campo Sujo with Gigaspora, Glomus and Ambispora; Cerradão, on the other hand, did not show affinity with Sclerovystis and Gigaspora, Strictu Sensu with Scutellospora and Funneliformis and Veredas with Scrobiluata.