Syngonanthus elegans is an endangered plant species occurring in the Brazilian Cerrado whose interaction with arbuscular mycorrhizal fungi (AMF) is poorly understood. The aim of this work was to evaluate the occurrence of AMF species and mycorrhizal colonization of S. elegans in two sampling areas named "Soberbo" stream (Soberbo) and "Parque Nacional das Sempre-Vivas" (Park), both found in Diamantina-MG, Brazil. In each area, one plot (100 x 100 m) was established, and roots and soil samples near the roots were collected from 10 plants in each plot. Further sampling included three specimens each of Loudetiopsis chrysothrix and Xyris sp.. Typical mycorrhizal colonization structures were observed in S. elegans roots, and colonization was measured at 75%. Considering both sites and all three hosts, 26 AMF species were recovered, 8 of which were identified only at the genus level. Glomus sp. 1, Scutellospora pernambucana, Acaulospora cavernata and Acaulospora mellea were classified as dominant in both areas. Other species were also considered dominant, including Glomus sp. 4 in Soberbo and Dentiscutata biornata and Gigaspora albida in Park. Trap cultures revealed the presence of seven additional species. For S. elegans, AMF species richness was slightly higher in Park than in Soberbo. Simpson diversity and evenness were slightly higher in Soberbo for S. elegans-associated AMF communities. Overall, S. elegans is highly colonized by arbuscular mycorrhizal fungi and is associated with a wide range of AMF species in the field, suggesting that this association is important for the establishment and survival of this threatened species. Some of the observed species may be new to science.Index terms: Fungal diversity; star flowers; Rupestrian fields. RESUMOSyngonanthus elegans é uma espécie vegetal em vias de extinção que ocorrem no Cerrado brasileiro, cuja interação com fungos micorrízicos arbusculares (FMA) é deficientemente compreendida. O objetivo deste trabalho foi avaliar a ocorrência de espécies de FMA e colonização micorrízica de S. elegans. Em duas áreas de amostragem denominadas Córrego do Soberbo (Soberbo) e Parque Nacional das Sempre-Vivas (Parque), ambas localizadas em Diamantina-MG, Brasil, uma parcela de 100 x 100 m foi estabelecida e solo da rizosfera e raízes foram coletados de 10 plantas em cada parcela. Além disso, amostragem incluiu três espécimes de cada Loudetiopsis chrysothrix e Xyris sp.. Estruturas típicas de colonização micorrízica foram observadas nas raízes de S. elegans e a colonização medida foi de 75%. Considerando as duas áreas e os três hospedeiros, 26 espécies de FMA foram recuperados, 8 delas identificadas apenas até gênero. Glomus sp. 1, Scutellospora pernambucana, Acaulospora cavernata e Acaulospora mellea foram classificados como dominantes em ambas as áreas. Além dessas, também foram consideradas dominantes Glomus sp. 4 em Soberbo, e Dentiscutata biornata e Gigaspora albida no Parque. Culturas armadilhas revelaram a presença de sete espécies adicionais. Para S. elegans, a rique...

-The benefit promoted by ectomycorrhizal depends on the interaction between symbionts and phosphorus (P) contents. Phosphorus effect on ectomycorrhizal formation and the effectiveness of these in promoting plant growth for fungal pre-selection were assessed under in vitro conditions. For P effect evaluation, Eucalyptus urophylla seedlings inoculated with four Pisolithus sp. isolates and others non-inoculated were grown on substrate containing 0.87, 1.16 and 1.72 mg P per plant. For evaluation of effectiveness and fungal pre-selection, other 30 isolates of Pisolithus sp., Pisolithus microcarpus ITA06 isolate, Amanita muscaria AM16 isolate, Scleroderma areolatum SC129 isolate were studied. D26 isolate promoted the highest plant heights for the three P doses, D51 at the lower dose and D72 at the intermediate dose. P doses did not influenced shoot fresh weight and fungal colonization. In the pre-selection of fungi, 14 isolates of Pisolithus sp., P. microcarpus ITA06 isolate and S. areolatum SC129isolate increased plant height and fresh weight. D82 isolate of Pisolithus sp. had effect singly on plant height while D17 and D58 on fresh weight. Of these, only D15, D17, D58 and ITA06 had typical ectomycorrhizae. The cultivation in vitro has shown adequate for pre-selection of ectomycorrhizal fungi. Colonization and benefits depend on species and isolate. D15, D17 and D58 of Pisolithus sp. and P. microcarpus isolate ITA06 are the most promising for nursery studies.Keywords: Inoculation; Ectomycorrhizal fungi; Controlled mycorrhization. AVALIAÇÃO in vitro DE ECTONICORRIZAS EM EUCALIPTO UTILIZANDO SUBSTRATO COM DOSES DE FÓSFORO PARA PRÉ-SELEÇÃO DE FUNGOS RESUMO -O benefício promovido pelas ectomicorrizas é dependente da interação entre os simbiontes e dos teores de fósforo (P). O efeito do P na formação de ectomicorrizas e a efetividade destas na promoção

Ectomycorrhizae are classified as biotechnology to increase the sustainability of planted forests, and fieldwork is needed to confirm its effectiveness. The growth of rooted cuttings of Eucalyptus clones GG100 and GG680, which had been previously inoculated in the nursery with ectomycorrhizal fungi, was evaluated after planting them in the field. The ectomycorrhizal fungi (EMF) inoculated were: Pisolithus microcarpus, Hysterangium gardneri, or Scleroderma areolatum. Uninoculated rooted cuttings were used as controls. The inoculated treatments and the uninoculated controls (low P control) were grown in a nursery with reduced phosphate fertilization. Additionally, uninoculated controls were grown on a substrate with complete phosphate nursery fertilization (high P control). After two months, the plant height of clone GG100 inoculated with P. microcarpus was 16% taller and of clone GG680 13% higher than the low P control treatment. At the same time, the collar diameter of the plants inoculated with H. gardneri and P. microcarpus was the same as in the high P control. At 12 months, the growth of the inoculated and low P control plants was the same as in the high P control. For ectomycorrhizal colonization, after six months, the mean percentage of colonized root tips was highest in plants inoculated with S. areolatum, followed by those inoculated with P. microcarpus and of the low P control. After one year, ECM colonization was equal in all treatments and 4.3 times greater than it was at 6 months. Inoculation with ECM fungi in the nursery boosts early plant growth after transfer to the field, although the effect depends on the specific ectomycorrhizal fungus and the clone. Further ectomycorrhizal colonization of Eucalyptus occurs naturally and increases with tree development in the field.

-The ectomycorrhizal fungi have different tolerance to herbicides and may promote the survival and growth of the eucalypts tree. This study aimed to evaluate the tolerance of Pisolithus sp. isolates to glyphosate and isoxaflutole. The isolates evaluated were D3, D16, D17, Pt24 and UFVJM04. Glyphosate concentrations were: 0, 32, 63, 127 and 254 mg L -1 in liquid medium; 0, 32, 63, 127, 254, 507 and 1014 mg L -1 in solid medium. For isoxaflutole, the concentrations were 0, 295, 589, 1178 and 2355 mg L -1 for both media. Assays were independent for each herbicide and culture medium. The tolerance of isolates depended on the herbicide and its concentration in each type of culture medium. Pt24 was the most tolerant to glyphosate and the UFVJM04 to isoxaflutole. Glyphosate was more toxic to isolates of Pisolithus than isoxaflutole.Keywords: Herbicide: Ectomycorrhiza: Eucalyptus. 0, 32, 63, 127 e 254 mg L -1 , enquanto no meio sólido, de 0, 32, 63, 127, 254, 507 TOLERÂNCIA DE Pisolithus sp. A GLYPHOSATE E ISOXAFLUTOLE In Vitro RESUMO -Os fungos ectomicorrízicos possuem tolerância diferenciada aos herbicidas e podem promover a sobrevivência e crescimento das plantas de eucalipto. O objetivo deste trabalho foi avaliar a tolerância de isolados do fungo ectomicorrízico Pisolithus sp. aos herbicidas glyphosate e isoxaflutole. Os isolados avaliados foram D3, D16, D17, Pt24 e UFVJM04 e as concentrações de glyphosate no meio líquido, de

The aim of this study was to evaluate the effect of vegetation on soil microbial activity during spontaneous restoration and the effect of remaining eucalypts on the restoration stage of reserve ranges installed in eucalypt plantations. The studied areas were in the following stages: initial restoration stage with and without remaining eucalypts; advanced restoration stage with and without remaining eucalypts. Areas of Cerrado, native forest and commercial eucalypt plantation (Eucalypts) were evaluated for reference. Principal component analysis detected the following groups: 1-Cerrado and areas in initial restoration stage with or without eucalypts and areas in advanced restoration stage without eucalypts; 2-areas in advanced restoration stage with eucalypts; 3-native forest; 4-Eucalypts. The restoration areas are at intermediate stage of recovery, slightly superior to the advanced stage. Basal respiration, organic and microbial soil carbon and microbial and metabolic quotients were more similar to those observed in Cerrado than in eucalypt cultivation areas and little influence of the remaining eucalypts plants was observed.