ABSTRACT Thermally modified wood undergoes chemical, physical, and mechanical modifications, resulting in changes in resistance to wood biodegrading agents. The objective of this study was to evaluate the resistance to biodeterioration of thermally modified wood by the industrial process VAP HolzSysteme® of Eucalyptus grandis, Pinus taeda and Tectona grandis, submitted to the Lentinula edodes fungi (brown rot) and Pleurotus djamor fungi (white rot), and to analyze the chemical properties, contents of holocellulose, lignin, total extracts, and ash, before and after biodeterioration. Three treatments were considered for each species: Control - wood in natura, modified wood at 140 °C and 160 °C. The specimens were made according to ASTM D 1413 (ASTM, 1994), in a total of 108 samples per species, 36 per treatment for each species, with 12 samples submitted to the fungus L. edodes, 12 to P. djamor and 12 correction blocks. Different behaviors occurred among species under fungal action. For E. grandis wood the thermal modification increased the resistance to biodeterioration of the wood under the action of the L. edodes fungus, in the opposite way occurred for the species P. taeda. There was little variation between treatments in T. grandis wood for both fungi. Thermal modification conferred chemical alterations on the wood, influencing their behavior the biodeterioration by the fungal action in P. taeda species in a negative way, (increasing the degradation level), and E. grandis in a positive way, reducing the biodeterioration. However, in T. grandis species no significant differences were identified in the different treatments by the action of different rotting fungi.

ABSTRACT Plants can stablish symbiosis with arburcular mycorrhiza fungi (AMF), in which the fungus uses carbohydrates synthesized by plant photosynthesis in exchange for soil nutrients. AMF symbiosis may benefit plants by increasing the rates of nutrient uptake, tolerance to abiotic stresses, protection against pathogens and, by promoting resilience of forest species to adverse conditions. Knowledge about the diversity of mycorrhizas may help stablish relationships of species selection, AMF production and inoculation. Therefore, the objective of this review is to compile information to identify existing patterns in AMF diversity in Brazilian forest ecosystems. Compilation was based in 74 articles (in English, Portuguese and Spanish languages) searched in the Web of Knowledge and selected for having the keywords “forest”, “diversity”, “mycorrhizal” and “Brazil”, and that identified AMF species by spore morphology. Compilation resulted in a list of 164 AMF species and indicated that AMF species are not plant host specific but they are selected by environmental conditions where the host grows. Some AMF species were ubiquitous and some were rare in forest ecosystems. Rare AMF species may be an artefact of AMF identification because, in comparison to molecular tools, spore morphology may underestimate AMF diversity. Four AMF species, Acaulospora scrobiculata, Acaulospora foveata, Clareoideglomus etunicatum and Glomus macrocarpum, were ubiquitous to several biomes, existed in different stage of forest succession and seemed to be adapted to different forest managements. Therefore, A. scrobiculata, A. foveata, A. mellea, C. etunicatum and G. macrocarpum could have potential to be used as AMF inoculant in forest species.

RESUMO A espécie australiana Melaleuca alternifolia Cheel., tem uma forte importância na indústria farmacêutica e de cosméticos devido a extração dos óleos essenciais presentes nas folhas. Visando um sistema eficiente de produção de mudas de M. alternifolia, avaliou-se a técnica de miniestaquia e manejo do minijardim clonal na produtividade e enraizamento de miniestacas, além das diferentes composições de substratos nas quatro estações do ano. Minicepas provenientes de mudas propagadas por estaquia foram analisadas durante as quatro estações do ano (setembro/2013 a agosto/2014). A partir das brotações das minicepas foram produzidas miniestacas, as quais foram plantadas em tubetes e mantidas em casa de vegetação por 45 dias. Foram seis os substratos utilizados para o plantio das miniestacas: substrato comercial (S1); substrato composto por 100% de casca de arroz carbonizada (CRH) (S2); substrato composto por 100% de fibra de coco (CF) (S3); substrato composto por 50% CF e 50% CRH (S4); substrato composto por 30% CF e 70% CRH (S5); substrato composto por 70% CF e 30% CRH (S6). A elevada sobrevivência das minicepas (superior a 90%) e produção de miniestacas (282 miniestacas.m-2.mês) em casa de sombra demonstram a viabilidade da técnica para a espécie, sendo o verão a época mais adequada para coleta de propágulos. O substrato a base de 70% CF + 30% CRH (S6) apresenta resultados superiores para a propagação vegetativa de M. alternifolia (91,7% de estacas enraizadas), sendo o único a atender simultaneamente todos os parâmetros avaliados. Recomenda-se o verão como a melhor época para enraizamento das miniestacas.

ABSTRACT The Australian species Melaleuca alternifolia Cheel. has a strong commercial importance due to the extraction of essential oils from its leaves used in the cosmetic and pharmaceutical industry. In order to obtain an efficient plant production system of M. alternifolia the mini-cuttings technique and the clonal mini-garden management in the productivity and rooting of mini-cuttings and different substrate compositions were analyzed during all the seasons. Mini-stumps derived from cuttings and grown in pots (2 L), were submitted to successive harvesting of their sprouts during the four seasons (september/2013 to august/2014). From the mini-stumps sprouts mini-cuttings were produced, wich were were planted in plastic tubes and kept in a greenhouse for 45 days. Six substrates were used for planting the mini-cuttings: commercial substrate (S1); substrate composed of 100% carbonized rice husk (CRH) (S2); substrate composed of 100% coconut fiber (CF) (S3); substrate composed of 50% CF and 50% CRH (S4); substrate composed of 30% CF and 70% CRH (S5); substrate composed of 70% FC and 30% CRH (S6). The high survival of mini-stumps (over 90%) and the mini-cuttings production (282 mini-cuttings.m-2.month-1) in the shade house demonstrate the technical feasibility for the species, being summer the most appropriate time to collect propagules. The substrate composed by 70% CF + 30% CRH (S6) shows superior results for vegetative propagation of M. alternifolia (91.7% of rooted mini-cuttings), as the single one to contemplate simultaneously all parameters. Summer is recommended as the best time for rooting of mini-cuttings.

RESUMO Este artigo apresenta uma revisão sobre as micorrizas e aspectos relacionados com seu uso em espécies florestais e na biorremediação. As informações obtidas na literatura já comprovaram que os fungos ectomicorrízicos podem ser muito importantes no estímulo ao crescimento de mudas e árvores. Quanto à biorremediação, estes fungos são promissores na capacidade de degradar poluentes em solos contaminados. Nesse sentido, são apresentados os benefícios e usos destes microrganismos e as características das ectomicorrizas (ECM), que são promissoras para uso nestes processos. Apresentam-se informações sobre o uso potencial de ECM para a remediação de poluentes orgânicos persistentes e de metais pesados, bem como alguns resultados já pesquisados. Demonstra-se que, internacionalmente, o enfoque das pesquisas sobre micorrizas tem se dado com novas perspectivas, além do uso convencional para o favorecimento do crescimento das plantas.

ABSTRACT This article presents an overview of the aspects of mycorrhizas and their use in forest species and bioremediation. The information gathered from the literature had already indicated that ectomycorrhizal fungi may be very important to stimulate the growth of seedlings and trees. As for bioremediation, these fungi are promising in the ability to degrade pollutants in contaminated soils. In this sense, the benefits and uses of these microorganisms, and the characteristics of ectomycorrhizae (ECM) are presented herein, which are promising for use in these processes. Also, information on the potential use of ECM for the remediation of persistent organic pollutants and heavy metals is presented, as well as some results already searched. It is shown that internationally, the focus of the research on mycorrhizae has occurred with new perspectives, beyond the conventional use to stimulate plant growth.