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 O objetivo desta pesquisa foi estimar parâmetros genéticos de progênies de Eucalyptus macarthurii e estimar ganhos genéticos por diferentes métodos de seleção. Foram utilizados testes de onze progênies, instalados em 1997 em blocos ao acaso, em dois ambientes, com 5 repetições de 5 plantas por parcela. Os indivíduos foram avaliados desde o primeiro ao oitavo ano, quanto à variável diâmetro à altura do peito. Os parâmetros genéticos foram estimados pela metodologia de modelos mistos (REML/ BLUP). A seleção de progênies para formação de Pomar Clonal de Sementes baseou-se na análise por local, análise conjunta e no método da média harmônica do desempenho relativo dos valores genéticos (MHPRVG) com diferentes intensidades de seleção entre e dentro de famílias: três, quatro, cinco e seis indivíduos por família, com seleção dos 30 melhores indivíduos, considerando-se o tamanho efetivo populacional (N e ). A idade mais indicada para se realizar a seleção foi aos sete anos de idade, porém uma seleção precoce pode ser realizada a partir dos dois anos. As particularidades de cada ambiente influenciaram na expressão fenotípica das progênies, de modo que os maiores ganhos, em equilíbrio com o N e , foram estimados com a seleção dos indivíduos para cada local, sendo a seleção entre cinco e seis indivíduos por progênie.

ABSTRACT The aims of this research was to estimate genetic parameters of Eucalyptus macarthurii progenies and to predict genetic gain for different selection methods. In order to evaluate the gains, eleven progenies tests were studied. These tests were installed in 1997, in randomized blocks design, in two sites, with 5 replicates of five plants per plot. The progenies were evaluated, from the first to the eighth year, regarding the variable diameter at breast height (DBH). The genetic parameters were estimated using the mixed model procedure (REML/BLUP). The selection of the progenies for establishing a Clonal Seed Orchard was based on the analysis by location, joint analysis and on the harmonic mean of the relative performance of genotypic values (HMRPGV) with different selection intensities among and within families: three, four, five and six individuals per progeny with the selection of the top 30 individuals, taking into consideration the effective population size (N e ). The best age to carry out the selection was seven years old, however, early selection can be made from age two onwards. Each environment characteristics influenced progenies phenotypic expression, so the higher gains in balance with N e , were estimated with the selection of individuals for each site, and the selection of five or six individuals per progeny.

Pinus taeda L., a principal espécie florestal plantada no Sul do Brasil, tem sua madeira usada como matéria-prima em serrarias, laminadoras e indústrias de aglomerado, MDF, celulose e papel. Devido à sua grande importância econômica, existe interesse no desenvolvimento de técnicas de propagação vegetativa que permitam a clonagem massal de mudas. O objetivo deste trabalho foi avaliar o efeito da idade das mudas (60, 90, 120 e 150 dias) e das quatro estações do ano no enraizamento de miniestacas de P. taeda. Miniestacas de 5 cm foram confeccionadas a partir de ramos herbáceos e tratadas com solução de Captan® 0,1%. Seu plantio foi realizado em tubetes com substrato Mecplant® na camada inferior e 2 cm de vermiculita na porção superior. As miniestacas foram mantidas em casa de vegetação durante 120 dias, com temperaturas entre 15 e 25 ºC e umidade relativa do ar em torno de 90%. Avaliaram-se as porcentagens de miniestacas enraizadas, sobreviventes e mortas, o comprimento das três maiores raízes e o número e massa seca de raízes formadas por miniestaca. A idade das mudas influenciou o enraizamento, e a maior porcentagem (85%) foi obtida com mudas mais jovens (60 dias). O inverno mostrou-se o período mais favorável para a coleta das miniestacas.

Pinus taeda L. is the main forest tree species planted in Southern Brazil and its wood is used for sawlogs, venner, particle board, medium density fiberboard (MDF), pulp and paper industries. Due to its high economic importance, interest exists in developing techniques for vegetative propagation aiming at mass multiplication. The purpose of the present work was to evaluate the effect of the age of seedlings used as mother plants (60, 90, 120 and 150 day-old) and of the four seasons of the year on rooting of P. taeda minicuttings. Minicuttings of 5 cm in length were collected from herbaceous branches and treated with Captan® solution (0.1%). Minicuttings were planted in plastic tubes containing Mecplant® substrate overlayered with vermiculite. Minicuttings were maintained in greenhouse for 120 days with temperature between 15 and 25ºC and 90% relative humidity. The parameters evaluated were: percentage of rooted, surviving and dead minicuttings, length of the three larger roots, number of roots and minicutting dry weight. Seedling age influenced the rooting percentage, and the highest value (85%) was obtained with 60-day-old seedlings. The winter was the most favorable season for the collection of minicuttings.