Brazilian forest ecosystems carry ubiquitous and rare species of arburcular mycorrhiza fungi (AMF). The method of spore morphology underestimates AMF diversity in forest ecosystems. The AMF are not specific to host-plant but to the environments where plants grow. Ubiquitous AMF species may be a source of AMF inocula for forests.

Este trabalho teve como objetivo caracterizar a composição florística e a estrutura da comunidade arbórea de áreas em processo de recuperação ambiental no município de Bocaiúva do Sul-PR. A produção e divulgação de dados e informações sobre a florística e fitossociologia da cobertura florestal em duas áreas com condições ambientais e intervenções distintas é uma contribuição relevante para compreender a dinâmica na estrutura arbórea em áreas de recuperação ambiental. Para isso, foram selecionadas duas áreas com distintos graus de degradação: Floresta Secundária Inicial (FSI), área na qual houve corte raso, isto é, retirada das camadas superficiais do solo e revegetação com Mimosa scabrella Benth; e Floresta Secundária Avançada (FSA), que representa um fragmento de Floresta Ombrófila Mista em que houve exploração seletiva de espécies de interesse comercial. A amostragem da vegetação foi realizada em 10 parcelas de 150 m² em cada área (0,15 ha), nas quais foram mensurados todos os indivíduos arbóreos, incluindo as árvores mortas com circunferência a altura do peito (CAP) igual ou superior a 15 cm. Na FSI, foram amostradas 40 espécies pertencentes a 24 famílias, enquanto na FSA foram amostradas 57 espécies pertencentes a 27 famílias botânicas. Os resultados apontaram que a estrutura da vegetação na FSA é distinta da FSI, com menor densidade de árvores, maior área basal e diversidade florística.

Eucalyptus benthamii is a tree species commonly planted in subtropical areas, including the Southern Brazil, due to its tolerance to low temperatures and frosts. The success of E. benthamii plantation depends on the seedlings vigor during transplantation. We hypothesized that improvement of chemical and biological properties of growth substrate would produce more vigorous E. benthamii seedlings. Thus, we applied increasing doses (0, 0.5, 1.0, 1.5 and 2.0 g per seedling) of the organic fertilizer Bacsol, which carries a consortium of potential plant growth promoting microorganisms, on the substrate, and measured the growth and development of E. benthamii seedlings. Two experiments were performed in 2011 and 2012. The first experiment included measurements in four growth stages to estimate the relative growth rates. The second one ended at the time that seedlings reached standard heights for transplantation (about ± 20 cm). Measurements on plant height, stem diameter, shoot dry weight and relative growth rates indicated that the application of Bacsol improved E. benthamii seedlings vigor and decreased the time needed in nursery, from 150 days to 90 days. The best responses occurred at doses from 1.3 g to 1.5 g per seedling. The data demonstrated that application of Bacsol in substrate is a promising technology to increase E. benthamii seedlings vigor.

Resumo A Floresta Nacional de Irati é a área protegida com a maior superfície de Floresta Ombrófila Mista (1.585,45 ha)

Black wattle (Acacia mearnsii De Wild.) is a tree legume native to southeast Australia, but present in all continents. Today it covers about 142,400 ha in Brazil, with plantations concentrated in the southern region of the country. Black wattle may form nodules and establish rhizobial symbiosis capable of fixing N 2 , but rhizobial inoculation is not done in commercial plantations. About 40 kg ha −1 of urea is applied during seedling transplantation. In this review, evidences by which rhizobial inoculation affects monoculture, mixed cultivation, and agroforestry black wattle production systems were searched in literature. Previous measurements in cultivated forests have indicated that biological nitrogen fixation in black wattle may provide up to 200 kg of N ha −1 year −1 to the soil. Therefore, rhizobia inoculation may bring several opportunities to improve black wattle production systems. Black wattle is not a very selective partner in the rhizobial symbiosis, but the genus Bradyrhizobium dominates the rhizobial diversity of black wattle nodules. Investigation on rhizobial diversity in soils where the crop is cultivated may represent an opportunity to find more effective rhizobia strains for inoculants. The successful history of biological nitrogen fixation in grain legumes must inspire the history of tree legumes. Microbiology applied to forestry must overcome challenges on the lack of trained professionals and the development of new application technologies.