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Sustainable wood production is one of the current challenges due to the increasing demand for wood worldwide. Despite, forest planting has proved to be a good solution; the high wood productivity can be achieved only under favorable bioclimatic conditions, which makes this study of great value for government policies. This study aimed to assess the impact of climate on the distribution of Apuleia leiocarpa in Rio de Janeiro and Minas Gerais, Brazil. The Species Distribution Models (SDMs) were performed using the MaxEnt model-based on-field survey of A. leiocarpa (n = 54). Pedological and bioclimatic data were used to identify suitable areas and climate change effects on the distribution of this species. Ours results have shown that the MaxEnt presented a good performance in modelling the distribution of the A. leiocarpa. The temperature was the main controlling variable of the distribution of this species. The pedological models overestimated of the suitable area. Despite that, the results provide useful information to be considered in the future in order to refine the selection of variables for a better characterization of the ecological niche. Regarding the projection of the future A. leiocarpa distribution, there was found an alarming scenario, which it must be taken into the consideration for the local authorities in order to establish a successful species-replanting program.

The objective of this work was to evaluate the vegetative propagation of Hymenaea courbaril (jatobá) and Apuleia leiocarpa (garapa) using the mini-cutting technique with the use of indolebutyric acid (IBA) growth regulator in different types of mini-cuttings. Two experiments were set up: the first involving the two species and three mini-cutting techniques (basal, intermediate and apical) in the presence and absence of IBA (4000 mg kg-1). In the second experiment, only the garapa species was evaluated by testing the same three mini-cutting techniques at four IBA concentrations: 0, 1000, 2000 and 4000 mg kg-1. The mini-cuttings were obtained from 6-month-old seedlings produced from seeds in a nursery. A randomized block design was used in a 3 x 2 x 3 factorial scheme (three mini-cutting techniques, two IBA concentration levels and three evaluation dates) in the first experiment, and a 3 x 4 x 3 factorial scheme (three mini-cutting techniques, four IBA concentrations and three evaluation dates) in the second experiment. At 90 days, jatobá had an average survival of 54%, with less than 5% of total rooting, without significant influence of the mini-cutting technique or IBA use. Garapa presented higher survival for the basal mini-cuttings in both experiments, which were the only ones that took root. IBA did not influence survival or rooting percentage of garapa mini-cuttings, but negatively influenced the root number, length and dry mass. We concluded that the basal mini-cutting is a viable technique for vegetative propagation of garapa, presenting 40% of rooting, but the propagation by mini-cutting for jatobá was not successful under the conditions of this study. RESUMO O trabalho teve como objetivo avaliar a propagação vegetativa de Hymenaea courbaril (jatobá) e Apuleia leiocarpa (garapa) por meio da técnica de miniestaquia com o uso do regulador de crescimento, ácido indolbutírico (AIB), em diferentes tipos de miniestacas. Foram montados dois experimentos, o primeiro envolvendo as duas espécies, três tipos de miniestacas (basais, intermediárias e apicais), na presença e ausência de AIB (4000 mg kg-1). No segundo experimento, avaliou-se apenas a espécie garapa testando-se os mesmos três tipos de miniestacas em quatro concentrações de AIB: 0, 1000, 2000 e 4000 mg kg-1. As miniestacas foram obtidas a partir de mudas de 6 meses de idade, produzidas em viveiro a partir de sementes. Utilizou-se delineamento em blocos casualizados no esquema fatorial 3 x 2 x 3 (três tipos de miniestacas, dois níveis de AIB e três datas de avaliação) no primeiro experimento, e 3 x 4 x 3 (três tipos de miniestacas, quatro concentrações de AIB e três datas de avaliação) no segundo experimento. Aos 90 dias, o jatobá apresentou sobrevivência média de 54%, com menos de 5% de enraizamento total, sem influência significativa do tipo de miniestaca ou do uso do AIB. Em ambos os experimentos a garapa apresentou maior sobrevivência para as miniestacas basais, que foram as únicas que enraizaram. O AIB não influenciou a sobrevivência e o percentual de enraizamento de miniestacas da garapa, porém influenciou de forma negativa o número, comprimento e massa seca de raiz. Conclui-se para garapa que a miniestaquia, a partir das miniestacas basais se mostrou uma técnica viável, com 40% de enraizamento, porém para jatobá, nas condições do estudo, a propagação por miniestaquia não teve sucesso.

Forest association with arbuscular mycorrhizal fungi (AMF) can improve the uptake of nutrients and hence the growth of host plants and it exerts a crucial role in tropical nutrient-poor soils. Our work aimed to verify if there is natural mycorrhizal colonization in Plathymenia reticulata and Dalbergia nigra monospecific plantations. Soil sampling was collected in the vicinity of the trees and fine roots were selected. The fine roots were washed, clarified and then stained. The spore isolation and identification were assessed by the wet sieving and sucrose density centrifugation. Both P. reticulata and D. nigra roots have fungal structures (vesicles and hyphae). The species Glomus macrocarpum and Ambispora leptoticha were identified in the soil under P. reticulata and Glomus macrocarpum, Glomus agregatum, and Claroideoglomus etunicatum in the soil under D. nigra. Both species can naturally be associated with AMF and we can suggest that different fungi are colonizing the roots of each species.

Large-scale ecological restoration programs across the world involve a voluminous demand for native seeds of diverse native plant species. In this article, we explore how institutional systems have operated and impacted native seed supply in Brazil. Native seed supply for restoration is essentially a community-based activity which faces broad barriers to operating within regulations because of requirements for excessive and costly technical documentation, scarcity of seed laboratories, and lack of instructions for native seed quality testing. Although decentralized seed networks have stimulated arrangements for local organizations to promote seed supply, policies constrain the development of local capacities and the ongoing sustainability of these organizations. These conditions have resulted in a vast network of informal collectors and producers who are largely “invisible” and unknown to the regulatory authorities. Policies have decentralized responsibilities from the state without devolving decision-making power to the multiple stakeholders engaged in policy elaboration. The policies maintain the centralized regulation of native seed supply. After examining Brazilian seed networks’ experiences and conducting discussions with stakeholders and experts, we suggest adapting the current regulations to more local level contexts, encompassing the following strategies: (1) ensuring native seed origin and identity; (2) relaxation of the laboratory accreditation process for native seed quality assurance; (3) fostering seed markets for restoration; (4) research to provide technological innovation; (5) supporting local, diverse, and small seed-based businesses.

http://dx.doi.org/10.5902/1980509820592Seed size and dormancy level were studied in 20 trees from two populations of Schizolobium parahybatoevaluate how these characteristics occurbetween and within populations, and whether seed germinationwas affected by its morphometry. These two populations are located in the coastal (Paraty) or mountain(Miguel Pereira) regions in the state of Rio de Janeiro, Brazil. The seed morphometrictraits (length,width, thickness and weight) were measured. Germination with or without seedcoatdormancy treatment(mechanical scarification) wasassessedbya randomized emergence test in nursey. All morphometric traitsdiffered significantly among individuals and between populations. The trees from the mountain regionshowed a larger seed size and a lower dormancy level than that of trees from the coastal region. Seed sizehad no effect on seed germination or seedling development. Climate influence on the determination of germination behavior is discussed based on the results.

Estudos fenologicos podem servir de subsidio para acoes de colheita de sementes e recuperacao de areas degradadas, contribuindo para a conservacao das especies florestais. Este trabalho teve como objetivo conhecer a epoca de floracao e frutificacao de 21 especies arboreas nativas em area fragmentada de Mata Atlântica em Itaborai, RJ. Foram acompanhadas mensalmente 91 matrizes, no periodo de janeiro a dezembro de 2011. A maior parte das especies floresceu no final da estacao seca e inicio da chuvosa, tendo sido observada correlacao moderada e negativa entre floracao e fotoperiodo. Observaram-se dois picos de frutificacao: de marco a abril para as especies zoocoricas, e de setembro a outubro para especies nao zoocoricas, com correlacao positiva entre precipitacao e frutificacao de especies zoocoricas. Foi alta a incidencia de patogenos nos frutos, comprometendo a producao de sementes de Machaerium hirtum , Melanoxylon brauna , Machaerium brasiliense e Psidium guineense . Outras especies apresentaram baixa producao de frutos, como Andira sp., Swartzia oblata , Guarea guidonea e Enterolobium glaziovii . A sincronia de floracao e frutificacao entre as matrizes foi baixa para a maioria das especies. A falta de trabalhos de fenologia para a maioria das especies estudadas (52%) reforca a necessidade de pesquisa para a regiao de estudo.