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Abstract Half of the territory in Rio de Janeiro (RJ) state is composed of degraded areas. This work evaluated the profile, distribution, and production capacity of plant nurseries in RJ which produce forest seedlings, as well as their species’ richness. The potential to meet the increased demand arising from environmental commitments in different hydrographic regions was also analyzed. We identified 81 active forest seedling nurseries and 73 of them participated in our interview, by adopting a regional survey. Nearly one-third of the nurseries closed down in this region in the last decade. A high richness of species in the nurseries (977 species, 99 native species/nursery) was found, representing 22% of the regional flora. Most of this species’ richness is exclusively produced by small nurseries. The current production of the nurseries is capable of supplying less than 1% of the potential demand for seedlings for restoring priority watershed areas in the state.

ABSTRACT The present study aimed to evaluate the effect of inoculation with nitrogen-fixing bacteria (NFB) and arbuscular mycorrhizal fungi (AMF) on the development of Tachigali vulgaris seedlings under nursery conditions. The seedlings were produced in 1 kg bags on a substrate of sand and vermiculite (1:1), following a completely randomized experimental design in a 3 (NFB) x 2 (with and without AMF) factorial scheme with 3 additional control treatments consisting of: seedlings inoculated only with AMF (mycorrhizal control), non-inoculated seedlings fertilized with N (nitrogenized control) and without N (absolute control). The following variables were evaluated: height, stem diameter (SD), shoot dry mass (SDM), root dry mass (RDM) and nodule dry mass (NDM), P accumulation in the shoot, and root mycorrhizal colonization (RMC). Efficiency and effectiveness were calculated to evaluate the plant response to double inoculation. The treatments showed a significant effect for all variables, except for mycorrhizal colonization, nodule number, and dry mass, with the nitrogen treatment having the highest growth values. Plants submitted to double inoculation showed a higher accumulation of dry matter, height and SD, reaching a 124% higher RDM regarding the absolute control, 90% more SDM, and 207% more NDM regarding the seedlings inoculated only with rhizobia. The positive effect of double inoculation occurred regardless of the strain used. The results indicate that the joint inoculation of NFB and AMF was beneficial for the species, promoting its growth.

Seed size and dormancy level were studied in 20 trees from two populations of Schizolobium parahybato evaluate how these characteristics occurbetween and within populations, and whether seed germination was 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 traits differed significantly among individuals and between populations. The trees from the mountain region showed a larger seed size and a lower dormancy level than that of trees from the coastal region. Seed size had no effect on seed germination or seedling development. Climate influence on the determination of germination behavior is discussed based on the results.

O objetivo deste trabalho é avaliar a resposta de mudas de Mimosa bimucronata (DC) O. Kuntze à inoculação com estirpes de rizóbio previamente selecionados, utilizar diferentes substratos em condições de viveiro. Utilizou-se o delineamento experimental em blocos ao acaso com parcelas subdivididas, testando-se três substratos (organomineral puro contendo barro, areia e esterco na proporção 1: 1: 1 v: v: v, organomineral misturado com 30% de palha e areia com vermiculita na proporção 1: 1 v: v) e quatro fontes de N (inoculação com as estirpes BR 3461 e BR 3470, tratamento controle com nitrogênio e controle sem adubação), totalizando 12 tratamentos. Foramavaliados altura e diâmetro do colo após 90 dias e massas da parte aérea, das raízes e dos nódulos secos após 120 dias em viveiro. Os substratos organominerais permitiram o melhor desenvolvimento das mudas. Entretanto, somente o substrato organomineral com palha e a areia com vermiculita permitiram resposta da planta à inoculação com a estirpe BR 3470. O desempenho das mudas inoculadas não superou o das mudas adubadas com N. A dose de N aplicada estimulou a nodulação ao invés de inibi-la

Estudos fenológicos podem servir de subsídio para ações de colheita de sementes e recuperação de áreas degradadas, contribuindo para a conservação das espécies florestais. Este trabalho teve como objetivo conhecer a época de floração e frutificação de 21 espécies arbóreas nativas em área fragmentada de Mata Atlântica em Itaboraí, RJ. Foram acompanhadas mensalmente 91 matrizes, no período de janeiro a dezembro de 2011. A maior parte das espécies floresceu no final da estação seca e início da chuvosa, tendo sido observada correlação moderada e negativa entre floração e fotoperíodo. Observaram-se dois picos de frutificação: de março a abril para as espécies zoocóricas, e de setembro a outubro para espécies não zoocóricas, com correlação positiva entre precipitação e frutificação de espécies zoocóricas. Foi alta a incidência de patógenos nos frutos, comprometendo a produção de sementes de Machaerium hirtum, Melanoxylon brauna, Machaerium brasiliense e Psidium guineense. Outras espécies apresentaram baixa produção de frutos, como Andira sp., Swartzia oblata, Guarea guidonea e Enterolobium glaziovii. A sincronia de floração e frutificação entre as matrizes foi baixa para a maioria das espécies. A falta de trabalhos de fenologia para a maioria das espécies estudadas (52%) reforça a necessidade de pesquisa para a região de estudo.

RESUMO O trabalho teve como objetivo avaliar a eficiência de métodos de quebra de dormência em sementes de Albizia pedicellaris em laboratório. Foram aplicados 10 tratamentos pré-germinativos: escarificação química com imersão em ácido sulfúrico por 5, 10, 15 e 30 minutos, escarificação física, seguida ou não de embebição em água por 6, 12 e 24 horas, choque térmico e testemunha. Foi utilizado o delineamento inteiramente casualizado com 4 repetições, com 25 sementes por unidade experimental. Os seguintes parâmetros foram avaliados: percentual de germinação, índice de velocidade de germinação, número de plântulas normais, número de plântulas anormais, mortalidade. Com base nos resultados indicam-se como tratamentos para quebra de dormência da A. pedicellaris a escarificação mecânica seguida ou não de embebição por 6 ou 12 horas ou a imersão em ácido sulfúrico por 30 minutos.

ABSTRACT 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.