Ana Catarina Monteiro Carvalho Mori da Cunha

Produtividade e sobrevivência de minicepas de Eucalyptus benthamii Maiden et Cambage em sistema de hidroponia e em tubete.

This work aimed to evaluate the productivity and survival of Eucalyptus benthamii ministumps from seminal origin, handled in hydroponics systems and in plastic tubes. The survival differences was not verified among the handling systems studied, while for the productivity of the ministumps the hydroponic systems presented best results, with average of 8,1 minicuttings per ministumps per collection in comparison with 4,1 for the plastic tubes system. These results allowed to conclude that the handling of the ministumps in tubes and in hydroponic systems is technically viable, being the latter a more promising alternative for production of vegetative propagules of the species.

MACRONUTRIENTES NA PRODUÇÃO DE MUDAS DE CANAFÍSTULA EM ARGISSOLO VERMELHO AMARELO DA REGIÃO DA ZONA DA MATA, MG

The objective of this work was to evaluate the effect of macronutrients doses upon the growth and quality indices of Peltophorum dubium seedlings and to determine the recommended doses for them to establish a suitable fertilization program. In the paper, carried out in a greenhouse, samples of ‘Red Yellow Ultisol’ were used, removed from the layer below, 20 cm deep, as a substratum. The experiment was designed in a Baconian Matrix, and three doses of the six macronutrients (nitrogen, phosphorus, potassium, calcium, magnesium and sulfur) and two additional treatments were evaluated, one with reference doses and the other one without the addition of nutrients. The entirely casual design was adopted, with four repetitions. The morphologic parameters and quality indices of seedlings were analyzed. Through the orthogonal contrasts, a significant response of all the variables studied was verified related to the macronutrient applied, except for the relation height/diameter (H/D) in the treatments with Ca, P and S. It was not verified response to Ca application for most characteristics evaluated, unless for the relation of the aerial part height per aerial part dry weight (H/MSPA) and aerial part dry weight per root dry weight (MSPA/MSR). The recommended doses were of 600 mg dm -3 of P, 150 mg dm -3 of K, 0,50 cmol c dm -3 of Mg and 50 mg dm -3 of S. Based on this work, further studies are suggested with N and Ca, for seedlings production of the studied species using from the layer below 20 cm deep of the ‘Red Yellow Ultisol’ as the substratum.

Resposta de mudas de Senna macranthera cultivadas em Argissolo Vermelho-Amarelo a macronutrientes

Senna macranthera has great natural occurrence, with potential use in the recovery of degraded areas. However, there is need for information on the nutrition of native forest species. In that sense, the objectives of this study were to evaluate the effect of doses of N, P, K, Ca, Mg and S on growth and quality indices of seedlings of Senna macranthera and to determine their recommended doses. This study was carried out in a greenhouse, using a Red Yellow Argisol, removed from the layer below 20 cm depth, as substratum. The experiment was designed in a Baconian Matrix, and three doses of the six macronutrients and two additional treatments were evaluated, one with reference doses (fertilizer used by default for native species) and the other one without the addition of nutrients. An entirely casualized design was adopted, with four repetitions. The morphologic parameters and quality indices of seedlings were analyzed. Through orthogonal contrasts, a significant response of all the variables studied was verified in relation to the macronutrients applied. The species was most demanding of P and K in comparison to the other macronutrients, and the recommended doses were of 600 mg dm -3 of P and 200 mg dm -3 of K. It is recommended that further studies with lower doses of the nutrients N, Ca, Mg and S be carried out, since, according to this study, the best doses for these nutrients were found for the original soil used as substrate and the lowest dose of the applied treatment.

Produção de mudas de canafístula cultivadas em latossolo vermelho amarelo álico em resposta a macronutrientes

Peltophorum dubium (canafistula) is a fast-growing, rustic species excellent for use in combined reforestation of degraded areas. The objective of this study was to evaluate the effect of doses of N, P, K, Ca, Mg and S on seedling growth and quality indices; and to determine the recommended dose of these elements for establishment of a suitable fertilization program. The study was conducted in a greenhouse using red-yellow alic latosol as substrate. The experiment was designed following a Baconian matrix, evaluating three doses of the six macronutrients and two additional treatments, one with reference doses and another with no addition of nutrients. A completely randomized design was adopted with four replicates. Analysis using orthogonal contrasts revealed a signifi cant response from all variables being studied to application of macronutrients, except the H/D ratio. The nutrients P and N had the most signifi cant effects, 540 mg/dm3 being the recommended dose of P, and 50 mg/dm3 being the recommended dose of N. No response was observed to application of K, Ca, Mg and S, for most traits being assessed, indicating that the species has a low requirement for these nutrients.

Estabelecimento in vitro de Peltophorum dubium ((Spreng.) Taub.) em função das concentrações do meio MS

Neste trabalho, objetivou-se verificar a influencia de diferentes concentracoes do meio MS no estabelecimento in vitro de segmentos apicais caulinares (80-100 mm) de canafistula isolados, a partir de plântulas germinadas em condicoes assepticas. As concentracoes de sais de 50, 75, 100, 125 e 150% do meio de cultivo MS, foram suplementadas com 30 g L-1 de sacarose, 100 mg L-1 de mio-inositol, 7 g L-1 de agar e o pH, ajustado para 5,7. O delineamento experimental foi o inteiramente casualizado, com 20 repeticoes, cada uma consistindo de um frasco contendo um explante. As culturas foram mantidas por 60 dias em sala de cultivo sob fotoperiodo de 16 horas, intensidade luminosa de 20 µmol m-2 s-1 e temperatura de 25±2oC. Nao houve efeito das diferentes concentracoes do meio MS para a maioria das variaveis, sendo observadas elevadas medias gerais de sobrevivencia (98%) e de estabelecimento (98%) in vitro. O maior numero de folhas (2,8) ocorreu na diluicao de 75%, com reducao a partir dessa diluicao. Nessa mesma concentracao, houve a maxima calogenese, que foi diminuindo ate nao ser observada sob 125% da composicao original; a 150% houve, novamente, presenca de calos. Nao ocorreu enraizamento de explantes durante o cultivo in vitro. Considerando-se o conjunto das variaveis avaliadas e, adicionalmente, que a presenca de calos nao e desejavel, recomenda-se o emprego da concentracao original de sais do meio de cultivo MS no estabelecimento in vitro de segmentos apicais caulinares de canafistula.

EVALUATION OF SUBSTRATES AND AMF SPORULATION IN THE PRODUCTION OF SEEDLINGS OF NATIVE FOREST SPECIES

The objective of this study was to evaluate organic substrates in the production of canafistula (Peltophorum dubium) (Spreng.) Taub, cutieira (Joannesiaprinceps Vell.), jatoba (Hymenaea courbaril L.) and rubber tree (Hevea brasiliensis M. Arg.) seedlings, native trees with potential use in forest restoration programs. The design was completely randomized with 10 substrate formulations with 4 repetitions of 3 plants for the four species. The evaluated substrates consisted of soil, bovine manure (BM), poultry manure (PM), chemical fertilizer (CF) and sand, in different proportions. The experiment was concluded at the end of 180 days for canafistula, cutieira and rubber and 210 days for jatoba. At the end of these periods, the root (RDM), shoot (SDM) and total (TDM) the dry matters of the seedlings were determined. Quantification of AMF spores and normalization between samples through SPORES/RDM correction were also performed. The Scott-Knott test at 5% probability was applied. Regarding biomass production, only canafistula had significant difference among the tested substrates. In relation to sporulation, the highest values were observed in cutieira and rubber tree in substrate containing PM. The substrates composed of 40 or 50% soil + 20% sand + 30% or 40 PM for canafistula; 50% soil + 20% sand + 30% PM for cutieira; and for jatoba and rubber tree 60% soil + 20% sand + 20% PM, enabled the best results in terms of biomass production in seedlings and AMF sporulation.

Efeito de macronutrientes sobre o crescimento e qualidade de mudas de canafístula cultivadas em Latossolo Vermelho-Amarelo distrófico

Peltophorum dubium (canafistula, angico-cangalha, angico-amarelo) e uma especie de rapido crescimento, rusticidade e otima para uso em reflorestamentos mistos de areas degradadas. Devido a carencia de informacoes sobre a nutricao dessa especie, o objetivo deste trabalho foi avaliar o efeito de doses de N, P, K, Ca, Mg e S sobre crescimento, producao de biomassa e indices de qualidade de mudas H/D, H/MSPA, MSPA/MSR e IQD, e determinar a dose recomendada destes elementos. No trabalho, realizado em casa de vegetacao, foi utilizado Latossolo Vermelho-Amarelo distrofico como substrato. Delimitou-se o experimento por meio de matriz baconiana, avaliando-se tres doses dos seis macronutrientes e dois tratamentos adicionais, um com doses de referencia e outro sem adicao de nutrientes. Adotou-se o delineamento inteiramente casualizado com quatro repeticoes. Verificou-se, atraves de analise dos contrastes ortogonais, uma resposta significativa de todas as variaveis estudadas com a aplicacao dos macronutrientes. Os nutrientes que mais surtiram efeitos significativos foram o P e o Mg, sendo recomendada dose de 600 mg/dm3 de P, 0,2 cmolc/dm3de Mg, e doses minimas de 50 mg/dm3de K e 0,8 cmolc/dm3 de Ca. Nao foi verificada resposta a aplicacao de N e S, para nenhuma das caracteristicas avaliadas, o que indica que a especie tem baixo requerimento por estes nutrientes.

Inoculação com esporos de Pisolithus microcarpus e adição de fosfato natural em mudas de Eucalyptus grandis

The objective of this study was to evaluate the use of spores of Pisolithus microcarpus and rock phosphate (RP) in low-cost inoculation programs of Eucalyptus grandis in nurseries. Although the treatments did not increase plant growth, there was significant difference in dry mass of the root system and partition of carbon in the plant. Inoculation promoted a significant increase in the mycorrhization rates, but the doses of RN used in this study did not affect the establishment of the association. Additional studies are being conducted to optimize the procedure and inoculated with spores.

Inoculation with spores of Pisolithus microcarpus and amendment with rock phosphate in seedlings of Eucalyptus grandis

No solo de ecossistemas florestais de importância economica e para o dia a dia do pequeno produtor, destaca-se a associacao ectomicorrizica (READ; PEREZ-MORENO, 2003). Trata-se de uma associacao simbiotica mutualistica entre as raizes das plantas e fungos especializados do solo que e caracterizada por suas estruturas tipicas: a rede de Hartig e o manto fungico (PETERSON; FARQUHAR, 1994; SMITH; READ, 2008). A rede de Hartig caracteriza-se pelo crescimento de hifas, nos intersticios das celulas das O objetivo deste trabalho foi avaliar a utilizacao dos esporos de Pisolithus microcarpus e de fosfato de natural (FN) em programas de inoculacao de baixo custo de Eucalyptus grandis em viveiros. Embora os tratamentos nao tenham provocado maior crescimento da parte aerea das mudas, verificou-se diferenca significativa na massa seca do sistema radicular e na particao de carbono na planta. A inoculacao promoveu aumento nas taxas de micorrizacao, embora as doses de FN utilizadas neste trabalho nao tenham afetado o estabelecimento da associacao. Estudos adicionais estao sendo conduzidos para otimizar o procedimento de inoculacao com esporos.