Reynaldo Campos Santana

Eficiência de utilização de nutrientes e sustentabilidade da produção em procedências de Eucalyptus grandis e Eucalyptus saligna em sítios florestais do estado de São Paulo

Nutrient use efficiency and growth of three provenances of Eucalyptus grandis and three of E. saligna were evaluated, at 78 months of age, on various sites located in the counties of Angatuba, Itapetininga, Paraibuna, Sao Miguel Arcanjo and Sao Jose dos Campos, in the state of Sao Paulo, Brazil. There was a variation in biomass production among sites, with the highest yield being obtained in Sao Miguel Arcanjo, followed by Paraibuna. The other counties constituted a third group. The genetic materials revealed variations in nutrient use efficiency from site to site. E. grandis showed greater N, P, and Mg nutrient use efficiency than E. saligna. There were no appreciable differences in efficiency between the two species for Ca and K. High nutrient use efficiency is not necessarily related to high productivity. Ca and K are the nutrients that could most limit productivity of the next rotation, when harvesting the stem. However, this limitation can be substantially reduced, especially for Ca, if only stemwood is harvested.

Alocação de nutrientes em plantios de eucalipto no Brasil

Forest management practices can alter nutrient exportation from the site. The purpose of this study was to estimate nutrient contents in the aboveground biomass of eucalyptus plantations in Brazil. The influence of key climatic variables on eucalypt productivity and nutrient content was evaluated, using the database from the Reserch Programa on Soil and Eucalyptus Nutrition of the Soil Science, Departament - Federal University of Vicosa, Minas Gerais State, Brazil. Climatic characteristics were an important component of the models. In regions with low water availability the nutrient accumulation in aboveground biomass as well as biomass production were lower. The highest proportion of all nutrients (68 % N, 69 % P, 67 % K, 63 % Ca, and 68 % Mg) was accumulated in the biomass within 4.5 years after planting for harvesting after approximately 6.5 years. After 4.5 years, the potential of fertilizer response was lower. Canopy and stem bark together accounted for 65 % N, 70 % P, 64 % K, 79 % Ca, and 79 % Mg in the aboveground biomass. Debarking in the field can therefore substantially reduce nutrient exportation and contribute to a more sustainable production in eucalyptus plantations.

Estimativa de biomassa de plantios de eucalipto no Brasil

The aim of this work was to model growth of eucalypt plantations in Brazil. It was intended to evaluate influence of key climatic variables on eucalypt productivity. The database employed was obtained from the Soil and Eucalypt Nutrition Program of the Soil Department of the Federal University of Vicosa. Climatic characteristics and age were a model important component. The region with the highest productivity produced three times more aboveground biomass than the poorest region. Regions with low water availability exhibited the lowest biomass production. Strong reduced in canopy proportion was observed within 3.5 years following planting. After that the canopy proportion reduced more slowly.

Micropropagação de sucupira-preta por meio de gemas axilares

O objetivo deste trabalho foi avaliar o uso de reguladores de crescimento, aditivos antioxidantes, tipo de explantes e intensidade de cobertura de mudas aclimatizadas, na micropropagacao de sucupira‑preta ( Bowdichia virgilioides ) por meio de gemas axilares. Os explantes foram cultivados para a multiplicacao em meio de cultura basico WPM, suplementado com concentracoes de benzilaminopurina (BAP). No alongamento, os tratamentos foram combinacoes de acido naftalenoacetico (ANA) e BAP adicionadas ao meio. Para o enraizamento, as brotacoes foram colocadas em meio com concentracoes de acido indolbutirico, ou em meio com combinacoes dos aditivos polivinilpirrolidona e carvao ativado, em diferentes concentracoes de ANA. As plantas foram transplantadas para copos de plastico, com substrato, e cobertas com saco de polietileno. Posteriormente, esses sacos foram retirados, ou perfurados, ou nao retirados, o que constituiu os tratamentos de pre‑aclimatizacao in vitro. A aclimatizacao ex vitro foi realizada apos o periodo de pre‑aclimatizacao in vitro. A sucupira‑preta apresentou melhor micropropagacao com emprego de: segmentos cotiledonares e 0,3 mg L -1 de BAP, na multiplicacao; 0,3 mg L -1 de ANA e 0,03 mg L -1 de BAP, no alongamento; e carvao ativado (2,0 mg L -1 ), no enraizamento e na pre‑aclimatizacao in vitro, com uso de cobertura de plastico transparente em torno da muda.

Padrões de miniestacas e sazonalidade na produção de mudas clonais de Eucalyptus grandis Hill X E. urophylla S. T. Black

The present study aimed to evaluate the influence of different patterns of mini-cuttigs on rooting and production of hybrid Eucalyptus grandis Hill x E. urophylla S. T. Black hybrid in summer and winter. Experiments with five clones and 12 different patterns of mini-cuttings were conducted in two seasons (summer and winter). The survival and rooting were evaluated ate the output greenhouse and output of the shade and in full sun, survival, height, diameter, the dry weight of shoot and root. The results indicated that the maintenance of leaves is important for rooting mini-cuttings of Eucalyptus grandis Hill x E. urophylla S. T. Black hybrids, and the basal leaves had higher values of rooting. Seedlings produced in summer, using cuttings of 10 cm in size, had higher growths methodology leaves no reduction procedure proved suitable for seedling production in both seasons.

Populações, matrizes e idade da planta na expressão de variáveis físicas em frutos do pequizeiro

Pequi is a very common tree in Central and Center-East Brazilian territory, known as Cerrado sensu strict, and its fruits are largely appreciated by people that live in these regions. This study was proposed due to the lack of information about environmental and genetic effects on physical attributes expression in pequi fruits. Information on this subject is relevant to favor decisions regarding to domestication and breeding processes of this species. Pequi fruits were collected from populations of Curvelo and Sao Goncalo do Rio Preto, State of Minas Gerais, being 15 mother trees per population. These mother trees were selected based on physical attributes that imply their age, being stem diameter at ground level (SD), the main one. Physical attributes were: fruit Total Weight (FTW); Outer Mesocarp Weight (OMW); Putamen Weight per fruit (PW); Putamen Number per fruit (PN) and Pulp Total Weight per fruit (PLTW). There was a mother tree effect for all attributes evaluated, whereas for populations, there was effect only for PN. Correlations among all variables were positive, being some of them significant. Also, correlations between SD and all other variables were positive and some, significant. Results allow the conclusion of high expected gains through vegetative propagation of mother tree selected by means physical fruit attributes: pulp weight can be selected based on putamen weight; the effect of plant age on fruit physical attributes is null or positive, so the selection can be carried out in youth plants.

Produção e acúmulo de nutrientes em povoamento de eucalipto em consequência da intensidade do desbaste e da fertilização

O objetivo deste trabalho foi estimar a producao de madeira e biomassa, bem como a quantidade de nutrientes acumulada, em povoamento de eucalipto submetido a intensidades de desbaste e a fertilizacao pos-desbaste. O experimento foi realizado em blocos ao acaso, em parcelas subdividas, com duas repeticoes dos tratamentos dentro de cada bloco. Nas parcelas, foram avaliadas quatro intensidades de desbaste (0, 20, 35 e 50%) e, nas subparcelas, as condicoes com e sem fertilizacao pos-desbaste. O desbaste foi realizado aos 89 meses e a aplicacao da fertilizacao aos 99 meses. Os dados foram coletados aos 125 meses. O desbaste influenciou o crescimento em diâmetro, area basal, volume de madeira e biomassa. A fertilizacao pos-desbaste nao afetou o acumulo de nutrientes pelo povoamento nem sua producao. O acumulo de nutrientes na parte aerea e no tronco foi inversamente proporcional a intensidade dos desbastes. O conteudo de Ca na serapilheira variou de acordo com os desbastes, e o de K, Ca, Mg e S de acordo com a fertilizacao. O desbaste tem maior influencia do que a fertilizacao na producao florestal pos-desbaste.

Estimação do volume de árvores de clones de eucalipto pelo método da similaridade de perfis

RESUMO ‐ Os objetivos deste trabalho foram desenvolver e propor um procedimento para quantificacao do volume de arvores em plantios clonais de eucalipto nao desbastados. Para quantificar o volume de arvores, foram utilizados dados de 2.036 arvores de clones comerciais de eucalipto pertencentes a empresa CAF Santa Barbara, onde foram ajustadas as equacoes de volume de cada estrato, sendo este determinado pela regiao e pelo clone, e as idades dos clones variaram de 4 a 5 anos. Para cada arvore foi ajustado um modelo de afilamento. Posteriormente, foram realizados abates de tres arvores de clones novos, que nao possuiam equacao de volume especifica, sendo uma arvore “pequena”, uma “media” e uma “grande” em termos de dap e altura total. Com as tres arvores cubadas, foi ajustado o modelo de afilamento, considerando-se as tres arvores. De posse das estimativas dos parâmetros, foi calculada uma medida de similaridade com os parâmetros das equacoes de afilamento ajustadas para as 2.036 arvores dos clones comerciais e o parâmetro da equacao do clone novo. A arvore do clone comercial que apresentou o menor valor de distância euclidiana, em comparacao com o clone novo, foi considerada a mais similar; portanto, a equacao de volume desse clone comercial foi usada para estimar o volume de arvores desse novo clone. Tal procedimento foi denominado metodo da similaridade de perfis. Esse metodo pode ser usado para estimar volume de arvores dos clones que nao tem equacoes especificas, gerando estimativas semelhantes ao comparar dados observados e estimados, tanto de arvores individuais quanto de todo um talhao.

REDUÇÃO FOLIAR EM MINIESTACAS E MICROESTACAS DE CLONES HÍBRIDOS DE Eucalyptus globulus

The objective of this study was to evaluate the effect of leaf reduction in the rooting of two types of mini-cuttings and micro-cuttings (apical and intermediate) of four hybrid clones of Eucalyptus globulus. Evaluations were performed on the percentage of survival, roots at the lower end of the tube, rooting, height, stem diameter, dry weight of shoot and root. At 90 days, it can be concluded that the apical cuttings with and without leaf reduction were higher than the intermediate cuttings, besides each clone behaved differently in relation to the rooting of mini-cuttungs and micro-cuttings. Vegetative propagation by apical cuttings without leaf reduction can be recommended for the production of seedlings of Eucalyptus urophylla x E. globulus and Eucalyptus grandis x E. globulus.

Germinação e Crescimento Inicial Entre Matrizes de Duas Espécies do Gênero Hymenaea

The Hymenaea genus belongs to the family Leguminosae, subfamily Caesalpinoideae with the common name jatoba. Approximately 25 species have been described in the genus Hymenaea and 13 of them are present in Brazil. Among them we can highlight the species Hymenaea martiana Hayne and Hymenaea courbaril Linneaus. In literature, there are several studies dealing mainly the dormancy breakage and the seedling production, mainly with Hymenaea coubaril Linneaus, but these reviews per matrices are incipient. This study aimed to evaluate and compare the germination and seedling growth between species and between matrices of the Hymenaea martiana Hayne and Hymenaea courbaril Linneaus. Two experiments were conducted: the first evaluated the germination and the second the seedlings growth. The two species studied showed different behavior between germination and the seedling growth, with Hymenaea courbaril Linneaus showing the greatest average for both variables. However, this did not show phenotypic variability between matrices.