ABSTRACT
Desert teak (Tecomella undulata (Sm.) Seem) a multipurpose ornamental tree native to the arid and semi-arid tropics has entered the endangered plant category mainly as a result of the species' ineffective seed reproduction system. The tree usually reproduces through a few root suckers in old stands. Conventional methods of plants multiplication could not offer a viable practice for its mass multiplication. Low adventitious rooting of the cuttings has been the principal cause of failure in its vegetative propagation. Hence, the present research was planned and conducted to evaluate the feasibility of somatic embryogenesis in this species, the pathway that bypasses the need for rooting stage by developing bipolar embryos. Ovary explant was cultured in modified Murashigue & Skoog (MS) medium supplemented with different auxins and cytokinins. The results showed ?-naphthalene acetic acid (NAA) was superior in inducing embryogenic callus. NAA ranging 5.4-21.5 ?M could induce the highest embryogenic calli which exhibited developing pro-embryogenic masses (PEM) and globular somatic embryos. The calli which were induced by the use of 2,4-dichlorophenoxyacetic acid (2,4-D) were poor in quality and showed no morphogenesis potency. Individual application of Thidiazuron (TDZ) and N6-benzyladenine (BA) induced good callogenesis at low concentrations but the calli were non-embryogenic with both. The proliferation of embryogenic calli was the best in a hormone-free medium. However, the media containing 40.5 and 54 ?M NAA alone could induce somatic embryos along with callus proliferation. Low BA-contained medium (0.9-4.44 ?M) led to recurrent somatic embryogenesis. Neither BA and GA3, nor the elevating sucrose concentration could cause further development and maturation of the somatic embryos induced during previous stages (callogenesis and callus proliferation). More research is required to optimize the maturation stage. The findings of the present study can be useful for future studies in the micropropagation of this recalcitrant specieslationships in Indian mustard under heat stress and the differential remobilization efficiencies in the advanced breeding lines.
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Aim: The present study aimed to estimate the total carbon sequestration potential of a 20-years-old teak (Tectona grandis) plantation forest spread over an area of 23 ha (in Odisha under Eastern Ghats stretch) through analysis of above ground and below ground biomass carbon of trees and soil organic carbon (SOC) stock.Methodology: The sampling was carried out during May to July 2017. Random non-destructive quadrate method was used for vegetation analysis. Based on the girth, height, basal area and bio volume of trees, the above ground carbon (AGC), below ground carbon (BGC) and total carbon storage in biomass (CSB) of teak plantation forest was calculated. Similarly, soil samples were taken by a soil core sampler at different depths and based on their organic carbon, bulk density, stone and gravel contents, soil organic carbon (SOC) stocks of soil was calculated. Results: The total SOC stock and CSB of the entire teak plantation forest was 489.21 t and 6670 t, respectively, across an area of 23 ha. Taking two carbon pools into account, the total carbon sequestration (TCS) of teak plantation forest patch was 7159.21 t, which arrived to be 311.27 t ha-1 with AGC of 230.16 t ha-1 and BGC of 59.84 t ha-1 and TOC stock of 21.27 t ha-1. The highest contribution in terms of carbon storage was established by above ground carbon (74%) followed by below ground carbon (19%) and SOC (7%). Interpretation: The current study reflects that teak plantation forest has rich potential of carbon sequestration not only in tree biomass but also in the SOC form and this plantation can act as a potent reservoir of carbon in the Eastern Ghats of India
ABSTRACT
ABSTRACT: Production of Tectona grandis (teak) in integrated systems with livestock or agriculture demonstrates high potential of financial return. However, studies on the development of teak are still scarce, especially in the northern region state of Mato Grosso. In this study we sought to evaluate dendometric variables of a clonal population of teak in a forest-livestock integration system (LFIS), during a period of 53 months in the city of Alta Floresta, Mato Grosso, Brazil. For this purpose, three installments were samples, a total of 360 individuals, and for each the diameter was measured at 1.3 meters from the base so as to calculate the total volume, the current annual increment (CAI) and mean annual increment (MAI), and five adjusted regression models. The Hoerl model provided the highest adjusted coefficient of determination (R2aj), lowest standard error of estimate (Syx), coefficient of variation (CV %), and from this the growth curves were developed. Clonal stands of teakin the forest-livestock system presented increases in DBH, height and volume were superior in relation to other scientific studies with teak, indicating their viability in integrated systems with pastures in the region.
RESUMO: A produção de madeira de Tectona grandis (teca) em sistemas integrados com pecuária ou agricultura demonstra alta perspectiva de retorno financeiro. Entretanto, estudos sobre o desenvolvimento da teca ainda são escassos, principalmente na região norte de Mato Grosso. O objetivo do trabalho foi avaliar o crescimento das variáveis dendrométricos de um povoamento clonal de teca, em um sistema silvipastoril (iPF), ao longo de 53 meses, no município de Alta Floresta-MT, Brasil. Para isso, foram amostradas três parcelas, totalizando 360 indivíduos, sendo que em cada indivíduo foi mensurado o diâmetro a 1,3 m do solo e altura total. Em seguida realizou-se o cálculo do volume. Para descrever o crescimento da variável diâmetro, altura total e volume foi realizado o ajuste através de cinco modelos matemáticos que expressam o crescimento ao longo do tempo. Posteriormente, foram calculados o incremento corrente anual (ICA) e incremento médio anual (IMA). O modelo de Hoerl apresentou melhores resultados de R²aj, obteve menores valores para o erro padrão de estimativa (Syx) e para o CV%, com isso, foi selecionado para a elaboração das curvas de crescimento. O povoamento clonal de teca no iPF apresentou incremento em DAP, Altura e volume foram superiores em relação a outros estudos científicos com teca, indicando sua viabilidade em sistemas integrados com pastagens na região.
ABSTRACT
The influence of different factors on shoot proliferation and the occurrence of hyperhydricity in teak (Tectona grandis L.) have been studied. Four concentrations of BA (2.22, 4.44, 6.66 and 8.88 µM) and a control treatment with 0 BA were examined. Aiming at reducing the costs during commercial propagation by using gelrite in stead of agar, the use of both gelling agent in the proliferation and hyperhydricity was tested. In order to evaluate if hyperhydricity can be reduced by increasing the gelrite concentration in the culture medium, three concentrations (2.0, 2.5 and 3.0 g L-1) were tested in combination with 4.44 µM BA. The proliferation and occurrence of hyperhydricity during 21 successive subcultures were evaluated. The highest proliferation was achieved in the treatments with 6.66 or 8.88 µM BA. They yielded 5.22 and 5.56 shoots/explant, respectively. But also, the highest percent of hyperhydric shoots was achieved in this treatment. Gelrite resulted in a higher proliferation, but also an almost two times higher hyperhydricity as compared to agar-solidified media. Satisfactory reduction in hyperhydricity (18%) was achieved with 3.0 g L-1 gelrite. However, the successive subcultures onto proliferation in this treatment favored hyperhydricity compromising shoot quality and it´s competence to proliferate. in vitro teak plants were ex vitro rooted and then transferred to greenhouse conditions for acclimatization; ten weeks after transfer they were ready for field plantation.
Se estudió la influencia de diferentes factores en la proliferación y la ocurrencia de la hiperhidricidad in teca (Tectona grandis L.). Se probaron cuatro concentraciones de BA (2,22; 4,44; 6,66 and 8,88 µM) y un control sin BA. Con el objetivo de reducir los costos durante la propagación comercial se experimentó sustituir el agar por el gelrite, para lo cual se estudió en efecto de ambos gelificantes en la proliferación y la hiperhidricidad de los brotes. Se estudiaron, tres concentraciones de gelrite (2,0; 2,5 and 3,0 g L-1) combinadas con 4,44 µM BA, con el objetivo de evaluar si la hiperhidricidad podía ser reducida incrementando la concentración de gelrite. Se evaluó la proliferación de brotes y la ocurrencia de la hiperhidricidad durante 21 subcultivos. Se logró una alta proliferación de brotes en los tratamientos con 6,66 y 8,88 µM BA (5,22 y 5,56 brotes), pero el porcentaje de brotes hiperhídricos también se incrementó. El gelrite resultó en una alta proliferación de brotes, pero con mayor incidencia de la hiperhidricidad que el medio gelificado con agar. Se obtuvo una reducción satisfactoria de la hiperhidricidad (18%), cuando la concentración de gelrite se incrementó hasta 3,0 g L-1. No obstante, la multiplicación de los brotes en este tratamiento más allá del 11no subcultivo favoreció la hiperhidricidad, lo que afectó la calidad de los brotes y su competencia para la proliferación. Las plantas fueron enraizadas ex vitro, transferidas a condiciones de invernadero para su aclimatización y diez semanas después de la transferencia estaban listas para la plantación en campo.
Subject(s)
Forestry , Theca CellsABSTRACT
A ferrugem da teca, causada pelo fungo Olivea tectonae, foi constatada no estado do Mato Grosso em 2009, no município de Sinop e nos anos seguintes foi observada em outras regiões do estado. A doença causa manchas necróticas nas folhas da planta, que correspondem aos urediniósporos localizados abaixo da epiderme das folhas e, quando em grande intensidade, levam a desfolha precoce da planta. As plantas desfolhadas ficam debilitadas, o que afeta a produção de madeira. Os objetivos deste trabalho foram: (i) avaliar a influência da concentração e do fotoperíodo na germinação de urediniósporos de O. tectonae; (ii) avaliar a influência da temperatura de armazenamento dos urediniósporos, coletados de folhas caídas e de folhas ainda nas plantas, na germinação destes esporos. Os resultados obtidos mostraram que os maiores níveis de germinação foram na concentração de 6,25 x 104 esporos mL-1 exposto à luz constante por 24 horas (92,75%). Porém quando submetidos ao escuro absoluto, houve germinação de 91,31%, o que significa que esporos de O. tectonae podem germinar na presença e na ausência de luz. Verificou-se que a percentagem de germinação foi maior nos esporos coletados de folhas ainda na planta e armazenados a temperatura de -2°C.
The teak rust, caused by the fungi Olivea tectonae, was found for the first time in Mato Grosso in 2009, in Sinop city and in the next years it was observed in another regions of the state. The pathology cause necrotics spots in plant leaves, that correspond to the urediniospores located below the leaves epidermis and, when they occurs in high intensity, lead to premature defoliation of the plant. The defoliated plants get weakened, what affects the wood production. The objectives of this work were: (i) to evaluate the influence of concentration and photoperiod in the germination of O. tectonae; (ii) to evaluate the influence of the storage temperature of urediniospores, collected from fallen leaves and leaves still on the plants, in the spores germination. The results showed that the higher levels of germination were in the concentration of 6,25 x 104 spores mL-1 exposed to constant light for 24 hours (92,75%). However, when they were submitted to total dark, there was also germination of 91,31%, what means that Olivea tectonae's spores can germinate in both the presence and absence of light. The germination percentual was higher in spores collected from leaves still in the plant and stored at a temperature of -2°C.
Subject(s)
Trees , Photoperiod , Lamiaceae , FungiABSTRACT
O objetivo da pesquisa foi avaliar a resistência natural da madeira de teca (Tectona grandis) a fungos e térmitas xilófagos em condições de laboratório. As árvores empregadas possuíam 15 anos de idade, provenientes de um plantio da Empresa Celulose Nipo Brasileira - CENIBRA S.A., localizada no município de Belo Oriente, Estado de Minas Gerais. Para a determinação da resistência natural da madeira a agentes xilófagos, foram realizados ensaios de apodrecimento acelerado em laboratório com os fungos Postia placenta, Neolentinus lepideus, Polyporus fumosus, e de preferência alimentar com cupins subterrâneos Nasutitermes sp. Corpos de prova foram retirados em quatro posições no sentido medula casca: cerne interno (próximo da medula), cerne intermediário, cerne externo (próximo ao alburno) e no alburno, na altura de 1,30m do nível do solo e submetidos à ação dos fungos por 13 semanas e cupins por 45 dias. Constatou-se que o cerne da madeira de teca proveniente do Vale do Rio Doce, Minas Gerais, foi altamente resistente, tendo o cerne interno sido menos resistente que as demais porções do cerne à ação dos agentes xilófagos, enquanto a madeira de alburno foi classificada como de resistência moderada (Polyporus fumosus) ou resistente (Postia placenta e Neolentinus lepideus).
This research aimed to evaluate the natural resistance of teak wood (Tectona grandis) to xylophagous fungi and termites in laboratory conditions. It was used trees with fifteen years old, from a plantation of the Forest Enterprise Celulose Nipo Brasileira - CENIBRA S.A., located in Belo Oriente, Minas Gerais State, Brazil. To determine the natural resistance of teak wood in laboratory were employed the Postia placenta, Neolentinus lepideus, Polyporus fumosus and Fomes connatus fungi and to termites resistance was employed the feeding preference assay with subterranean termites Nasutitermes sp. Samples were taken from four positions in the stem (heartwood near the pith, heartwood intermediate, outer heartwood and sapwood) at 1,30m to soil level and submitted to the action of fungi for thirteen weeks and termites for 45 days. It was found that the heartwood of teakwood from the Vale do Rio Doce, Minas Gerais State, Brazil was highly resistant. The internal heartwood was less resistant than the other portions of the heartwood to action of wood decay agents, while the sapwood was classified as moderately resistant (Polyporus fumosus) or resistant (Postia placenta and Neolentinus lepideus).
ABSTRACT
O trabalho teve como objetivo determinar a capacidade produtiva local da teca em Monte Dourado, Estado do Pará, Brasil, por meio da análise de curvas de índice de sítio. Os dados foram obtidos pela análise de tronco de dez árvores dominantes de um povoamento com 26 anos de idade. Foram ajustados dez modelos de regressão e o critério de seleção obedeceu ao menor erro padrão da estimativa, ao maior coeficiente de determinação ajustado, à significância do teste F e dos coeficientes de regressão e à análise gráfica dos resíduos. As curvas de índice de sítio foram confeccionadas pelo método da curva-guia. O modelo de Spillman apresenta o melhor ajuste, por meio do qual foram geradas três curvas de índice de sítio de 16m a 24m na idade-índice de 26 anos. A região de Monte Dourado, PA, apresenta potencial produtivo para o desenvolvimento da teca.
The study aims to determine the local productive capacity of teak in Monte Dourado, Pará State, Brazil, with the analysis of site index curves. The data were obtained by stem analysis of ten dominant trees in a stand with 26 years of age. Were adjusted ten regression models and the criterion for selection followed the lowest standard error of estimate, the highest adjusted coefficient of determination, the significance of F test and of regression coefficients and graphical analysis of the residuals. The site index curves were built by the guide-curve method. The Spillman model present the best fit, by which were generated three curves of site index from 16m to 24m, at 26 years of index-age. The region of Monte Dourado - PA showed a productive potential for the development of teak.
ABSTRACT
Nas áreas de produção de sementes de Tectona grandis em Cáceres, MT, ventos fortes podem causar queda precoce de frutos. Diásporos de três lotes de teca, um obtido após a queda natural e os outros dois após queda precoce, foram inicialmente qualificados quanto ao teor de água, massa de mil diásporos, número de diásporos por quilograma, emergência em canteiro e respectivo tempo médio. Essas duas últimas variáveis foram novamente determinadas em intervalos de 50 dias até 331 dias após a colheita com o uso de 200 diásporos divididos em quatro repetições. Para os diásporos de queda natural, a emergência de plântulas e o tempo médio não diferiram nos períodos de análise com média geral de 60,6% e 10,8 dias. Os diásporos dos lotes de colheita precoce apresentaram a emergência inicial de 23,5 e 17,5% e os tempos médios de 19,4 e 22,6 dias, respectivamente. Até 115 dias após a colheita, a emergência aumentou (55,5 e 59,5%) e o tempo médio diminuiu (15,0 e 14,1 dias) e a partir daí ocorreu o inverso. Os diásporos de colheita precoce derrubados pelo vento apresentam maturação e o maior potencial fisiológico aos 115 dias após a colheita. No período de 64 a 269 dias após a colheita, esses diásporos atingem o padrão mínimo estabelecido para a teca e o período entre 115 a 165 dias é o mais adequado para sua utilização.
In the seed production areas of Tectona grandis in Cáceres, state of Mato Grosso, Brazil, strong winds cause the precocious fall of fruits. Diasporas of three lots of teak, one of then crop after the natural fall, and the others two after the precocious fall were characterized initially by the content of water, thousand diasporas mass, number of diasporas by kilogram, emergency in seedbeds and respective average time. With 200 diasporas divided in four replications and in periods of 50 days until 331 days after crop, the last two variables were determined again. To the diasporas of natural fall, the seedlings emergency and the average time were not different in periods of analyses with a general average of 60.6% and 10.8 days. The diasporas of the precocious crop lots presented respectively the initial emergency of 23.5 and 17.5% and the average time of 19.4 and 22.6 days. Until 115 days after crop, the emergency increased (55.5 and 59.5%) and the average time diminished (15.0 and 14.1 days) and on this point the inverse occurred. The diasporas of precocious crop fall by the wind present maturation and the greater physiological potential at 115 days after the crop. In the period at 64 to 269 days after crop, these diasporas reaches the established minimum standard for the teak and at 115 to 165 days is more adjusted period for its use.
Subject(s)
Crops, Agricultural , Lamiaceae , Emergencies , Seed Dispersal , Theca Cells , WindABSTRACT
O efeito da intensidade do primeiro desbaste seletivo, após um ano, foi avaliado em dois povoamentos de teca sob espaçamento 3,0 x 3,0 m, e em duas diferentes idades. No povoamento com quatro anos de idade, o desbaste foi de 20 por cento, 30 por cento e 40 por cento, em número de indivíduos, e no de cinco anos, de 30 por cento, 40 por cento e 50 por cento, e as respectivas testemunhas (0 por cento). Cada tratamento foi aplicado ao acaso, com oito repetições, contendo cada parcela 35 árvores, além da bordadura. Um ano após o desbaste aplicado no povoamento com quatro anos, as variáveis DAP, altura total (H) e as médias por árvore de área transversal (
) e de volume (
) não apresentaram diferenças significativas entre os tratamentos; o incremento corrente anual (ICA V) não foi afetado pelas intensidades. No povoamento desbastado aos cinco anos, o ICA V e H foram semelhantes em todos tratamentos. As intensidade de desbaste testadas não afetaram o crescimento em DAP, e , mas apresentaram diferenças significativas em relação à testemunha. O primeiro desbaste seletivo pode ser aplicado aos cinco anos de idade, em povoamentos de Tectona grandis com condições semelhantes, com qualquer das intensidades testadas.
The intensity of the first selective thinning was evaluated in two plantations, 3.0 x 3.0 m. In the four year old plantation, the thinning was 20 percent, 30 percent and 40 percent in density and in the five year old, it was 30 percent, 40 percent and 50 percent, and the respective controls (0 percent). Each treatment was applied in eight random blocks of 35 trees, beyond the border. One year after thinning at the age of four, the DBH, total height (H), and average by tree of basal area () and of volume () presented no differences among the treatments; the current annual increment (CAIV) was not affected by the intensities. In the plantation thinned at the age of five, the CAIV and H were similar in all treatments; the DBH, and were not affected by the tested intensities, but they were greater than the control. The first selective thinning may be applied at the age of five, in Tectona grandis plantations with similar conditions, at any tested intensity.