GERMINAÇÃO E PROPAGAÇÃO IN VITRO DE MOGNO BRASILEIRO (Swietenia macrophylla King)

A intensificação da exploração seletiva de madeiras tem ocasionado grandes perdas na biodiversidade de espécies nativas de alto valor econômico, comprometendo, a sua sobrevivência. O potencial madeireiro do mogno brasileiro é mundialmente reconhecido e, por isso, é também motivo de grande preocupação da comunidade científico. Esta pesquisa objetiva avaliar o efeito de concentrações de reguladores de crescimento na germinação e multiplicação in vitro de mogno brasileiro e analisar aspectos físicos para determinar a eficiência na produção de mudas. Para isso, as sementes foram incubadas em meio de cultura MS no delineamento inteiramente casualisado em esquema fatorial 2 x 4 (duas intensidades de luz e quatro tempos de hipoclorito de sódio), com cinco repetições e quatro sementes por repetição. Aos trinta dias, os explantes isentos de contaminação foram transferidos para tubos de ensaio contendo meio MS e suplementados com diferentes concentrações de BAP e mantidos em sala de crescimento. Para multiplicação os brotos foram transferidos para meio MS e suplementados com diferentes concentrações de BAP e ANA. Obtiveram-se a maior porcentagem de brotações (83%) de explantes da porção intermediária de mogno e a utilização de concentrações superiores de ANA e BAP para formação de calos permitindo êxito na produção clonal. Palavras-chave: espécie nativa; plantas lenhosas; micropropagação. Germination and propagation in vitro of brazilian mahogany (Swietenia macrophylla King) ABSTRACT: The intensification of selective logging causes great losses biodiversity of native species of high economic value, compromising their survival. The wood industry potential of brazilian mahogany is recognized worldwide and, therefore, it is also a cause of great preoccupations of the scientific community. This research aims to evaluate the effect of concentrations of growth regulators on germination and in vitro multiplication of brazilian mahogany and analyze physical aspects to determining the efficiency in the production of seedlings. For this, the seeds were incubated in MS culture medium in a completely randomized design in a factorial scheme 2 x 4 (two light intensities and four sodium hypochlorite times) with five repetitions and four seeds per supplemented with different concentrations of BAP and kept in the repetition. At thirty days, explants free from contamination were transferred to test tubes containing MS medium and supplemented with different BAP concentrations and kept in the growth room. For multiplication the shoots were transferred to MS medium and supplemented with different concentrations of BAP and ANA. The highest number of percentage of shoots (83%) in the use of explants of the intermediate mahogany and the higher concentrations of ANA and BAP for callus formation enabling success in clonal production. Keywords: native species; woody plants; micropropagation.

Laelia anceps Lindl. (Orchidaceae) adaptation on phorophytes within an anthropized landscape, Amatlán de los Reyes, Veracruz, Mexico

Objective: To determine the best phorophyte species for the adaptation of the Laelia anceps Lindl orchid. (Orchidaceae) in an anthropized landscape. Design/methodology/approach: A completely randomized experimental design with four treatments (phorophytes) was used: Swietenia macrophylla King., Fraxinus sp., Persea schiedeana Nees. and Tecoma stans. (L.) Juss. ex Kunth), with five repetitions per phorophyte and with three L. anceps orchid plants in each phorophyte. The following variables were measured: day to emergence, root length and thickness, and survival at 28 weeks after tying them in phorophytes. Results: Root emergence of L. anceps occurred in less time in S. macrophylla and in Fraxinus sp. at 52 and 54 days respectively; the longest root length (19.11 cm) and number of roots (32.45) were observed in S. macrophylla. However, the root thickness was greater in Fraxinus sp. (0.28 cm). After 28 weeks of establishing the L. anceps plants; 100% survival was obtained in the phorophytes S. macrophylla and Fraxinus sp., 77% in P. schiedeana and 33% in T. stans. Study limitations/implications: The amount of light received by L. anceps in each phorophyte was not measured. Findings/Conclusions: The best phorophytes for the establishment of L. anceps were S. macrophylla and Fraxinus sp. observed, the best development and strength of the roots and 100% survival at 28 weeks.

Thermal Niche for Seed Germination and Species Distribution Modelling of Swietenia macrophylla King (Mahogany) under Climate Change Scenarios

Swietenia macrophylla is an economically important tree species propagated by seeds that lose their viability in a short time, making seed germination a key stage for the species recruitment. The objective of this study was to determine the cardinal temperatures and thermal time for seed germination of S. macrophylla; and its potential distribution under different climate change scenarios. Seeds were placed in germination chambers at constant temperatures from 5 to 45 °C and their thermal responses modelled using a thermal time approach. In addition, the potential biogeographic distribution was projected according to the Community Climate System Model version 4 (CCSM4). Germination rate reached its maximum at 37.3 ± 1.3 °C (To); seed germination decreased to near zero at 52.7 ± 2.2 °C (ceiling temperature, Tc) and at 12.8 ± 2.4 °C (base temperature, Tb). The suboptimal thermal time θ150 needed for 50% germination was ca. 190 °Cd, which in the current scenario is accumulated in 20 days. The CCSM4 model estimates an increase of the potential distribution of the species of 12.3 to 18.3% compared to the current scenario. The temperature had an important effect on the physiological processes of the seeds. With the increase in temperature, the thermal needs for germination are completed in less time, so the species will not be affected in its distribution. Although the distribution of the species may not be affected, it is crucial to generate sustainable management strategies to ensure its long-term conservation.

The role of the mahogany tree (Swietenia macrophylla King) on quantity and quality of water that fall below the canopy

Mahogany trees (Swietenia macrophylla) are often planted in urban forests area. This shady-crowned tree has a role in controlling the quantity and quality of rainwater that falls to the ground. Mahogany trees also affect the quality of rainwater through interception, fall, and stemflow. The purpose of this research was to determine the impact of the interception process, such as throughfall and stemflow, on changes in rainwater quality of the mahogany tree. The Data that needed to be measured were tree dimension, rainfall interception, and rainwater quality. Interception measurement was performed by calculating the number of throughfall and stemflow in one month-measurement. While the measurement of rainwater quality was measured once in the laboratory. These water quality measurements include Electrical Conductivity (EC), hardness, the content of Elements Ca, Mg, Na and K, and pH concentrations. The results based on the total area of the crown showed that mahogany had an interception value of 18.088%. In the throughfall measurement, the mahogany has a throughfall of 81.799%, while the amount of the stemflow is only 0.113%. The correlation of interception values, throughfall, and stemflow with rainfall are in general positively correlated. That means the higher rainfall water will increase the number of interception, throughfall, and stemflow. The results on water quality measurement explain that Ec value in rainwater interception was increased compared to water produced from rainfall in mahogany trees. It also has the same condition in hardness measurement. In pH measurements, the interception of rainwater has less pH when compared to direct rainfall water. In addition, the content of Elements Ca, Mg, K, and Na in Stemflow and Throughfall water have more numbers than rainfall itself.

Mahogany (Swietenia macrophylla King.) as urban tree: tree growth and wood quality variation in a progeny test

Mahogany (Swietenia macrophylla) is a tree species widely planted not only for timber production but also as a shade tree in urban areas both on the side of the highway (green belt) and other green open areas. The objective of this study was to analyze the genetic variation of growth and wood quality of a mahogany progeny test at the Parung Panjang, Bogor, which will be converted into a seedling seed orchard for high quality seed production. The progeny test was established using a randomized complete block design involving 96 families originating from seven populations (land races) in Java Island, i.e., Cianjur, Sumedang, Tasikmalaya, Magelang, Gundih, Madiun, and Jember. The results showed that the family had a significant effect on all the growth and wood quality parameters. Individual and family heritability for all growth and wood quality traits were categorized into the high, i.e., 0.33 - 0.96 and 0.35 - 0.56, respectively. The selection simulation showed that the selection percentage of 44.68% (45 best families) gave the optimum genetic gain based on growth and wood quality traits.

Preliminary Phytochemical Screening and Bioactive Compounds of Swietenia macrophylla Seed Support T1DM and T2DM

The purpose of this study was to investigate the antidiabetic effect of phytocompounds from Swietenia macrophylla seed using preliminary phytochemical screening, invitro antioxidant activity and molecular docking studies. The powdered seed extract of Swietenia macrophylla was to investigate the phytochemical screening exhibited the presence of alkaloid, phenols, tannins, flavonoids, terpenoids, steroids, carbohydrates, amino acids and proteins as major active constituents. The antioxidant activity of Swietenia macrophylla seed was evaluated by DPPH free radical scavenging assay. Rutin was used as a reference compound. The Swietenia macrophylla seed exhibited 56.0471% of free radical scavenging activity as compared with rutin. The molecular docking studies performed by using molecular docking server online respectively in which the antidiabetic target namely glutamine:fructose-6-phosphate amidotransferase (GFAT) (PDB id: 2ZJ3) have a potential interaction with swietenine, swietenolide, β-sitosterol, and fucosterol. In this study, the protein glutamine:fructose-6-phosphate amidotransferase (GFAT) was used from its structure perspectives. Its primary and secondary structures were evaluated using online tools. Its role in antidiabetic was assessed by molecular docking the compounds present in the seed extract of Swietenia macrophylla assayed by GC-MS analysis. This in-silico study demonstrates the interactions of active components of Swietenia macrophylla against Type I and Type II diabetes.