Propagação vegetativa de Aloysia triphylla (L'Hér. ) Britton em função da concentração de AIB e do comprimento das estacas / Vegetative propagation of Aloysia triphylla (L'Hér. ) Britton according to IBA and length of cuttings

A Aloysia triphylla (L'Hér.) Britton é uma planta medicinal de porte arbustivo com folhas aromáticas que possuem óleo essencial rico em citral. A crescente demanda da indústria farmacêutica e cosmética pelo óleo essencial de A. triphylla promoveram grande interesse sobre o cultivo dessa espécie. A estaquia é um dos principais métodos de propagação devido à dificuldade em obter sementes, e também pela vantagem dos descendentes serem iguais à planta-matriz. O objetivo do trabalho foi avaliar o efeito de diferentes concentrações de AIB e do comprimento das estacas no enraizamento de estacas de A. triphylla. O experimento foi conduzido em ambiente protegido no período de Novembro de 2010 a Janeiro de 2011. O delineamento experimental foi inteiramente casualizado em esquema fatorial onde os fatores foram cinco concentrações de ácido indol butírico (AIB) (mg L-1): 0, 250, 500, 1000 e 1500, e quatro comprimentos de estaca: 4, 6, 8 e 10 cm. As estacas tiveram a base imersa em solução de AIB e foram colocadas para enraizar em substrato comercial Mecplant®. As variáveis analisadas foram: comprimento do sistema radicular, percentagem de estacas enraizadas (%), número de brotações, massa fresca e seca da parte aérea, e massa seca das raízes. Nas condições em que o estudo foi realizado os resultados mostraram que o comprimento das estacas e concentração de AIB afetam o desenvolvimento das estacas, apresentando ajuste quadrático e linear para as variáveis analisadas. As mudas obtidas a partir de estacas com 10 cm e concentração de 1500 mg L-1 de AIB apresentaram a maior percentagem de enraizamento e as maiores médias para o comprimento do sistema radicular, número de brotações, massa fresca e seca da parte aérea.

Aloysia triphylla (L'Hér.) Britton is a medicinal plant shrub with aromatic leaves, which have essential oil rich in citral. The increasing demand of the pharmaceutical and cosmetic industries for the A. triphyllaessential oil provided a greater interest in the cultivation of this species. Cutting is one of the main methods of propagation, due to the difficulty in obtaining seeds and also for the benefit of descendants being equal to the parent plant. The objective of this study was to evaluate the effect of different concentrations of IBA and length of cuttings in the rooting of A. triphylla. The experiment was carried out in a protected environment in the period from November 2010 to January 2011. The experimental design was completely randomized using the factorial design where the factors were five concentrations of indole butyric acid (IBA) (mg L-1): 0, 250, 500, 1000 and 1500, and four lengthsforthe cuttings: 4, 6, 8 and 10 cm. The cutting base was immersed in a solution of IBA and placed into the rooting Mecplant ® commercial substrate. The variables analyzed were: root length, percentage of rooted cuttings (%), number of shoots, fresh and dry weight of the shoots, and dry weight of the roots. Under the conditions in which the study was conducted, the results showed that the length of the cuttings and IBA concentration affect the development of the cuttings, with linear and quadratic adjustment for the variables analyzed. The seedlings of cuttings with 10cm and the concentration of 1500 mg L-1 IBA showed the highest percentage of rooting and the highest averages for length of the root system, number of shoots, fresh and dry weight of the shoots.

Respuesta de la regeneración natural en manglares del Golfo de Urabá (Colombia) a la variabilidad ambiental y climática intra-anual / Natural regeneration response in mangroves of the Gulf of Urabá (Colombia) to the environmental and intra-annual climate variability

The natural regeneration process allows the mangrove forests remain over time. Both, biological and physical factors can affect the establishment and early stages along the development of trees. This study examined the response of natural regeneration of mangroves in the Turbo River delta and El Uno bay (Urabá Gulf, Colombia) to intra-annual environmental variability. We quantified mortality, survival and recruitment of seedlings of three mangrove species, seasonally during one year, in 72 semi-perma-nent sub-plots of 1m². In the sub-plots, the total height and the diameter at the base of the stem of all mangrove seedlings with basal diameter less than 2.5cm were measured. Damage by herbivores was also recorded to each seedling. While Laguncularia racemosa recorded the highest rates of mortality, Rhizophora mangle showed the highest survival rate during the study period, although Avicennia germinans dominated the natural regeneration. Through a Redundancy Analysis these processes were associated to environmental variables such as: Direct Site Factor-DSF (sunlight), sediments input rate, herbivory, distances from mangroves to the river, to inner lakes, and to the coastline. These variables explained 43% of the natural regeneration variation; sedimentation rate was the most important variable, while light was very representative for the R. mangle survival. Based on historical records of precipitation, Turbo River flow rate and associated sediment loads, it was established that during the highest precipitation peak, the survival of all species decreases and during the dry season, when the conditions of flooding and sediments input were lower, it was improved. The results indicated that the sediments input rates and sunlight play an important role in the survival of natural regeneration of evaluated mangrove species.

En los bosques de mangle, tanto factores biológicos como físicos, afectan el establecimiento y los estados tempranos de desarrollo de los árboles y determinan la distribución espacial de las especies. Se evaluó la respuesta de la regeneración natural de los manglares del delta del río Turbo y la bahía El Uno a la variabilidad ambiental y climática intra-anual. Se cuantificaron la mortalidad, la sobrevivencia y el reclutamiento de las plántulas de tres especies, estacionalmente durante un año. Avicennia germinans dominó la regeneración natural, Rhizophora mangle presentó la mayor la supervivencia y Laguncularia racemosa la mayor mortalidad. Estos procesos se asociaron principalmente con el aporte de sedimentos aluviales, la disponibilidad de luz, la herbivoría, la distancia al río, a las lagunas internas y a la línea de costa, las cuales explicaron el 43% de la variación en la regeneración. La sedimentación fue la variable más importante para el reclutamiento de A. germinans, mientras la luz fue muy representativa para la supervivencia de R. mangle. Con base en registros históricos de precipitación, caudales y carga de sedimentos, se estableció que en la época con mayor precipitación se presenta un descenso en la supervivencia, y en la época seca se favorece el balance entre el reclutamiento y la mortalidad. Los resultados indicaron que la precipitación, el aporte de sedimentos y la luz desempeñan un papel importante en el proceso de la regeneración de las especies evaluadas.

Growth rate and ring width variability of teak, Tectona grandis (Verbenaceae) in an unmanaged forest in East Timor

Teak (Tectona grandis) is one of the most valuable timbers in international trade and an important species for tropical forestry. Teak is found on the island of East Timor but no information is available on teak growth from this region. A pure stand planted in 1940-50 in the North of East Timor and left unmanaged was studied. Fifteen trees were sampled in October-November 2003 and stem discs taken at three height levels of its height (1.7m, 9.5m and 18.7m), and cores were collected at DBH. Transverse surfaces of the discs and cores were polished for ring identification. Core cross sections were first digitized and disc cross sections were observed under the microscope. Three randomly selected radii were analyzed in each disc. Ring width measurement and ring counting were done using image analysis software. The distinction between heartwood and sapwood was performed macroscopically by colour difference, and heartwood radius and sapwood width were measured. The relationship between stem and heartwood radius was studied for each disc and heartwood percentage by radius was determined. Radial ring width curves are presented for the different axial positions within the stem, and ring width variability was analyzed. Growth rates were calculated and age-radius relationships were estimated using cumulative growth curves. Growth rings were large and well defined in the juvenile phase, reflecting the specie’s fast-growing character. The year-to-year variation of ring width showed a similar pattern among trees. Mean ring width ranged between 4.3-7.3mm for the first 20 years and 3.3-5.1mm for 30 to 45 years. Pith eccentricity was evident in the lower part of the stem and ring wedging occurred. On average, heartwood represented 84% of the radius and sapwood contained 6 to 11 rings. The age-related variation of ring width and the occurrence in the lower part of the tree stems of eccentricity and wedging rings, highlights the importance of appropriate stand management, particularly regarding basal density distribution over time, whenever optimized timber production is envisaged.

La madera de teca (Tectona grandis L.f.) es una de las más valiosas en el comercio internacional y una especie importante para la silvicultura tropical. La teca se encuentra en la isla de Timor Leste, pero no existe información disponible sobre su crecimiento en esta región. Se estudió una plantación pura no manejada que fue establecida entre 1940 y 1950 en el Norte de Timor Leste. Entre Octubre- Noviembre 2003 se cosecharon 15 árboles y al tronco se les extrajeron discos a tres niveles de altura (1.7m, 9.5m y 18.7 m), y se recolectaron núcleos a la altura del pecho (DAP). El conteo y la medición de los anillos se realizaron mediante el software de análisis de imagen. La distinción entre el duramen y la albura se realizó macroscópicamente por la diferencia de color, y se midieron el radio del duramen y el ancho de la albura. Para cada disco se estudió la relación entre el tallo y radio del duramen y el porcentaje del duramen. Las curvas de variación del ancho de los anillos se presentan para las diferentes posiciones axiales dentro del tronco y se analizó la variabilidad del ancho de los anillos. Las tasas de crecimiento fueron calculadas y las relaciones de radio con la edad se calcularon usando las curvas de crecimiento acumulado. Los anillos de crecimiento eran grandes y bien definidos en la fase juvenil, lo que refleja el carácter de crecimiento rápido de esta especie. La variación en la anchura de los anillos año a año mostró un patrón similar entre los árboles. La anchura media del anillo osciló entre 4.3-7.3mm para los primeros 20 años y 3.3-5.1mm para los de 30 a 45 años. La excentricidad de la médula fue evidente en la parte inferior del tallo y se observó la formación de anillos sobrepuestos. En promedio, el duramen representó el 84% del radio y la albura mostró entre 6 y 11 anillos. La variación del ancho de los anillos con la edad, la presencia de excentricidad en la parte inferior del árbol y los anillos sobrepuestos pone de relieve la importancia del manejo forestal con particular atención a la distribución de densidad basal en el tiempo, cuando se pretende la producción optimizada de la madera.

Dinámica de polifenoles de “Cedrón” (Aloysia citrodora Palau -Verbenaceae-) en relación al desarrollo foliar / Polyphenol dinamics on “cedrón” (Aloysia citrodora Palau -Verbenaceae-) according to leave development

Leaf infusions from Aloysia citrodora Palau –Verbenaceae-, known as “cedrón” were analyzed in order to establish the possible influence of their development on polyphenols profile. Chromatographic fingerprints of infusions from young and full expanded leaves were performed and total phenols, total tannins, total flavonoids and total hydroxycinnamic acids were quantified. Young leaves had significative higher total phenols, total flavonoids and total hydroxycinnamic acids concentrations than full expanded leaves. This research suggest that the analyzed parameter should be considered when elaborating products from “cedrón” leaves, as the variation in compound concentration may translate in different biological activities.

Se analizaron las infusiones realizadas a partir de las hojas de Aloysia citrodora Palau –Verbenaceae-, conocida vulgarmente como “cedrón”, con el objeto de establecer la influencia del grado de desarrollo foliar en el perfil de polifenoles. Se obtuvieron los perfiles cromatográficos y se cuantificaron los fenoles totales, taninos totales, flavonoides totales y ácidos hidroxicinámicos totales provenientes de los extractos acuosos de las hojas jóvenes y adultas. Se observaron diferencias cuali-cuantitativas en el perfil de polifenoles cuando se comparan las hojas jóvenes con las hojas adultas. En las hojas jóvenes, las concentraciones de fenoles totales, flavonoides totales y ácidos hidroxicinámicos totales resultaron ser significativamente superiores a las determinadas en las hojas adultas. Los estudios realizados sugieren que la variable aquí analizada debe ser considerada al momento de elaborar productos en base a hojas de cedrón, dado que las diferentes concentraciones detectadas podrían traducirse en diferentes actividades biológicas.

Estacas de diferentes diâmetros na propagação de Lippia alba (Mill.) N.E.Br. - Verbenaceae / Different diameters of cuttings on the propagation of Lippia alba (Mill.) N.E.Br. - Verbenaceae

Este trabalho teve por objetivo avaliar o efeito de diferentes diâmetros de estacas na propagação de Lippia alba. Foram testadas estacas de 25 cm de comprimento, com diâmetros de 0,3-0,5 cm; 0,6-0,9 cm e 1-1,2 cm. Aos 30 e 60 dias após o plantio das estacas foram determinadas as características biométricas, como porcentagem de enraizamento, número de brotos, comprimento dos brotos, massas secas de brotos, estacas, raízes e total. Todos os diâmetros de estacas apresentaram altas taxas de enraizamento aos 30 dias, comprovando que a L. alba é uma espécie de fácil propagação por estaquia. A produção de mudas de L. alba deve ser realizada com estacas entre 1-1,2 cm de diâmetro, que foi superior aos outros diâmetros testados na maioria das características biométricas determinadas.

The aim of this work was to study the effect of different diameters of cuttings on the propagation and growth of Lippia alba. Cuttings of 25 cm length, with three different diameters: 0.3-0.5 cm, 0.6-0.9 cm and 1-1.2 cm, were tested. At 30 and 60 days after the planting of cuttings, the following biometric parameters were determined rooting percentage; number of buds, length of buds; dry matter of buds, cuttings and roots; and total dry matter. All diameters of cuttings presented high rates of rooting after 30 days, confirming that L. alba is an easy-to-root species. L. alba seedling production should use cuttings between 1-1.2 cm diameter, which was better than the others diameters considering most of the tested parameters.

Produção de mudas de Aloysia gratissima (Gillies & Hook. ) Tronc. por meio da propagação sexuada e assexuada / Aloysia gratissima (Gillies & Hook. ) Tronc. seedling production through sexual and asexual propagation

A alfazema-do-Brasil é planta de importância medicinal, como produtora de terpenos. A principal descrição etnofarmaco-botânica aponta como sendo eficaz para infecções brônquicas, pulmonares e da bexiga. O objetivo do trabalho foi estudar a propagação de A. gratissima visando a obtenção de mudas. Na propagação sexuada estudou-se a influência da temperatura na presença e ausência de luz e três épocas de coleta das sementes (março, junho e setembro). Na propagação via semente foram testados três diferentes substratos (areia, palha de arroz carbonizada, Plantmax®). Na propagação vegetativa foram testados dois tipos de estacas (herbáceas e semi-lenhosas) e de dois substratos (areia e Plantmax®). Os resultados indicaram que na propagação sexuada, a germinação das sementes foi maior nas temperaturas constantes de 20 e 25°C, e a melhor época de coleta de sementes foi em março. O substrato comercial mostrou-se superior para o crescimento das plântulas, atingindo 93,25 por cento de emergência das sementes e 100 por cento de sobrevivência. Para a propagação assexuada, as estacas herbáceas em substrato comercial e areia apresentaram 96 e 95 por cento de enraizamento, respectivamente.

Brazilian-lavender is a medicinally important plant since it produces terpenes. As regards ethnopharmacology, it is mainly efficient against bronchial, lung and bladder infections. The aim of this work was to study Aloysia gratissima propagation for seedling production. In sexual propagation, temperature influence in the presence and absence of light and three seed harvesting times (March, June, and September) were studied. Three different substrates (sand, carbonized rice husk, Plantmax®) were also evaluated for seed germination. In vegetative propagation, two cutting types (herbaceous and semihardwood) and two substrates (sand, Plantmax®) were tested. Seed germination was higher under constant temperatures of 20 and 25ºC, and March was the best seed harvest time for sexual propagation. The commercial substrate was the best for seedling growth, peaking 93.25 percent seedling emergency and 100 percent survival. For asexual propagation, herbaceous cuttings in the commercial substrate and sand presented 96 percent and 95 percent rooting, respectively.

Micropropagation of Glandularia perakii Cov. et Schn. (Verbenaceae), a native species with ornamental potential

Glandularia perakii is a perennial species with beautiful violet flowers that grows in the stony soil of Mendocine pedemont. A plentiful and prolonged flowering confers it an important ornamental potential. In this paper, a method of propagation of G. perakii from nodal segments is reported. Proliferating microshoot cultures were obtained by placing nodal segment on Murashige and Skoog medium (MS) supplemented with 20 g.L-1 of sucrose without growth regulators. In this medium multiplication rate after 20 days was 7.9. Rooted plants were acclimatized successfully.