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espanolLos polinizadores naturales cumplen un rol importante en la eficiencia reproductiva de Theobroma cacao. El objetivo de esta investigacion fue determinar la cantidad y diversidad de insectos en T. cacao tipo Nacional, en sistema monocultivo y sistema agroforestal, con enfasis en los polinizadores. El estudio se realizo en finca experimental “La Represa” ubicada en el canton Quevedo, provincia Los Rios, Ecuador. Se colocaron trampas de emergencia y captura de insectos en los dos sistemas de cultivo. Ademas, se realizaron observaciones directas en las flores de T. cacao para registrar la presencia de insectos polinizadores. Los insectos capturados se identificaron con la ayuda de claves entomologicas, lupa, y estereomicroscopio. Se calculo el indice de dominancia y diversidad Simpson e indice de similitud de Jaccard. Los mayores porcentajes de insectos se obtuvieron del orden Hymenoptera (76.99%), Coleoptera (10.21%) y Diptera (7.95%). El indice Simpson fue de 0.58 y 0.42 para dominancia y diversidad, respectivamente. La similitud segun Jaccard fue del 24% de las familias de insectos en los sistemas de produccion. Se registro una sola familia (Cecidomyiidae) como un posible polinizador en T. cacao en el area de estudio. Hay baja diversidad y alta dominancia de insectos para los sistemas de produccion analizados. Uno de los factores climaticos que influye en la presencia de los insectos capturados en T. cacao es la humedad relativa, pues se encontro una relacion directa positiva entre estas dos variables EnglishNatural pollinators follow an important role in the reproductive efficiency of Theobroma cacao L. The objective of this research was to determine the quantity and diversity of insects in T. cacao National Type, in monoculture system and agroforestry system, with emphasis on pollinators. The study was carried out in the experimental farm “La Represa” located in the city Quevedo, province Los Rios, Ecuador. Emergency traps and insect capture were placed in the two farming systems. In addition, direct observations were made on the flowers of T. cacao to record the presence of pollinating insects. The captured insects were identified with the help of entomological keys, magnifying glass, and stereomicroscope. The Simpson dominance and diversity index and Jaccard similarity index were calculated. The highest percentages of insects were obtained from the order Hymenoptera (76.99%), Coleoptera (10.21%) and Diptera (7.95%). The Simpson index was calculated at 0.58 and 0.42, and Jaccard’s similarity was 24% among insect families found in both production systems. A single family (Cecidomyiidae) was recorded as a possible pollinator in T. cacao in the study area. There is low diversity and high dominance of insects for the production systems analyzed. One of the climatic factors that influences the presence of the insects captured in T. cacao is the relative humidity, since a positive direct relationship was found between these two variables

The species of Scolytinae subfamily have a worldwide distribution, and are found mainly in the Neo-tropic regions. They usually dominate the communities of wood borer insects. The aim of the present study was to determine the diversity among Scolytinae species associated with balsa, teak, rubber and gamhar plantations located in the humid tropical zone of the Ecuadorian littoral. In each plantation seven flight interception traps containing an ethanol / gel mixture were installed, with a collection frequency of 15 days for three months in the dry period. A total of 1437 specimens were collected, represented by Xyleborini, Cryphalini, Corthylini and Ipini tribes. In the four plantations, 18 species of Scolitids were collected, of which 16 were recorded in the balsa plantation, while in the other plantations 10 to 12 species were found. The most abundant Scolitids were Hypothenemus spp., Corthylus spp., Xyleborus affinis, Xyleborinus bicornatulus and Premnobium cavipennis. The Shannon-Wiener diversity index was higher in the balsa culture (H’= 2.37) and lower in Teak (H’= 1.57). The Jaccard similarity index was higher among the teak and rubber plantations (Cj = 0.9090) while the balsa plantation obtained less similarity with respect to the other three plantations. The greatest diversity of Scolitids was recorded in the balsa plantation, which is a native species, unlike the other forest species, which are exotic, indicating that the diversity would be influenced by the host tree and the location where they are found. The species of Scolytinae subfamily have a worldwide distribution, and are found mainly in the Neo-tropic regions. They usually dominate the communities of wood borer insects. The aim of the present study was to determine the diversity among Scolytinae species associated with balsa, teak, rubber and gamhar plantations located in the humid tropical zone of the Ecuadorian littoral. In each plantation seven flight interception traps containing an ethanol / gel mixture were installed, with a collection frequency of 15 days for three months in the dry period. A total of 1437 specimens were collected, represented by Xyleborini, Cryphalini, Corthylini and Ipini tribes. In the four plantations, 18 species of Scolitids were collected, of which 16 were recorded in the balsa plantation, while in the other plantations 10 to 12 species were found. The most abundant Scolitids were Hypothenemus spp., Corthylus spp., Xyleborus affinis, Xyleborinus bicornatulus and Premnobium cavipennis. The Shannon-Wiener diversity index was higher in the balsa culture (H’= 2.37) and lower in Teak (H’= 1.57). The Jaccard similarity index was higher among the teak and rubber plantations (Cj = 0.9090) while the balsa plantation obtained less similarity with respect to the other three plantations. The greatest diversity of Scolitids was recorded in the balsa plantation, which is a native species, unlike the other forest species, which are exotic, indicating that the diversity would be influenced by the host tree and the location where they are found.

Nothofagus alpina es una de las especies forestales más importantes del Sur de Chile y Argentina, países donde se ha empezado con programas de mejoramiento genético. La micropropagación es una técnica muy útil en la clonación de árboles con fines de mejoramiento, por tanto, los objetivos planteados en esta investigación fueron: determinar la mejor concentración de fitohormonas 6-bencilaminopurina (BAP) y ácido indol butírico (AIB) y, el medio de cultivo idóneo para inducir el enraizamiento de brotes y la brotación de secciones nodales de N. alpina. Se evaluaron los medios de Murashige Skoog (MS) y Wood Plant Medium (WPM), con la mitad de los macronutrientes (enraizamiento) y los micronutrientes completos (multiplicación), suplementado con peptone (0.1%), sacarosa (2.0%), agar (0.7%) y diferentes concentraciones de auxinas. El medio MS suplementado con 2 mg L-1 de AIB resultó mejor para inducir la producción de las raíces, tanto en número como en la longitud de la raíz principal. El mayor porcentaje de enraizamiento se registró en el medio WPM suplementado con 2 mg L-1 AIB. Los tratamientos para inducir multiplicación que incluyeron citoquinina originaron callos y no enraizaron; siendo mayor la presencia de callos en el medio WPM. Se sugiere que la aplicación de citoquininas no es indispensable para la brotación, puesto que en los tratamientos testigos hubo una buena brotación; lo que hace suponer que el material vegetal utilizado tiene suficiente niveles endógenos de esta fitohormona.