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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.