Effect of entomopathogenic fungi on the control of the coffee berry borer in the laboratory

Among the management and control tactics of the coffee berry borer Hypothenemus hampei (Ferrari), there is the use of entomopathogenic fungi. Due to the importance of prospecting isolates of entomopathogenic fungi for the control of the coffee berry borer, the objective of this study was to evaluate the efficiency of 26 isolates of entomopathogenic fungi in the control of this insect pest in the laboratory. The coffee berry borers were immersed in a solution adjusted to the concentration of 1 to 3 × 108 conidia/mL of each isolate and the control treatment (sterilized water). After seven days total mortality and confirmed mortality were evaluated. The isolates that caused the highest mortality and two commercial isolates were selected for evaluation of lethal concentration (LC50 and LC90) and lethal time (LT50 and LT90). Coffee berry borers were treated at different conidia concentrations for lethal concentration to assess total and confirmed mortality. For a lethal time, the coffee berry borers were treated at the concentration of 108 conidia/mL of the selected isolates, and, after two days and every 24 hours until the eighth day, the number of dead individuals was verified. Among the 26 isolates evaluated, 24 presented mortality higher than the control treatment, and three presented mortality higher than 85%. In the LC50 and LC90 assays, the IBCB 353 and IBCB 364 isolates were more lethal to H. hampei. In the LT50 and LT90 assays, the IBCB 66 and IBCB 353 isolates caused lethality in a shorter time.

Characterization of Two Species of Acremonium (Unrecorded in Korea) from Soil Samples: A. variecolor and A. persicinum

During a survey of fungal diversity of the order Hypocreales in Korea, two Acremonium isolates, CNUFC-1YSRS2-4 and CNUFC-GSNPF3-1, were isolated from soils collected on a bank of the Yeongsan River, Naju, and in a forest on the Mt. Daegak located on Sinsi Island, Gunsan, South Korea, respectively. Based on the morphological characteristics and sequence analysis of the internal transcribed spacer and D1/D2 domains of 28S ribosomal DNA, the isolates CNUFC-1YSRS2-4 and CNUFC-GSNPF3-1 were identified as A. variecolor and A. persicinum, respectively. These 2 species represent novel Hypocreales isolates in Korea.

Evaluación de la virulencia de hongos entomopatógenos del pulgón del ciprés, de dos regiones ecológicas de Chile. II. / Evaluation of the virulence of entomopathogenic fungi of cypress aphid, from two ecological regions of Chile. II

El pulgón del ciprés Cinara cupressi, se considera uno de los insectos invasores más dañinos del mundo, ha provocado una gran mortalidad en especies Cupresáceas nativas y exóticas en varios países. En Chile, fue detectado el año 2003 y para el año 2008 esta plaga ya se encontraba distribuida en todo el país, afectando especies cupresáceas forestales exóticas como Cupressus macrocarpa y especies nativas, tales como, Austrocedrus chilensis (Ciprés de la Cordillera) y Fitzroya cupressoides (Alerce), que están categorizadas en el estado de conservación vulnerable y en peligro respectivamente. El área forestal de Chile ha potenciado y privilegiado el uso de controladores biológicos como parte del manejo integrado de plagas. Es por esto que se ha utilizado el parasitoide Pauesia juniperorum. Sin embargo, se han detectado bajos niveles de parasitismo. Se propone el uso de hongos entomopatógenos como alternativa y complemento al control biológico. Se prospectaron hongos entomopatógenos en la Región ecológica mediterránea per-húmeda y en la Región oceánica con influencia mediterránea. Como resultado se han identificado seis géneros de hongos descritos como patógenos de insectos. Sin embargo, bajo condiciones de laboratorio sólo cepas del género Verticillium fueron virulentas, causando sobre el 80 por ciento de mortalidad acumulada a los 7 días. No hubo diferencias significativas entre las cepas de Verticillium y un producto químico (pirimicarb) aplicado como control, aunque el hongo fue más lento. Las cepas más virulentas fueron identificadas como Verticillium lecanii, Ve 1 y Ve 2, con un TL50 de: 3.2 y 3.1 días y un DL50 : 1.24 y 1.37 conidias mL-1 respectivamente, sugiriendo el uso de estos hongos para controlar C. cupressi en Chile.

The cypress aphid, Cinara cupressi, is considered one of the most important invasive species causing high mortality in exotic and native species of Cupressaceae in several countries in the world. In Chile it was detected in 2003 and in 2008 was distributed throughout the country affecting the exotic forest species Cupressus macrocarpa and the native forest species Austrocedrus chilensis (Ciprés de la Cordillera) and Fitzroya cupressoides (Alerce), both classified as vulnerable and endangered species respectively. Efforts to their management have focused on biological control by using the parasitoid Pauesia juniperorum but until now it has not reached satisfactory control. We propose using entomopathogenic fungi, as alternative and complementary biocontrol. Entomopathogenic fungi were prospected in the ecological region Mediterranean per-humid and in the ecological region Oceanic with mediterranean influence in both colonies of C. cupressi. There were identified six genera of fungi described as insect pathogens. However, in laboratory assays only Verticillium strains were virulent, causing about 80 percent cumulative mortality at seven days. There were not significant differences among strains of Verticillium and chemical (pirimicarb) applied as control, although fungi were slower. The most virulent strains were two Verticillium lecanii, Ve 1 and Ve 2, with an LT50 of: 3.2 and 3.1 days and LD50 : 1.24 and 1.37 conidia mL-1 respectively, suggesting the use of these fungi to control C. cupressi in Chile.

Prospección de hongos entomopatógenos del pulgón del ciprés en dos regiones ecológicas de Chile: I / Prospection of entomopathogenic fungi of cypress aphid in two ecological regions of Chile: I

El pulgón del ciprés (Cinara cupressi), es una plaga exótica distribuida en todo el territorio continental chileno que ha provocado daños importantes tanto enespecies forestales introducidas como nativas. Se han estudiado algunos aspectos de la biología de estepulgón, mediante control biológico y productos químicos, los cuales no presentan actualmente resultadossatisfactorios. Durante el tiempo que esta plaga se ha establecido en Chile, no se ha realizado un estudio sistemático de hongos entomopatógenos asociados aeste pulgón, aunque se cuenta con antecedentes de un control promisorio en pulgones con estos agentes enotros países. Con el objetivo inicial de aislar en una primera fase del presente estudio hongos patogénicospotenciales para el control biológico de C. cupressi, iniciamos su búsqueda en dos regiones ecológicas del sur de Chile (Región ecológica Mediterránea Per-Húmeda y Región ecológica Oceánica con influencia Mediterránea), seleccionándose en cada una de ellas 6sitios de muestreo donde en cada uno se recolectaron 10 ramas con colonias de pulgones que fueron mantenidas en una cámara bioclimática (20 +/- 2 °C, 16:8 h) por 7 días, para estimular el desarrollo fúngico. Se aislaron integrantes de lo géneros Verticillium, Paecilomyces(ambos con mayor frecuencia de presencia), Fusarium y un entomophthoral en estudio.

The cypress aphid (Cinara cupressi) is an exotic plague distributed throughout the Chilean continental territory which has caused significant damage both inintroduced forest species as well as in native ones. Some characteristics as to the biology of this aphid have beenstudied by means of biological control and chemicals yet they have not revealed any satisfactory results up tonow. During the time of occurrence of this plague in Chile systematic study on entomopathogenic fungi associated to this aphid has failed to be accomplishedalthough information about a promissory control in aphids with these agents has been reported in other countries. In order to carry out an isolation of potential pathogenic fungi for the biological control of C.cupressiin the first phase of this present research, we began to look for them in two ecological regions from southernChile (Ecological Mediterranean Per-humid Region and Ecological Oceanic Region having Mediterraneaninfluence). Six sampling sites were selected in each of them while 10 branches infected with aphid colonies were kept in a bioclimatic chamber (20+2ºC, 16:8 h) for 7 days to stimulate fungal growth. Fungi of generaVerticillium, Paecilomyces (both showing the highest occurrence frequency), Fusarium and an entomophtoral under study were isolated.