Letalidad de hongos entomopatogenos sobre Dysdercus peruvianus (Hemiptera: Pirrhocoridae)

Abstract

ResumenSe evaluó la patogenicidad y virulencia sobre Dysdercus peruvianus de una cepa de Acremonium y una AbstractWe assessed the pathogenicity and virulence on Dysdercus peruvianus with a strain of Acremonium and one of Scopulariopsis isolated from infected adult D. peruvianus from Mala, Cañete, south of Lima. A strain of Beauveria sp., isolated from Schistocerca piceifrons peruviana from Ayacucho, was also evaluated. Bioassays were conducted on the fourth instar nymphs of D. peruvianus, and the concentrations used were 3,7 x108 , 1,9 x10 8 , 9,4 x10 7 conidia / mL for Beauveria sp., Acremonium sp. and Scopulariopsis sp. respectively. At 20 days after treatment, the highest mortality rates were caused by Beauveria sp. (83,3%) and Acremonium sp. (80%). Scopulariopsis sp. caused a mortality of 23,3%. Acremonium sp. was the more aggressive strain with a lethal time (LT50) of 3,8 days.

Isolation of Beauveria bassiana Pr-11 from Andean orthopterans and its effectiveness against Chagas disease vectors in Peru

“…This strain has been found as a result of a long-term search for entomopathogenic fungi from different insect hosts, conducted by our team since 2003. At the same environmental conditions, we have previously showed that a 10 8 concentration of the Pr-11 strain was effective against the cotton pest Dysdercus peruvianus (Hemiptera:Pyrrhocoridae), reporting a LT50=5,6 days and 19,2 days and outperforming other 50 fungal isolates (Falconi et al, 2010). Similarly, Pariona et al (2007) showed promising results of this strain against S. piceifrons, at a 10 8 conidial concentration, resulting in a LT50=8.34 and LT80=9.6 days.…”

“…In this study, we present a highly virulent B. bassiana Pr-11 strain isolated from Schistocerca piceifrons (Lynch Arribalzaga, 1903) against T. infestans. Our laboratory had previously reported the high mortality induced by this strain in the same species and on pest hemipterans (Falconi et al, 2010). We discuss the importance of the source of this fungal strain and its potential as biocontrol agent.…”

EN PRENSA Efectividad de una cepa nativa de Metarhizium pinghaense sobre larvas de Triodonyx lalanza Saylor (Coleoptera: Melolonthidae), bajo condiciones semicontroladas. EN PRENSA

“…Por otro lado, el mayor porcentaje de mortalidad efectuado por parte de la cepa nativa MGCPh4, en comparación con la cepa comercial Fungizium ® , puede deberse a los diferentes grados de virulencia de cada hongo, en relación a su especificidad patógeno-hospedero: es decir, la cepa MGCPh4 al ser aislada de una larva de Phyllophaga como hospedante original tuvo una mayor capacidad para ejercer un mayor control sobre gallinas ciegas, en comparación con la cepa Fungizium ® , la cual se desconoce su hospedero original. En relación con este hecho, Falconi et al (2011) señalan que las cepas de hongos entomopatógenos tienden a mostrar un mayor grado de virulencia, sobre individuos que corresponden con su hospedante original, en comparación con las cepas aisladas de otros grupos taxonómicos. Este mismo fenómeno fue obtenido por Flores et al (2002) quienes al evaluar la efectividad de cepas de hongos contra gallinas ciegas observaron que, los aislamientos obtenidos a partir de larvas de Phyllophaga mostraron mayores índices de mortalidad, en comparación con las cepas que fueron aisladas de huéspedes del orden Lepidoptera y Hemiptera.…”