Characterization and comparison ofMetarhiziumstrains isolated fromRhynchophorus ferrugineus

Abstract

Rhynchophorus ferrugineus is considered the worst pest of palm species, and few natural enemies are reported for this parasite in its area of origin. Here, we report the first recovery of the entomopathogenic fungus Metarhizium pingshaense associated with R. ferrugineus from Vietnam. The morphological, biochemical, and toxicological features of this strain were studied and compared with those of another Metarhizium strain associated with this weevil in Sicily (Italy), an area of recent introduction. The potential use of these fungi as biocontrol agents was tested against adult insects in laboratory trials and a similar mortality rate was found. Both strains were able to produce toxins and cuticledegrading proteases, but they showed dissimilar enzymatic and toxicological profiles, suggesting a different virulence activity.

Detección de enzimas extracelulares en cepas cubanas del complejo Metarhizium anisopliae con acción entomopatogénica contra Cylas formicarius Fabricius (Coleoptera: Brentidae)

“…Los resultados están en concordancia con lo alcanzado por Reddy et al (2014), quienes al utilizar Metarhizium brunneum Petch para el control de C. formicarius obtuvieron un 100% de mortalidad acumulada a los 5 días. Estos resultados también son similares a lo alcanzado por Cito et al (2014) Durante el bioensayo con la cepa LBM-267, la cual presentó un TL 50 de 3,83 días a la concentración de 1x10 7 conidios/ml, la mortalidad comenzó a registrarse a partir del segundo día, mientras que para las cepas LBM-12 (TL 50 de 7,68 días) y LBM-146(TL 50 de 5,78 días), la mortalidad comenzó a registrarse entre el cuarto y quinto día, respectivamente. El progreso de la infección de LBM-30 y LBM-267 en C. formicarius fue gradual y la esporulación del hongo se expresó de manera marcada a partir de los 7 días.…”

Effect of Beauveria bassiana infection on the feeding performance and antioxidant defence of red palm weevil, Rhynchophorus ferrugineus

“…However, information on the biological control of red palm weevil remains scarce. Laboratory investigations of the infection of red palm weevils with different microorganisms, including nematodes (Gerber and Giblin-Davis 1990;Llácer et al 2009;Dembilio et al 2010a), bacteria (Banerjee and Dangar 1995;Salama et al 2004;Manachini et al 2009), and fungi (Ghazavi and Avand-Faghih 2002;Shaiju-Simon and Gokulapalan 2003;Gindin et al 2006;Dembilio et al 2010b;Cito et al 2014) have shown variable results in terms of larval and adult mortality.…”

“…There have been some scattered reports on the use of entomopathogenic fungi in the control of red palm weevils (Gindin et al 2006;Dembilio et al 2010b;Güerri-Agulló et al 2010Cito et al 2014). However, none of these reports explore host-pathogen interactions between the fungi and the weevil.…”

Red Palm Weevil (Rhynchophorus ferrugineus Olivier, 1790): Threat of Palms

“…Fungi can also affect the RPW fitness, as it is the case of the entomo-pathogenic fungi Beauveria bassiana (Bals.) Vuill, infecting eggs, larvae and adults (El-Sufty et al, 2009), Metarhizium anisopliae (Metchnikoff) Sorokin and Metarhizium pingshaense (Cito et al, 2014). B. bassiana is lethal to the primarily infected weevils and sublethal to other adults in contact with the infected individuals, by lowering their reproductive fitness (Dembilio et al, 2010a;Llacer et al, 2013).…”