Virulence of Isaria sp. and Purpureocillium lilacinum to Rhipicephalus microplus tick under laboratory conditions

Abstract

Rhipicephalus microplus (Canestrini) is an ectoparasite accountable for great economic losses. The use of entomopathogenic fungi to control arthropods has shown promising responses. The present study evaluated the virulence of Isaria farinosa (Holmsk.) Fr., Isaria fumosorosea (Wize) Brown and Smith, and Purpureocillium lilacinum (=Paecilomyces lilacinus) (Thom.) Samson to engorged females, eggs, and larvae of R. microplus. There were four treatment groups (10(5), 10(6), 10(7), and 10(8) conidia ml(-1)) and the control group (water and Tween 80, 0.1% v/v). The treatment was based on immersion of the specimen in 1 ml of the suspension or control solution. The study observed changes in egg viability and larval mortality after treatment. The results showed that I. farinosa, P. lilacinum, and I. fumosorosea caused alterations in the biological parameters of R. microplus ticks. I. fumosorosea presented the greatest potential to control R. microplus engorged females in vitro, causing a 49% decrease in nutritional index. All fungal isolates presented significant reduction in the egg production index. I. farinosa reduced the hatching percentage if the eggs were treated with the two highest conidial concentrations. All conidial concentrations of I. fumosorosea were able to reduce the hatching percentage significantly. All tested isolates showed pathogenicity toward unfed R. microplus larvae. As far as we know, this is the first study reporting the effect in vitro of I. farinosa, I. fumosorosea, and P. lilacinum to different developmental stages of R. microplus ticks.

Susceptibility of adults of the cerambycid beetle Hedypathes betulinus to the entomopathogenic fungi Beauveria bassiana, Metarhizium anisopliae, and Purpureocillium lilacinum

“…This species has been described as being as efficient as the commonly used ne-maticides ( Dube and Smart 1987 , Schenck 2004 , Mendoza et al 2007 , Núñez et al 2012); it is also a controller of insects ( Posada et al 1998 , Suh et al 2002 , Gökçe and Er 2005 , Wakil et al 2012 ) and others arthropods ( Fiedler and Sosnowska 2007 , Shin et al 2011 , Angelo et al 2012 ). According to Bellows (2001) , Headrik and Goden (2001), Lanza et al (2004) , and other authors, the use of entomopathogenic fungi is an excellent method for the biological control of insects.…”

Nutritional effects on the mycelial growth and enzymatic activity ofIsaria farinosa, andHepialuslarvae growth

“…,b; Angelo et al . ). However, the host larvae of O. sinensis are a pest in nature but beneficial to humans after infection of O. sinensis .…”

“…Because it is distributed widely and has a high lethality rate, I. farinosa has been used in biological pest control (Agudelo and Falcon 1983;Chandler et al 1997;Sun and Liu 2008a). Thus, its specific characteristics (Yang et al 2005), including random amplified polymorphic DNA (RAPD), internal transcribed spacers (ITS) and virulence have been well studied (Sun et al 2008b;Cabanillas and Jones 2009;Mochi et al 2010a,b;Angelo et al 2012). However, the host larvae of O. sinensis are a pest in nature but beneficial to humans after infection of O. sinensis.…”

Occurrence of Purpureocillium lilacinum in citrus black fly nymphs

“…It is a parasite of eggs and cysts of Meloidogyne incognita, and other species of nematodes, including Radopholus similis, Heteredora spp., Globodera spp., Rotylenchulus reniformes (KANNAN;VEERAVEL, 2012;CARRION;DESGARENNES, 2012;ALZATE et al, 2012;CASTILLO et al, 2013). In addition, there are also reports of its pathogenicity on some insect species such as Aphis gossypii, Trialeurodes voporariorum, Thrips palmi, Tribolium confusum, Triatoma infestans, and Tetranychus urticae and Rhipicephalus microplus mites (MARTI et al, 2006;FIEDLER;SOSNOWSKA, 2007;WAKIL et al, 2012;ANGELO et al, 2012;HOTAKA et al, 2015;BARRA et al, 2015). Fiedler and Sosnowska (2007), showed the efficiency of P. lilacinum on 3 rd and 4 th instar nymphs of Trialeurodes vaporariorum after 7 days of application of the agent at concentration of 1 x 10 6 spores / mL, causing 84% of nymphal mortality, agreeing with Wakil et al (2012), who reported the effectiveness of the fungus on Aphis gossypii.…”