Susceptibility of All Nymphal Stages of Bemisia tabaci Biotype B (Hemiptera: Aleyrodidae) to Three Brazilian Isolates of Cordyceps sp. (Hypocreales: Cordycipitaceae) in a Screenhouse Under Variable Temperature and Moisture Conditions.

The susceptibility of 1st to 4th instars of Bemisia tabaci (Gennadius, 1989) (Hemiptera: Aleyrodidae) to three isolates of Cordyceps sp. (Hypocreales: Cordycipitaceae) was evaluated in screenhouse experiments under variable temperatures and moisture conditions. No differences in susceptibility to the Cordyceps sp. isolates were observed among 1st, 2nd, and 3rd instar nymphs with respect to median lethal time (LT50) values. Confirmed mortalities ranged from 63.7 to 87.8% when the isolates were tested at 5 × 107 conidia mL-1. The 4th instar was the least susceptible to the fungal isolates (≤ 36.6% mortality). However, 60.0 to 99.5% of the adults that emerged from 4th instar nymphs previously treated with the fungus succumbed to the infection. Temperature was more detrimental to Cordyceps sp. virulence towards B. tabaci nymphs than relative humidity (RH). At similar RH, median LT50 for 1st instar (9.4 days) was higher than for 3rd instar (5.3 days) when the fungus was tested at 5 × 107 conidia mL-1; minimal temperatures of ≥ 12.6°C compared to ≥ 17.0°C were registered for experiments with 1st and 3rd instars, respectively. However, temperatures ≥ 35°C for 4 to 6 h daily did not affect the efficacy of the fungus against nymphs. Cordyceps sp. showed high virulence to all life stages of B. tabaci at relatively low RH, and an ability to grow extensively over the leaf surface and to produce high amounts of conidia on infected hosts. These attributes certainly boost its potential as an important pest control component of B. tabaci biotype B, especially for management of populations resistant to synthetic insecticides.

Conidiobolus lunulus, a new entomophthoralean species isolated from leafcutter ants.

Entomophthoralean fungi with pathogenic abilities to infect social insects are rare. Here, we describe a fungus isolated from leafcutter ants. Morphologically, the fungus has spherical primary conidia and two types of microconidia: one with the same shape as the primary conidia and another with an elliptical to half-moon shape. The fungus also produces villose conidia known previously only from Conidiobolus coronatus. A multilocus phylogenetic analysis was performed with nuc rDNA sequences from three regions (28S, 18S, and internal transcribed spacer [ITS]). Our isolates are distinguished as a new species, described here as Conidiobolus lunulus, and is more closely related to C. brefeldianus than to C. coronatus, despite the greater morphological resemblance to the latter. Morphological differences, unique phylogenetic placement, and isolation from an altogether new host support this finding. This is the first record of an entomophthoralean species isolated from leafcutter ants.

Characterization of Tolypocladium cylindrosporum (Hypocreales, Ophiocordycipitaceae) isolates from Brazil and their efficacy against Aedes aegypti (Diptera, Culicidae).

AIMS: To survey and to characterize entomopathogenic fungi as natural enemies of mosquitoes in Central Brazil. METHODS AND RESULTS: Tolypocladium cylindrosporum (Hypocreales, Ophiocordycipitaceae) was isolated for the first time in South America by using Aedes aegypti (Diptera, Culicidae) as sentinel larvae in a stagnant mosquito breeding site in a secondary tropical forest. Two isolates were morphologically and molecularly identified, and their activity tested against A. aegypti eggs, larvae and adults. CONCLUSIONS: Findings emphasize the importance of T. cylindrosporum as a natural fungal antagonist of mosquitoes. SIGNIFICANCE AND IMPACT OF THE STUDY: Both isolates affected larvae and adults but were less effective against eggs; both have potential for development as a mycoinsecticide especially against larvae of A. aegypti the main vector of dengue, chikungunya, Zika and urban yellow fever.

First report of Coelomomyces santabrancae sp. nov. (Blastocladiomycetes: Blastocladiales) infecting mosquito larvae (Diptera: Culicidae) in central Brazil.

A project from 2013 to 2017 sought to discover pathogenic fungi and oomycetes from dipteran species that are vectors of major diseases of humans and animals in central Brazil and to begin evaluating the potential of these pathogens as potential biological control agents concentrated on mosquito larvae. Some collecting sites proved to be especially productive for pathogens of naturally occurring mosquito species and for placements of healthy sentinel larvae of Aedes aegypti in various sorts of containers in a gallery forest in the Santa Branca Ecoturismo Private Reserve of Natural Patrimony (RPPN) near Terezópolis de Goiás (GO). Collections during May-April of 2016 and February 2017 yielded a few dead mosquito larvae of an undetermined Onirion sp. (Culicidae: Sabethini) whose hemocoels contained many ovoid, thick-walled, yellow-golden to golden-brown, ovoid thick-walled resistant sporangia, 38.3±4×22.8±2.3µm, decorated by numerous, closely and randomly spaced punctations of variable size and shape. These were the first indisputable collections from Brazil of any Coelomomyces species. Comparisons of the morphology of these sporangia with those of other species of Coelomomyces, confirmed that this Brazilian fungus represented a new species that is described here as Coelomomyces santabrancae.

Neozygites osornensis (Neozygitales: Neozygitaceae) Infecting Cinara sp. (Hemiptera: Aphididae) in Brazil.

The genus Neozygites has been known in Brazil until now only on mites, and this is its first report on aphids in Brazil. Tree-dwelling aphids (Cinara sp.) on a cypress tree were regularly monitored for entomopathogenic fungi in the city of Terezópolis de Goiás in Central Brazil between July 2014 and April 2015. During the survey, mycosed aphids were found attached to twigs. The fungus was identified morphologically as Neozygites osornensis. No in vitro cultures were established from infected aphids. The finding reported here suggests that special attention should be paid in the future for the possible occurrences of Neozygites species wherever cinaran aphids occur around the globe.

Inibição do desenvolvimento de aleurocanthus woglumi ashby (hemiptera: aleyrodidae) por aschersonia cf. aleyrodis webber (deuteromycotina: hyphomycetes)

ABSTRACT The host insects of the fungus Aschersonia sp. are restricted to the Aleyrodidae and Coccidae families of the Hemiptera order. The present study was aimed at evaluating, through bioessays with different concentrations of the fungi, the effect of this fungus, in-vitro, on different developmental stages of Aleurocanthus woglumi, thus testing it as a potential biological control agent. Aschersonia cf. aleyrodis proved more efficient in the control of A. woglumi at higher concentrations, from 2.3 x 107 conidia/mL, turning out to be a good biological control agent of this pest. Although it presented slow growth in the culture medium tested, Aschersonia cf. aleyrodis proved to be efficient in the control of citrus blackfly. The highest mortalities occurred in the youngest stages of A. woglumi as an egg, and at the second and first nymph stages, there being no statistical difference between them. The lowest mortality occurred at the fourth nymph stage. The mortalities at the egg stage, and at the first, second and third nymph stages (but not the fourth), began on the fourth day after A. cf. aleyrodis inoculation, with peaks of mortality on the tenth day.

RESUMO Os insetos hospedeiros do fungo Aschersonia sp. estão restritos às famílias Aleyrodidae e Coccidae, da ordem Hemiptera. Objetivou-se avaliar o efeito, in vitro, desse fungo, nos diferentes estádios de desenvolvimento da mosca-negra-dos-citros, A. woglumi, como potencial agente de controle biológico, através de bioensaios com diferentes concentrações de inóculo do fungo. A melhor eficiência de controle foi constatada em concentrações mais elevadas, a partir de 2,3 x 107 conídios/mL, revelando-se como um bom agente de controle biológico dessa praga. Embora tenha apresentado crescimento lento no meio de cultura testado, Aschersonia cf. aleyrodis mostrou-se eficiente no controle da mosca-negra-dos-citros. As maiores mortalidades ocorreram nas fases mais jovens de A. woglumi como ovo, ninfa 2 e ninfa 1, não havendo diferença estatística entre elas. No estádio de ninfa 4, ocorreu a menor mortalidade. As mortalidades nas fases de ovo, ninfas 1, 2 e 3, com exceção da ninfa 4, se iniciaram no quarto dia após a inoculação de A. cf. aleyrodis, com acmes de mortalidade no 10º dia.

First and southernmost records of Hirsutella (Ascomycota: Hypocreales) and Pandora (Zygomycota: Entomophthorales) species infecting Dermaptera and Psocodea.

We present the first and southernmost records of the fungi Hirsutella strigosa Petch, H. citriformis Speare (Ascomycota: Hypocreales), and Pandora nouryi (Remaudière & Hennebert) Humber (Zygomycota: Entomophthorales) infecting Doru lineare (Eschscholtz) (Dermaptera: Forficulidae), Ectopsocus californicus (Banks) (Psocodea: Ectopsocidae), and Heterocaecilius sp. (Psocodea: Pseudocaeciliidae), respectively. This is the first report of naturally occurring pathogenic fungi infecting Psocoptera, and it is also the first report of P. nouryi from any host outside of the Aphididae. The three fungal species were morphologically described from their host insects and from microscopic preparations. Attempts to obtain pure fungal isolates were unsuccessful but slides and photographs of these fungi were preserved and deposited in mycological collections as herbarium material.

First record of Clonostachys rosea (Ascomycota: Hypocreales) as an entomopathogenic fungus of Oncometopia tucumana and Sonesimia grossa (Hemiptera: Cicadellidae) in Argentina.

Clonostachys rosea (Link: Fries) Schroers, Samuels, Seifert, and Gams (Ascomycota: Hypocreales) has been reported as a mycoparasite of fungi and nematodes and as saprobe in soils, but this fungus has not been reported previously to be entomopathogenic. Many species of cicadellid leafhoppers cause economic damage to crops as vectors of plant pathogens. In the present work, we report the first record of C. rosea as an entomopathogenic fungus of two leafhoppers pest, Oncometopia tucumana and Sonesimia grossa (Hemiptera: Cicadellidae), in Argentina and evaluate the pathogenicity of C. rosea against them.