Publications by authors named "Larissa Barelli"

Background: Biological control of insect pests is encountering an unprecedented challenge in agricultural systems due to the ongoing rise in carbon dioxide (CO) level. The use of entomopathogenic fungi (EPF) in these systems is gaining increased attention, and EPF as crop endophytes hold the potential for combining insect pest control and yield enhancement of crops, but the effects of increased CO concentration on this interaction are poorly understood. Here, the introduction of endophytic EPF was explored as an alternative sustainable management strategy benefiting crops under elevated CO, using maize (Zea mays), Asian corn borer (Ostrinia furnacalis), and EPF (Beauveria bassiana) to test changes in damage to maize plants from O.

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Metarhizium is a genus of endophytic, insect-pathogenic fungi that is used as a biological control agent. The dual lifestyles of these fungi combine the parasitism of insect pests with the symbiotic association with plant roots. A major class of secreted metabolites by Metarhizium are cyclic depsipeptides called destruxins (DTXs).

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The microbial community in the plant rhizosphere is vital to plant productivity and disease resistance. Alterations in the composition and diversity of species within this community could be detrimental if microbes suppressing the activity of pathogens are removed. Species of the insect-pathogenic fungus, Metarhizium, commonly employed as biological control agents against crop pests, have recently been identified as plant root colonizers and provide a variety of benefits (e.

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The endophytic, insect pathogenic fungus, Metarhizium, exchanges insect-derived nitrogen for photosynthate as part of a symbiotic association similar to well-known mycorrhizal relationships. However, little is known about this nitrogen transfer in soils where there is an abundance of nitrogen and/or carbon. Here, we applied D-glucose and ammonium nitrate to soil to examine the effect on root colonization and transfer of labelled nitrogen (15N) from an insect (injected with 15N-ammonium sulfate) to Metarhizium robertsii, into leaves of the common bean, Phaseolus vulgaris, over the course of 28 days.

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Here we assessed the time course of rhizoplane colonization by the endophytic insect pathogenic fungus Metarhizium robertsii. We describe a method of quantifying root colonization of bean plants by M. robertsii using quantitative polymerase chain reaction (qPCR).

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Metarhizium robertsii is a common soil fungus that occupies a specialized ecological niche as an endophyte and an insect pathogen. Previously, we showed that the endophytic capability and insect pathogenicity of Metarhizium are coupled to provide an active method of insect-derived nitrogen transfer to a host plant via fungal mycelia. We speculated that in exchange for this insect-derived nitrogen, the plant would provide photosynthate to the fungus.

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Zika virus (ZIKV), belonging to the family Flaviviridae, genus Flavivirus, is an arthropod-borne virus that was first discovered from the Zika forest in Uganda in 1947. Recent outbreaks in South America have linked ZIKV to cases of microcephaly and Guillain-Barré syndrome in humans. With the increased interest in ZIKV, protocols must be established to facilitate proper research.

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This review examines the symbiotic, evolutionary, proteomic and genetic basis for a group of fungi that occupy a specialized niche as insect pathogens as well as endophytes. We focus primarily on species in the genera Metarhizium and Beauveria, traditionally recognized as insect pathogenic fungi but are also found as plant symbionts. Phylogenetic evidence suggests that these fungi are more closely related to grass endophytes and diverged from that lineage ca.

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Metarhizium robertsii is an entomopathogenic fungus that is also plant rhizosphere competent. Two adhesin-encoding genes, Metarhizium adhesin-like protein 1 (Mad1) and Mad2, are involved in insect pathogenesis or plant root colonization, respectively. Here we examined the differential expression of the Mad genes when grown on a variety of soluble (carbohydrates and plant root exudate) and insoluble substrates (locust, tobacco hornworm, and cockroach cuticle, chitin, tomato stems, cellulose, and starch) and during insect, Plutella xylostella, infection.

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Insect pathogenic fungi such as Metarhizium anisopliae and Beauveria bassiana have an increasing role in the control of agricultural insect pests and vectors of human diseases. Many of the virulence factors are well studied but less is known of the metabolism of these fungi during the course of insect infection or saprobic growth. Here, we assessed enzyme activity and gene expression in the central carbon metabolic pathway, including isocitrate dehydrogenase, aconitase, citrate synthase, malate synthase (MLS) and isocitrate lyase (ICL), with particular attention to the glyoxylate cycle when M.

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