Effects of the entomopathogenic fungi Metarhizium robertsii, Metarhizium flavoviride, and Isaria fumosorosea on the lipid composition of Galleria mellonella larvae

The entomopathogenic fungi Beauveria bassiana, Metarhizium anisopliae, and Isaria fumosorosea were tested against the stored-grain pest Sitophilus oryzae. The fungi were isolated from the soil (from three locations in Attica, Greece: B. bassiana from Tatoion, M. anisopliae from Marathon, and I. fumosorosea from Aghios Stefanos) using larvae of Galleria mellonella as bait. Suspensions of 2.11 × 107 and 2.11 × 108, 1.77 × 107 and 1.77 × 108, and 1.81 × 107 and 1.81 × 108 conidia per ml of B. bassiana, M. anisopliae, and I. fumosorosea, respectively, were applied by three treatments: (i) sprayed on food and set in petri dishes with adults of S. oryzae, (ii) sprayed on adults of S. oryzae and set in petri dishes without food, and (iii) sprayed on adults of S. oryzae and set in petri dishes with food. The observed mortality of S. oryzae adults during the overall exposure period for the lowest, as well as for the highest, concentrations of B. bassiana, M. anisopliae, and I. fumosorosea ranged from 0 to 100%. Concentration was, in most of the cases tested, a critical parameter that determined the “speed of kill” of the exposed insect species for B. bassiana and M. anisopliae. Conversely, concentration was not that critical for I. fumosorosea, and survival was high in some of the combinations tested, even after 14 days of exposure. Both in the highest and the lowest concentrations of fungi, the mortality of S. oryzae adults was higher when the fungi were applied on adults than when they were applied on food. Higher mortality was observed when food was absent than when food was present, in most of the cases tested. The high efficacy levels recorded in the current study indicate that the tested fungi could be effective biocontrol agents against S. oryzae.

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Effect of Soil Chemical Properties on the Occurrence and Distribution of Entomopathogenic Fungi in Portuguese Grapevine Fields

Pathogens ◽

10.3390/pathogens10020137 ◽

2021 ◽

Vol 10 (2) ◽

pp. 137

Author(s):

Lav Sharma ◽

Irene Oliveira ◽

Fátima Gonçalves ◽

Fernando Raimundo ◽

Rupesh Kumar Singh ◽

...

Keyword(s):

Beauveria Bassiana ◽

Entomopathogenic Fungi ◽

Galleria Mellonella ◽

Organic Matter Content ◽

Chemical Properties ◽

Principal Component ◽

Clonostachys Rosea ◽

Total N ◽

Metarhizium Robertsii ◽

Exchangeable K

Entomopathogenic fungi (EPF) contribute to different ecosystem services. However, factors affecting their natural occurrences in soil remain poorly understood. In a previous study, 81 soil samples were subjected to insect baiting using Galleria mellonella and Tenebrio molitor to isolate EPF from Portuguese vine farms. Here, soils yielding any of the four common EPF, i.e., Beauveria bassiana, Purpureocillium lilacinum, Metarhizium robertsii, and Clonostachys rosea f. rosea, were correlated with their chemical properties. Beauveria bassiana was negatively affected by higher available P (p = 0.02), exchangeable K-ions (p = 0.016) and positively affected by higher soil pH_H2O (p = 0.021). High exchangeable K-ions inhibited P. lilacinum (p = 0.011) and promoted C. rosea f. rosea (p = 0.03). Moreover, high available K also suppressed P. lilacinum (p = 0.027). Metarhizium robertsii was inhibited by higher organic matter content (p = 0.009), higher C:N (p = 0.017), total N (p = 0.007), and exchangeable Mg-ions (p = 0.026), and promoted by higher exchangeable Na-ions (p = 0.003). Nonetheless, mean comparisons and principal component analysis suggested that higher soil pH and exchangeable Ca-ions have contrasting effects on EPF occurrences, as they promote B. bassiana and inhibit M. robertsii. Herbicides did not seem to affect EPF presence. Overall, this study is among the first reports on the effects of soil chemistry on EPF other than Metarhizium, and will facilitate biological pest management approaches.

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DNM1, a Dynamin-Related Protein That Contributes to Endocytosis and Peroxisome Fission, Is Required for the Vegetative Growth, Sporulation, and Virulence of Metarhizium robertsii

Applied and Environmental Microbiology ◽

10.1128/aem.01217-20 ◽

2020 ◽

Vol 86 (17) ◽

Cited By ~ 1

Author(s):

Xiangyun Xie ◽

Yulong Wang ◽

Deshui Yu ◽

Rui Xie ◽

Zhenbang Liu ◽

...

Keyword(s):

Entomopathogenic Fungi ◽

Vegetative Growth ◽

Cell Function ◽

Galleria Mellonella ◽

Morphological Changes ◽

Metarhizium Robertsii ◽

Content Type ◽

Cellular Processes ◽

Transport Vesicles ◽

Related Proteins

ABSTRACT Although dynamins and dynamin-related proteins (DRPs), a large GTPase superfamily, are involved in the budding of transport vesicles and division of organelles in eukaryotic cells, the function of these proteins in entomopathogenic fungi has not been reported to date. Here, DNM1, a DRP in Metarhizium robertsii, was characterized using gene disruption and complementation strategies. Mutant phenotype assays showed that the ΔDnm1 strain displayed increased defects in radial growth (∼24%) and conidial production (∼42%) compared to those of the wild type (WT), and reduced conidiation levels were accompanied by the repression of several key conidiation-related genes, including flbA, wetA, and flbD. Additionally, mutant bioassays revealed that disruption of Dnm1 impaired the virulence (both topical inoculation and injection) of M. robertsii in the insect Galleria mellonella. Further analysis demonstrated that deleting Dnm1 in fungi suppressed the transcriptional levels of several virulence genes in the insect hemocoel. Moreover, we found that DNM1 colocalized with peroxisomes and mitochondria. Importantly, disruption of Dnm1 abolished normal fungal endocytosis, resulting in significantly decreased numbers of, as well as morphological changes in, peroxisomes. These findings indicate that deletion of Dnm1 causes significant changes in the vegetative growth, sporulation, and virulence of M. robertsii due to changes in cell function and peroxisomes. IMPORTANCE Dnm1 was found to be involved in fungal development and virulence, mediated peroxisomal fission, and normal endocytosis. This finding provides new insights into the cellular processes and pathogenicity in entomopathogenic fungi.

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Evaluation of the compatibility of entomopathogenic fungi and two botanical insecticides tondexir and palizin for controlling Galleria mellonella L. (Lepidoptera: Pyralidae)

Crop Protection ◽

10.1016/j.cropro.2018.11.012 ◽

2019 ◽

Vol 117 ◽

pp. 20-25 ◽

Cited By ~ 2

Author(s):

Fariba Sohrabi ◽

Fatemeh Jamali ◽

Salim Morammazi ◽

Moosa Saber ◽

Shizuo George Kamita

Keyword(s):

Entomopathogenic Fungi ◽

Galleria Mellonella ◽

Botanical Insecticides ◽

Lepidoptera Pyralidae

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Entomopathogenic fungi in Portuguese vineyards soils: suggesting a ‘Galleria-Tenebrio-bait method’ as bait-insects Galleria and Tenebrio significantly underestimate the respective recoveries of Metarhizium (robertsii) and Beauveria (bassiana)

MycoKeys ◽

10.3897/mycokeys.38.26790 ◽

2018 ◽

Vol 38 ◽

pp. 1-23 ◽

Cited By ~ 8

Author(s):

Lav Sharma ◽

Irene Oliveira ◽

Laura Torres ◽

Guilhermina Marques

Keyword(s):

Functional Diversity ◽

Entomopathogenic Fungi ◽

Insect Pests ◽

Natural Habitat ◽

Habitat Type ◽

Principal Component ◽

Metarhizium Robertsii ◽

Bait Method ◽

Ecological Profiles ◽

Soil Habitat

Entomopathogenic fungi (EPF) are the natural enemies of insect-pests. However, EPF recoveries can be influenced by the soil habitat-type(s) incorporated and/or the bait-insect(s) used. Galleriamellonella (GM) as bait-insect, i.e. ‘Galleria-bait’, is arguably the most common methodology, which is sometimes used solely, to isolate EPF from soils. Insect baiting using Tenebriomolitor (TM) has also been employed occasionally. Here 183 soils were used to estimate the functional diversity of EPF in Portuguese Douro vineyards (cultivated habitat) and adjacent hedgerows (semi-natural habitat), using the TM bait method. Moreover, to study the effect of insect baiting on EPF recovery, 81 of these 183 soil samples were also tested for EPF occurrences using the GM bait method. Twelve species were found in 44.26% ± 3.67% of the total of 183 soils. Clonostachysroseaf.rosea was found in maximum soils (30.05% ± 3.38%), followed by Beauveriabassiana (12.57% ± 2.37%), Purpureocilliumlilacinum (9.29% ± 2.14%) and Metarhiziumrobertsii (6.01% ± 1.75%). Beauveriapseudobassiana (P < 0.001), C.roseaf.rosea (P = 0.006) and Cordycepscicadae (P=0.023) were isolated significantly more from hedgerows, highlighting their sensitivities towards agricultural disturbances. Beauveriabassiana (P = 0.038) and M.robertsii (P = 0.003) were isolated significantly more using GM and TM, respectively. Principal component analysis revealed that M.robertsii was associated both with TM baiting and cultivated habitats, however, B.bassiana was slightly linked with GM baiting only. Ecological profiles of B.bassiana and P.lilacinum were quite similar while M.robertsii and C.roseaf.rosea were relatively distant and distinct. To us, this is the first report on (a) C.cicadae isolation from Mediterranean soils, (b) Purpureocilliumlavendulum as an EPF worldwide; and (c) significant recoveries of M.robertsii using TM over GM. Overall, a ‘Galleria-Tenebrio-bait method’ is advocated to study the functional diversity of EPF in agroecosystems.

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Comparative analysis of the immune response of the wax moth Galleria mellonella after infection with the fungi Cordyceps militaris and Metarhizium robertsii

Microbial Pathogenesis ◽

10.1016/j.micpath.2020.103995 ◽

2020 ◽

Vol 141 ◽

pp. 103995 ◽

Cited By ~ 2

Author(s):

Vadim Yu Kryukov ◽

Natalia A. Kryukova ◽

Oksana G. Tomilova ◽

Yana Vorontsova ◽

Ekaterina Chertkova ◽

...

Keyword(s):

Immune Response ◽

Comparative Analysis ◽

Galleria Mellonella ◽

Cordyceps Militaris ◽

Metarhizium Robertsii ◽

Wax Moth

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Effect of gamma irradiation and/or certain entomopathogenic fungi on the larval Mortality of Galleria mellonella L

Egyptian Journal of Biological Pest Control ◽

10.1186/s41938-018-0099-z ◽

2018 ◽

Vol 28 (1) ◽

Author(s):

Hussein Farid Mohamed ◽

Thanaa Mohamed Sileem ◽

Samira Elsaid Mostafa El-Naggar ◽

Mahmoud Abd El-Mohsen Sweilem ◽

Ahmed Adly Mohamed Ibrahim ◽

...

Keyword(s):

Gamma Irradiation ◽

Entomopathogenic Fungi ◽

Galleria Mellonella ◽

Larval Mortality

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Environmental Tolerance of Entomopathogenic Fungi: A New Strain of Cordyceps javanica Isolated from a Whitefly Epizootic Versus Commercial Fungal Strains

Insects ◽

10.3390/insects11100711 ◽

2020 ◽

Vol 11 (10) ◽

pp. 711

Author(s):

Shaohui Wu ◽

Michael D. Toews ◽

Camila Oliveira-Hofman ◽

Robert W. Behle ◽

Alvin M. Simmons ◽

...

Keyword(s):

Environmental Factors ◽

Pest Management ◽

Beauveria Bassiana ◽

Entomopathogenic Fungi ◽

Galleria Mellonella ◽

Uv Light ◽

Variable Temperature ◽

Environmental Tolerance ◽

Southern Georgia ◽

Lower Tolerance

A new strain of Cordyceps javanica (wf GA17) was observed causing widespread epizootics among whiteflies in Southern Georgia in 2017. The tolerance of conidia to environmental factors including variable temperature and ultraviolet (UV) light was compared between this strain and three commercial strains of entomopathogenic fungi (Metarhizium brunneum F52, Cordyceps fumosorosea Apopka97, and Beauveria bassiana GHA). Under 10–30 °C, C. javanica wf GA17 responded similarly to other fungi, with the highest virulence against Galleria mellonella at 25 °C, followed by 20, 30, and 15 °C; lowest virulence was observed at 10 °C. At 35 °C and 40 °C, C. javanica wf GA17 had lower tolerance than M. brunneum F52 and B. bassiana GHA, but was superior to C. fumosorosea Apopka97 in conidia viability and post-treatment virulence. After exposure to −20 °C for 56 d, C. javanica wf GA17 exhibited lower germination than M. brunneum F52 and lower virulence than M. brunneum F52 and B. bassiana GHA, but higher germination and virulence than C. fumosorosea Apopka97. Following exposure to strong UV light, viability and virulence of all fungi were reduced with increasing exposure periods. Increased environmental tolerance of C. javanica wf GA17 over C. fumosorosea Apopka97 suggests that the new strain could have applicability for commercial pest management.

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Different strategies to kill the host presented byMetarhizium anisopliaeandBeauveria bassiana

Canadian Journal of Microbiology ◽

10.1139/cjm-2017-0517 ◽

2018 ◽

Vol 64 (3) ◽

pp. 191-200 ◽

Cited By ~ 2

Author(s):

Cynthia Barbosa Rustiguel ◽

María Fernández-Bravo ◽

Luis Henrique Souza Guimarães ◽

Enrique Quesada-Moraga

Keyword(s):

Secondary Metabolites ◽

Beauveria Bassiana ◽

Entomopathogenic Fungi ◽

Metarhizium Anisopliae ◽

Galleria Mellonella ◽

Insect Pests ◽

Fungal Growth ◽

Growth Strategy

Studies conducted over the last decades have shown the potential of entomopathogenic fungi for the biocontrol of some insect pests. Entomopathogenic fungi infect their host through the cuticle, so they do not need to be ingested to be effective. These fungi also secrete secondary metabolites and proteins that are toxic to insect pests. In this context, we analyzed the pathogenicity of Metarhizium anisopliae (Metschn.) strains IBCB 384 and IBCB 425 and Beauveria bassiana (Bals.-Criv.) Vuill. strains E 1764 and E 3158 against Galleria mellonella (Linn.) larvae, during pre-invasion and post-invasion phases. The results showed M. anisopliae, especially strain IBCB 384, was most virulent in the pre-invasion phase against G. mellonella, whereas B. bassiana, especially strain E 1764, was most virulent in the post-invasion phase. During in vivo development and in the production of toxic serum, B. bassiana E 3158 was the most virulent. Different fungal growth (or toxin) strategies were observed for studied strains. Metarhizium anisopliae IBCB 425 prioritizes the growth strategy, whereas strain IBCB 384 and B. bassiana strains E 1764 and E 3158 have a toxic strategy. All strains have pathogenicity against G. mellonella, indicating their possible use for biocontrol.

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Influence of pesticides used potatoes control on the growth of entomopathogenic fungi isolated from potatoes fields

Acta Agrobotanica ◽

10.5586/aa.1995.017 ◽

2013 ◽

Vol 48 (2) ◽

pp. 65-73

Author(s):

Ryszard Miętkiewicz ◽

Anna Sapiecha

Keyword(s):

Entomopathogenic Fungi ◽

Metarhizium Anisopliae ◽

Galleria Mellonella ◽

Paecilomyces Fumosoroseus ◽

Copper Oxychloride ◽

Growth Of Fungi

The growth of Metarhizium anisopliae, M.flavoviridae and Paecilomyces fumosoroseus was estimated on Sabouraud's medium to which insecticides and herbicides were added in three doses: A - 10 times higher from recommended field dose, B - as recommended field dose, C - 10 timer lower than recommended. Fungicides were used in B and C doses as well as in dose D - 100 times lower than recomended one. The fungi were obtained from soil under potatoes using Galleria mellonella as bait insect. Chlorothalonil and copper oxychloride were chosen from fungicides, linuron, MCPA, fluazifop-P-butyl and dikwat - from herbicides and deltamethrin, teflubenzuron and fozalon from insecticides. The growth of both species of Metarhizium was stronger inhibited than of Paecilomyces fumosoroseus by fungicides however colonies of Metarhizium always overpassed 50% controls colonies apart from M. flavoviridae on medium with copper oxychloride at concentration B. Herbicide linuron was more toxic to fungi than fungicides. M. anisopliae and M. fluvoviridae did not grow on medium containing dose A and dose B this herbicide but the colonies of P. fumosoroseus at dose B did not overpass 20% of controlled ones. MCPA and fluazifop-P-butyl inhibited fungal colonies in approximated way. On the medium with these herbicides in concentration A fungal colonies were strongly inhibited and the growth of fungi on medium with MCPA at this concentration appeared not before 5 days after inoculation. Dikwat in dose A strongly inhibited the growth of M. anisopliae but in remaining combinations growth of fungal colonies was similar to controlled ones. Fozalon, among insecticides, inhibited the growth of inwestigated fungi strongest. On the medium containing this insecticide in dose A all fungi did not grow, and in dose B colonies of both species of Metarhizium did not overpass 40% of controlled ones. Deltamethrin in dose A and B inhibited the growth of M. anisopliae and M. flavoviridae, but teflubenzuron did not inhibit growth of entomopathogenic fungi at all concentrations.

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