Formation and germination of resting spores from different strains from the Entomophthora muscae complex produced in Musca domestica

2001 ◽  
Vol 79 (9) ◽  
pp. 1076-1082 ◽  
Author(s):  
Lene Thomsen ◽  
José Bresciani ◽  
Jørgen Eilenberg
Keyword(s):  
Musca Domestica ◽  
House Fly ◽  
Spore Production ◽  
Spore Formation ◽  
Entomophthora Muscae ◽  
Resting Spore ◽  
Resting Spores ◽  
Group B ◽  
Different Strains

Three species within the Entomophthora muscae (Cohn) Fresenius complex (Entomophthora schizophorae Keller & Wilding, E. muscae s.str., and E. muscae "group B") were investigated for resting spore formation in vivo in the house fly (Musca domestica L.). Resting spores of E. muscae group B were experimentally induced from August to the beginning of February, while no resting spores were ever observed in E. schizophorae infected M. domestica or in flies infected by E. muscae s.str. originating from M. domestica. When newly dead fly cadavers containing E. muscae group B resting spores were kept moist, cystidia emerged from the abdomen; this is the first report of cystidia in the genus Entomophthora. Resting spore production was significantly affected by both temperature and E. muscae group B strain. More infected flies formed resting spores when kept 1 week at 10°C compared with constant exposure at 22°C, but the tendency of the different E. muscae group B strains to form resting spores persisted with shifting temperatures. After 4 months of incubation under natural winter conditions in Denmark, E. muscae group B resting spores germinated on water agar at 20°C with a 16 h light : 8 h dark photoperiod within 1 week, but no germ conidia were observed.Key words: Entomophthorales, Entomophthora muscae complex, Diptera, Musca domestica, resting spore formation, resting spore germination.

Factors affecting the production of resting spores by Zoophthora radicans in the spotted alfalfa aphid, Therioaphis trifolii f. maculata

1989 ◽  
Vol 67 (3) ◽  
pp. 848-855 ◽  
Author(s):  
Travis R. Glare ◽  
Richard J. Milner ◽  
Graham A. Chilvers
Keyword(s):  
Indirect Evidence ◽  
Spore Production ◽  
Factors Affecting ◽  
Resting Spore ◽  
Solid Media ◽  
Number Of Factors ◽  
Resting Spores ◽  
Saturated Atmosphere ◽  
Zoophthora Radicans ◽  
Genetic Combination

Resting spore production by Zoophthora radicans (Brefeld) Batko in infected cadavers of the spotted alfalfa aphid, Therioaphis trifolii (Monell) f. maculata, varied according to a number of factors. For four isolates of the fungus tested, the proportion of cadavers containing resting spores was consistently greater at 10 °C than at higher temperatures. At 20 °C, a saturated atmosphere (100% RH) favoured resting spore production, and the proportion of infected cadavers that contained resting spores was nearly twice the amount of that at 95% RH. Individual isolates of the fungus were found to differ in their ability to form resting spores in infected cadavers; some formed resting spores in few or no cadavers, whereas others formed resting spores in many, under similar conditions. The ability to produce resting spores sometimes varied following serial culturing on solid media. Interestingly, resting spore production was found to correlate with inoculum density. Also, inoculation of aphids with two fungal isolates resulted in a marked increase in resting spore production compared with that of either isolate alone. It is presumed that some form of genetic combination is involved. Indirect evidence suggests that this is more likely to be cytoplasmic than nuclear in origin.

First report of Pandora neoaphidis resting spore formation in vivo in aphid hosts

2012 ◽  
Vol 116 (2) ◽  
pp. 196-203 ◽  
Author(s):  
Ana Clara Scorsetti ◽  
Annette Bruun Jensen ◽  
Claudia López Lastra ◽  
Richard A. Humber
Keyword(s):  
Spore Formation ◽  
First Report ◽  
Resting Spore ◽  
Pandora Neoaphidis

scholarly journals Entomophthora muscae — moisture as a factor affecting its transmission and conidial germination

2014 ◽  
Vol 16 (1) ◽  
pp. 133-139 ◽  
Author(s):  
John P. Kramer
Keyword(s):  
Microscopical Study ◽  
Conidial Germination ◽  
Dominant Form ◽  
Entomophthora Muscae ◽  
House Flies ◽  
Resting Spores

The role played by moisture in the transmission of <i>Entomophthora muscae</i> and in the germination of its conidia was investigated. A majority of adult house flies exposed to conidial showers that fell upon surfaces covered with droplets of condensation acquired the parasite, while no flies exposed to conidial showers that fell upon dry surfaces did so. A microscopical study of conidial showers showed that germination was practically non-existent on dry surfaces while a vast majority of conidia that fell upon a droplet-covered surface germinated. A method for the <i>in vivo</i> culture of <i>E. muscae</i> was developpd and 11 serial passages of the fungus were achieved. Resting spores rather than conidia became the dominant form produced in the cadavers, and flies in a twelfth group remained unifected.

scholarly journals Abiotic and Biotic Factors Affecting Resting Spore Formation in the Mite PathogenNeozygites floridana

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Vanessa da Silveira Duarte ◽  
Karin Westrum ◽  
Ana Elizabete Lopes Ribeiro ◽  
Manoel Guedes Corrêa Gondim Junior ◽  
Ingeborg Klingen ◽  
...  
Keyword(s):  
Pathogenic Fungus ◽  
Field Studies ◽  
Spore Formation ◽  
Biotic Factors ◽  
Tetranychus Evansi ◽  
Tropical Regions ◽  
Factors Affecting ◽  
Resting Spore ◽  
Resting Spores ◽  
Abiotic And Biotic Factors

Neozygites floridanais an obligate mite pathogenic fungus in the Entomophthoromycota. It has been suggested that resting spores of this fungus are produced as a strategy to survive adverse conditions. In the present study, possible mechanisms involved in the regulation of resting spore formation were investigated in the hostsTetranychus urticaeandTetranychus evansi. Abiotic and biotic factors mimicking conditions that we, based on earlier field studies, thought might induce resting spores in temperate and tropical regions were tested with isolates from Norway and Brazil. A total of 42 combinations of conditions were tested, but only one induced the formation of a high number of resting spores in only one isolate. The Brazilian isolate ESALQ1420 produced a large number of resting spores (51.5%) inT. urticaeat a temperature of 11°C, photoperiod of 10L:14D, and light intensity of 42–46 (μmol m−2 s−1) on nonsenescent plants (nondiapausing females). Resting spores of the BrazilianN. floridanaisolate ESALQ1421 were found at very low levels (up to 1.0%). Small percentages ofT. urticaewith resting spores (0–5.0%) were found for the Norwegian isolate NCRI271/04 under the conditions tested. The percentages of resting spores found for the Norwegian isolate in our laboratory studies are similar to the prevalence reported in earlier field studies.

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