Effect of ectomycorrhizal fungal species on population growth and food preference of a fungivorous nematode

AbstractTo analyse nematode community structures appropriately for the evaluation of soil ecosystem status and function requires information on the life history traits of K-strategic nematodes. Therefore, a K-strategic fungivorus nematode, Tylencholaimus parvus, was examined for population growth rates on nine fungal species on agar and on soil-based media. Also, the nematode was compared with an r-strategic fungivorus nematode, Aphelenchus avenae, in terms of population growth rates on potato dextrose agar (PDA), and of prey-predator relationships with nematophagus fungi, Pleurotus spp., growing on water agar. Population growth rates of T. parvus on PDA were large on three plant-pathogenic fungi, Botrytis cinerea, Fusarium oxysporum and Phoma herbarum. On the soilbased medium, two saprophytic fungi, Coprinus cinereus and Flammulina velutipes, also supported large population increases of the nematode, as well as F. oxysporum and P. herbarum. Tylencholaimus parvus always had significantly smaller growth rates than A. avenae, and the rates of T. parvus were 0-24% of those of A. avenae on a given fungal species. Tylencholaimus parvus was able to avoid predation of the two Pleurotus species and fed upon the fungal hyphae to reproduce, although A. avenae was killed and consumed by the fungi.

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Mycetophagy in Filenchus misellus (Andrássy, 1958) Lownsbery & Lownsbery, 1985 (Nematoda: Tylenchidae), with notes on its morphology

Nematology ◽

10.1163/156854102760402586 ◽

2002 ◽

Vol 4 (7) ◽

pp. 795-801 ◽

Cited By ~ 28

Author(s):

Ikuo Kadota ◽

Takao Tsukiboshi ◽

Hiroaki Okada

Keyword(s):

Population Growth ◽

Growth Rates ◽

Agaricus Bisporus ◽

Morphological Characteristics ◽

Pythium Ultimum ◽

Fungal Species ◽

Life History Strategies ◽

Population Growth Rates ◽

Species Population ◽

Northern Japan

AbstractPopulation growth rates on fungal colonies and morphological characteristics were investigated in a member of the genus Filenchus (Tylenchidae) collected from decomposing rice straw in Fukushima-city, northern Japan. The nematode was identified as F. misellus on the basis of the great similarity in morphological measurements to the known populations of the species. Population growth rates were measured 40 days after inoculating nematodes on to seven fungal species cultured in Petri dishes at 25oC. Growth rates were high on Chaetomium globosum and Coprinus cinereus, intermediate on Pleurotus ostreatus and Rhizoctonia solani and low on Agaricus bisporus, Fusarium oxysporum and Pythium ultimum. The ability of the nematode to feed on fungi in decomposing organic matter suggests the possibility for alternative life history strategies and greater ecological amplitude for members of Filenchus and other genera of Tylenchidae.

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Phytophagous mites on genetically modified maize with Bacillus thuringiensis genes

Ciência Rural ◽

10.1590/0103-8478cr20160770 ◽

2017 ◽

Vol 47 (10) ◽

Author(s):

Tamara Esteves Ferreira ◽

Marcos Antonio Matiello Fadini ◽

Simone Martins Mendes ◽

Cidália Gabriela Santos Marinho ◽

Ivan Cruz

Keyword(s):

Growth Rate ◽

Population Growth ◽

Population Growth Rate ◽

Food Preference ◽

Insect Pests ◽

Bt Maize ◽

Population Growth Rates ◽

Phytophagous Mites ◽

Maize Cultivars ◽

Two Spotted Spider Mite

ABSTRACT: The study of non-target organisms such as mites, can provide information about the possible effects of transgenic maize cultivars on the arthropod community. This study aimed to evaluate the abundance of phytophagous mites in the area of Bt maize and evaluate the instantaneous population growth rate, and food preference of phytophagous mites on Bt maize. We registered the species occurrence and the number of adult mite individuals on four maize cultivars, one non-Bt 30F35, and three containing the proteins Cry1Ab (30F35 Yg), Cry1F (30F35 Hx) and Vip3a (Impacto Viptera). Cry proteins disrupt the midgut epithelium of insect pests. The food preference and instantaneous population growth rate (ri) were evaluated using the two-spotted spider mite Tetranychus urticae as model. The species Catarhinus tricholaenae and Aceria zeala were recorded. The Bt maize cultivars did not significantly affect the average number of C. tricholaenae and A. zeala mites compared to conventional cultivar. The population growth rates of T. urticae were similar for the different maize cultivars. T. urticae showed no preference between the leaf of Bt or conventional cultivars. Bt maize did not affect the abundance of species in phytophagous mite.

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Feeding Interactions Between Microorganisms and the House Dust Mites Dermatophagoides pteronyssinus and Dermatophagoides farinae (Astigmata: Pyroglyphidae)

Journal of Medical Entomology ◽

10.1093/jme/tjz089 ◽

2019 ◽

Vol 56 (6) ◽

pp. 1669-1677 ◽

Cited By ~ 3

Author(s):

Vit Molva ◽

Marta Nesvorna ◽

Jan Hubert

Keyword(s):

Population Growth ◽

House Dust ◽

Dermatophagoides Pteronyssinus ◽

Mite Species ◽

Fungal Species ◽

House Dust Mites ◽

Dust Mites ◽

Dermatophagoides Farinae ◽

Microbial Species ◽

Feeding Interactions

Abstract The feeding interactions between house dust mites (HDM) and microorganisms are key factors in the survival of mites in human environments. The suitability of different microbes for HDM is not known. Here, microbial species isolated from HDM cultures were offered to HDM in food preference tests under laboratory conditions. The microbial species were added to the rearing diet of mites to reach 7% of Saccharomyces cerevisiae and 10% of each tested microorganism. The suitability of each microbe-supplemented diet for Dermatophagoides pteronyssinus and Dermatophagoides farinae was compared in terms of mite population growth and mite preference in a cafeteria test. The effect of mite feeding on the respiration of microorganisms in the diet was observed in microcosms. HDM were able to feed and reproduce on some bacterial and fungal species, but the suitability of microbial species differed. Increasing the yeast Sa. cerevisiae in the diet from 7 to 17% appeared the most suitable for both mite species. Staphylococcus spp. bacteria were preferred for D. farinae and were suitable for reproduction. The population growth and feeding preferences of D. pteronyssinus and D. farinae with respect to microorganisms indicate that D. farinae can develop on a diet with bacterial (Staphylococcus nepalensis and Staphylococcus kloosii) additions, whereas D. pteronyssinus was successful on a diet with fungal (Aspergillus jensenii and Aspergillus ruber) additions. The bacteria Kocuria rhizophila and Bacillus cereus decreased population growth in D. pteronyssinus, whereas the yeasts Hyphopichia pseudoburtonii, Hyphopichia burtonii, and Candida ciferrii decreased population growth in D. farinae. These results indicate that some microorganisms are an important food source for HDM.

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