Gut passage of epigeous ectomycorrhizal fungi by two opportunistic mycophagous rodents

Abstract

Mycophagists can influence fungal diversity within their home ranges by ensuring the continued and effective dispersal of spores from one site to another. However, the passage of spores through the digestive tract of vertebrates can affect the activity and viability of the spores ingested. This phenomenon has been rarely documented in opportunistic mycophagists consuming epigeous fungi. Using laboratory experiments, we investigated the activity and viability of spores of two epigeous ectomycorrhizal fungal species (Laccaria trichodermophora and Suillus tomentosus) after passage through the digestive tract of two opportunistic mycophagous small rodents, the volcano mouse Peromyscus alstoni and the deer mouse P. maniculatus. We found that passage through the gut of either species of rodent had a significant effect on spore activity and viability for both fungal species. The proportion of active spores (0.37-0.40) of L. trichodermophora in the feces of both species of rodents was less than that recorded for the control (0.82). However, the proportion of active spores (0.64-0.73) of S. tomentosus in the feces of each species of rodent was higher than in the control (0.40). On the other hand, the viability of spores was lower (0.26-0.30 in L. trichodermophora and 0.60-0.69 in S. tomentosus) for both fungi when consumed by either rodent relative to the controls (0.90 in L. trichodermophora and 0.82 in S. tomentosus). These findings suggest that these rodent species may be effective dispersers of both epigeous fungi [Current Zoology 57 (3): 293-299, 2011].

Arthropods Vector Grapevine Trunk Disease Pathogens

“…External transport of fungal spores has been established for many plant pathogens (12,18). Internal transport of fungal spores by animals necessitates the excretion of viable propagules in fecal material and has been shown to contribute significantly to fungal dispersal in some systems (22) and may even enhance their germination (5,34). Fecal matter also provides an immediate supply of moisture and nutrients for developing fungal hyphae and can be seen as a concentrated "spore pocket" when compared with dispersal by agents such as wind (5).…”

Micofagia por roedores en un bosque templado del centro de México

“…cuprea, sugiriendo que ambas especies de roedores podrían potencialmente dispersar las esporas de este hongo. El resultado coincide con lo encontrado en otras especies de hongos epigeos, tales como S. tomentosus y L. trichodermophora (Sierra, 2007;Castillo-Guevara et al, 2011;Pérez 2011), consumidas por ambas especies de ratones. Por ejemplo, Pérez (2011) informa que la actividad metabólica esporal de S. tomentosus no disminuyó cuando las esporas pasaron por el tracto digestivo de las 2 especies de ratones, e incluso plántulas de P. montezumae inoculadas con estas esporas presentaron mayores niveles de micorrización que aquellas inoculadas con esporas extraídas directamente del himenio.…”

“…En la misma zona, en el único trabajo previo sobre el tema, Castillo-Guevara et al (2011) demostraron que las esporas de Laccaria trichodermophora y Suillus tomentosus del orden de los Agaricales y Boletales respectivamente, se mantienen activas después del paso por el tracto digestivo de P. maniculatus y P. alstoni. Estos resultados sugieren que estos roedores podrían estar actuando como dispersores efectivos de las esporas de hongos micorrízicos.…”