Dynamics of yeast populations recovered from decaying leaves in a nonpolluted stream: a 2-year study on the effects of leaf litter type and decomposition time

Abstract

Here we report on the results of a survey of the yeast populations occurring on submerged leaves (alder, eucalyptus and oak) in a natural mountain stream, during different phases of their decomposition and through two consecutive years. Leaf litter mass loss, total yeast counts, Shannon-Weiner index (H'), yeast community structure and physiologic abilities were analyzed to evaluate the dynamics of yeast communities during decay. Seventy-two yeast taxa were recorded, and in all litter types, species of basidiomycetous affinity predominated over ascomycetous ones. Discriminant analysis of presence/absence data (yeast species) showed significant differences both among substrate types (P<0.0026) and with decomposition time (P<0.0001). Carbon and nitrogen source utilization by yeast strains also varied with the substrate (P<0.0001) and decomposition time (P<0.0001). Further conclusions were that: (1) all litter types have in common ubiquitous yeast species, such as Cryptococcus albidus, Debaryomyces hansenii and Rhodotorula glutinis, among the common 20 yeast species; (2) only a few species were dominant, and most species were rare, being recorded once or twice throughout decomposition; and (3) the order of yeast appearance, and their substrate assimilation patterns, strongly suggest a succession phenomenon. Finally, explanations for the distribution patterns and variations in yeast communities are discussed.

Importance of Saprotrophic Freshwater Fungi for Pollen Degradation

“…These organism are often found in surface waters as saprobes of insects, plants, or leaf litter and sometimes as mycoparasites or pathogens [71]. Their consistent appearance in aquatic studies (e.g., [15], [72]) is peculiar and certainly deserves further attention. Our findings have implications for studies that include different POM size classes.…”

Isolation, identification and characterization of soil microbes which degrade phenolic allelochemicals

“…putida, Ps. nitroreducens and R. glutinis are common microbes in the environments and have been demonstrated to be effective in decomposing and transforming toxic organic compounds (Hinteregger et al 1992;Delneri et al 1995;Heinaru et al 2000;Gonzalez et al 2001;Kwon et al 2003;Margesin et al 2004;Qualls 2005;Sampaio et al 2007;Unno et al 2007). However, the degradation of phenolic allelochemicals in soils by the microbes has not been investigated to a great extent.…”

Winery wastewater treatment by combination of Cryptococcus laurentii and Fenton’s reagent

“…Finally, isolates M33, an Ascomycota (Candida oleophila) and AGG 585, an isolate of basidiomycetous affinity, exhibited the lowest COD removal values. Interestingly, the oxidative Filobasidium, Cryptococcus and Rhodotorula genera, are considered predominant in vineyard environments, such as soil, bark, leaves and grapes (Sabate et al, 2002) and in several litter substrata (Golovchenko et al, 2000;Sampaio et al, 2007;Thormann et al, 2007). However, Cryptococcus and Filobasidum species seemed absent in some WW (Eusébio et al, 2004;Evans and Seviour, 2012), probably due to the fact that these yeasts suffered a strong selective pressure during fermentation (Sabate et al, 2002).…”