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The fate of biobased and biodegradable cellulose-derived plastics in landfills represents an important topic from economic and environmental points of view. Anaerobic digestion is a cost-effective waste-to-energy technology. The behaviour of six polymer types—that is, cellulose (C), cellulose acetate (CA), viscose (V), nanocellulose (NC), acetate textile (AT), and heteropolysaccharide pectin (P)—was studied under anaerobic batch mesophilic conditions in a landfill leachate for 147 days. The cumulative biogas production was as follows: C>V=CA>>AT>>NC=P. Metagenomic analysis revealed notable variations in the proportion of bacterial and archaeal domains with the highest archaeal abundance in the presence of CA (80.2%) and C (78.5%). At the end of digestion, cellulolytic, hydrolytic, and dehydrogenase activities were measured in the intact samples, as well as the liquid and solid fractions, under aerobic and anaerobic conditions. Cellulolytic activity in P was detected only in the pellet, while in NC, activity was mostly in the supernatant under both aerobic and anaerobic conditions. Scanning electron microscopy and confocal scanning laser microscopy showed a defragmentation and degradation of polymeric substrates as well as microbial colonisation. Based on the results, landfill leachate is appropriate for the anaerobic biodegradation of cellulose-derived polymers; however, the process is polymer specific. [ABSTRACT FROM AUTHOR]

Botrytis is one the most economically important fungal taxa, comprising pathogens that infect a wide range of crops and causing gray mould. Two morphologically indistinguishable species, Botrytis cinerea and B. pseudocinerea, are significant pathogens found in close association in the same niches all over the world. Both species cause the same diseases in many plants; however, their mycelial compatibility in Latvia has not been reported. The aim of this study was to compare the morphological characteristics of B. cinerea and B. pseudocinerea isolates and determine their compatibility based on culturing on potato dextrose agar (PDA) media. A total of 113 isolates with the characteristic colony morphology of Botrytis spp. were obtained from four different host plants: tomato (Solanum lycopersicum), faba bean (Vicia faba), strawberry (Fragaria × ananassa), and cranberry (Vaccinium macrocarpon). The obtained isolates were divided into ten groups based on their morphological traits and hosts, and representatives from each group were chosen for further analyses. Botrytis spp. were identified at the species level using the DNA sequences of three protein-coding genes (RPB2, DNA-dependent RNA polymerase II; HSP60, heat shock protein 60; and G3PDH, glyceraldehyde 3-phosphate dehydrogenase). All ten isolates (five B. cinerea and five B. pseudocinerea) were pathogenic on wounded leaves and stems of ten-week-old tomato plants, and the pathogen was re-isolated and identified to fulfill Koch's postulates. A high degree of phenotypic diversity was observed between and within B. cinerea and B. pseudocinerea. Mycelial compatibility was found to vary depending on the species, particular isolate, and host plant. This is the first report of B. pseudocinerea as a causal agent of gray mould on tomatoes in the Baltic region. [ABSTRACT FROM AUTHOR]