Enhanced vermicomposting of leaf litter by white-rot fungi pretreatment and subsequent feeding by Eisenia fetida under a two-stage process

Abstract

Leaf biomass showed rigidity for composting operation due to some structural complexities. To overcome this, leaf litter biomass was pretreated by white-rot Oligoporus placenta for 3-wk firstly and then vermicomposted after mixing in cow dung (1:1 and 2:1 ratio) for 35 d using Eisenia fetida. Fungal pretreatment caused significant loss in lignocellulose (cellulose, 20.60–22.45%, hemicellulose, 16.9–20.4%; lignin, 22.8–25.7%) contents. Pretreated leaf litter vermicomposting caused a significant decrease (%) in cellulose (8.42–10.56), hemicellulose (3.68–8.40), lignin (6.20–8.75), organic C (26.6–31.84), C/N ratio (22.9–35.42), but increase (%) in total N (11.4–138.2), Paval (82.25 to 149.7), and Ca (57.2–85.3) content, significantly (p < 0.05 for all) higher than setups without worms (control). Microbial enzymes activities (proteases, dehydrogenases, β-galactosidase, phosphatase (acid and alkali)) showed better peaks between 7 and 21 d in vermi-setups suggested than control, suggesting earthworm-microbes-mediated mineralization of lignocellulosic biomass into nutrient-rich biomanure. Results suggested that lignocellulosic biomass could be pretreated with rot-fungi before vermicomposting to obtain a quality compost in a short duration.