Open AccessLignocellulose Degrading Capabilities of Sphaerobolus stellatus in Creeping Bentgrass
Author(s) -
BaetsenYoung A.M.,
Kaminski J.E.,
Tien M.
Publication year - 2017
Publication title -
international turfgrass society research journal
Language(s) - English
Resource type - Journals
ISSN - 2573-1513
DOI - 10.2134/itsrj2016.05.0400
Subject(s) - laccase , xylanase , lignin , cellulase , organic matter , agrostis stolonifera , chemistry , botany , peroxidase , biology , food science , cellulose , enzyme , biochemistry , poaceae , organic chemistry
Thatch collapse, caused by Sphaerobolus stellatus (Tode) Persoon, is a new disease of finely managed turfgrasses. Symptoms include dark‐green, circular patches of turf atop degraded organic matter resulting in an indentation of the playing surface. Within a 6‐wk period, S. stellatus reduces organic matter and thatch depth by 21 and 25%, respectively, but the mechanism of thatch reduction has not been defined. To characterize the underlying biochemical processes of thatch collapse, lignin degradation was assessed, and the activities of associated lignocellulose enzymes within the organic matter of turfgrass thatch were quantified. One isolate of S. stellatus was inoculated on creeping bentgrass ( Agrostis stolonifera L.) plugs for 6 wk. Using tetramethylammonium hydroxide (TMAH) thermochemolysis to analyze the fate of lignin from golf course thatch, we found a significant depolymerization of S. stellatus ‐colonized lignin. To understand the broader mechanism responsible for organic matter degradation, we used crude enzyme extracts from one S. stellatus isolate from turf and mulch along with one isolate of a Panaeolina spp. at four time points in 3 mo. Extracts were assayed for Mn‐independent and Mn‐dependent peroxidase, laccase, xylanase, and cellulase activity. Elevated levels of laccase were found in the S. stellatus isolate from turf, and both S. stellatus isolates produced levels of Mn‐independent peroxidases. Both S. stellatus isolates and the Panaeolina spp. isolate exhibited xylanase activity. Cellulase was not verifiably detected. The presence of laccase in S. stellatus from turfgrass, Mn‐independent peroxidase in both S. stellatus isolates, and xylanase in all fungal extracts illustrates a mechanism of organic matter reduction in thatch collapse.