Decomposition of 14C-labeled cellulose substrates in litter and soil from a beechwood on limestone
1993
Scheu, S. | Wirth, S. | Eberhardt, U.
The decomposition of three different 14C-labeled cellulose substrates (plant holocellulose, plant cellulose prepared from 14C-labeled beech wood (Fagus sylvatica) and bacterial cellulose produced by Acetobacter xylinum) in samples from the litter and mineral soil layer of a beechwood on limestone was studied. In a long-term (154 day) experiment, mineralization of cellulose materials, production of 14C-labeled water-soluble compounds, and incorporation of 14C in microbial biomass was in the order Acetobacter cellulose > holocellulose > plant cellulose in both litter and soil. In general, mineralization of cellulose, production of 14C-labeled water-soluble compounds, and incorporation of 14C in microbial biomass were more pronounced, but microbial biomass 14C declined more rapidly in litter than in soil. In short-term (14 day) incubations, mineralization of cellulose substrates generally corresponded with cellulase and xylanase activities in litter and soil. Pre-incubation with trace amounts of unlabeled holocellulose significantly increased the decomposition of 14C-labeled cellulose substrates and increased cellulase activity later in the experiment but did not affect xylanase activity. The sum of 14CO2 production, 14C in microbial biomass, and 14C in water-soluble compounds is considered to be a sensitive parameter by which to measure cellulolytic activity in soil and litter samples in short-term incubations. Shorter periods than 14 days are preferable in assays using Acetobacter cellulose, because the decomposition of this substrate is more variable than that of holocellulose and plant cellulose.
اظهر المزيد [+] اقل [-]الكلمات المفتاحية الخاصة بالمكنز الزراعي (أجروفوك)
المعلومات البيبليوغرافية
تم تزويد هذا السجل من قبل National Agricultural Library