Screening Of Cellulose-decomposing Bacteria From Tea Garden Soil And Its Interaction With Earthworm To The Decomposition Of Straw

The decomposition of crops residue,such as tea litter materials and straws,is of fundamental importance for promoting soil quality of tea gardens and producing high-quality tea.However,these crop residues contain a large amount of celulose,which seriously reducing their degradation rate.It has been reported that earthworms and bacterium play a prominent role in acceleratting organic matter mineralization.However,there is a lack of efficient celulose-decomposing bacteria suitable for inoculating in tea garden soil,and the synergistic mechanism between celulose decomposing bacterium and earthworms remains unclear.To fill this gap,we intend to screen high-efficiency celulose decomposing bacteria from typical tea garden soil in Guangdong Province,to explore the synergistic effect of celulose decomposing bacteria and earthworm on straw degradation.Six treaments were set up to investigate the effects of cellulose-decomposing bacterium and earthworms on straw degradation:（1）soil（CK）;（2）inoculated decomposing bacterium in the early stage and inoculated earthworms in the later stage（BE）;（3）only inoculated decomposing bacterium（B）;（4）inoculated earthworms in the early stage and inoculated decomposing bacterium in the later stage（EB）;（5）earthworms and decomposing bacterium were inoculated simultaneously（E+B）;（6）only inoculated earthworms（E）.After 28 days of inoculation,the main results of this study are as follows:1.The degradation rate of filter paper by 4 strains of celulose-decomposing bacteria screened from tea garden soil was more than 15%.2.The inoculation of celulose decomposing bacteria increased the diversity of microorganisms,while the inoculation of earthworms reduced the diversity of microorganisms.3.The degradation rate of celulose and hemicellulose in the system of earthworms-celulose-decomposing bacterium were higher than that in the treatment of only inoculated earthworms or cellulose-decomposing bacterium,of which EB group was the most effective treatment for straw degradation.4.Inoculating celulose-decomposing bacteria or earthworm could stimulate the activity of celulose-decomposing bacteria.Moreover,earthworm-microorganism system has the most obvious activation effect on lignocellulose degrading bacteria.5.Higher total nitrogen content and Cu²⁺concentration would reduce celulose degradation rate,while higher Ca²⁺concentration could increase celulose degradation rate.To some extent,higher Ca²⁺,Mg²⁺and Mn²⁺concentration would increase hemicellulose degradation rate,while higher exoglucanase activity would reduce hemicellulose degradation rate.