Denny Wiedow

Inoculation with Trichoderma saturnisporum accelerates wheat straw decomposition on soil

Abstract Crop residues such as straw are a favourable habitat of many pathogenic fungi in the soil. Therefore, the undesired accumulation of straw at the soil surface, which occurs regularly in conservation tillage systems, must be mitigated. The present study investigated the effects of an inoculation with the saprotrophic microfungus and potential biocontrol agent Trichoderma saturnisporum on the decomposition of wheat straw. The straw decomposition was investigated indirectly by an aerobic incubation experiment for 13 weeks, and directly by pyrolysis-field ionization mass spectrometry (Py-FIMS). Treatments comprised the addition of glucose, T. saturnisporum and T. saturnisporum with glucose. Soil respiration during the whole incubation period was significantly increased by inoculation with T. saturnisporum. The C/N ratio of the inoculated straw decreased strongly from an initial value of 76 to 43 after 4 weeks and to 30 after 13 weeks. Py-FIMS showed that inoculation with T. saturnisporum caused significant decreases in the sterol content of straw after 4 weeks. Thus, the results demonstrated the potential contribution of T. saturnisporum to accelerate wheat straw decomposition on soil.