Novel approach for alleviation of soil water repellency using a crude enzyme extract from fungal pretreatment of switchgrass

Soil water repellency (SWR) caused by organic coatings on soil particles can lead to serious loss in crop production and turfgrass quality. In laboratory experiments, we tested the novel concept of direct application of enzymes to alleviate SWR. In a biofuel research project on fungal pre-treatment of switchgrass (Pemicum virgatum L.) for improved saccharification, enzymatic co-products (mainly laccase mixed with other trace enzymes) were produced based on fermentation periods of 18, 36, 54, and 72 days. We characterised enzyme activities of the 18-72-day crude enzyme extracts (CEE) and applied undiluted or diluted solutions (dilutions of 5-, 10-, and 100-fold) to eight air-dried, SWR soils from several golf courses. These soils exhibited water drop penetration times (WDPT) of 345-7439 s (i.e. moderately to very strongly hydrophobic) and all showed a large decrease in SWR to WDPT Additional keywords: soil water repellency, laccase, Co-product, bioremediation.
Introduction Soil water repellency (SWR) is the phenomenon in which a soil does not spontaneously wet when a drop of water is applied to the surface, indicating that the soil [...]