Sprayable biodegradable mulch

Presentation by Dr Stuart Gordon (CSIRO)

Abstract

Plastic mulch films (PMFs) are widely used in crops to improve water use efficiency, prevent weeds, and increase soil temperature for germination. Currently more than 10 million tons of PMFs are used each year and none is truly biodegradable. There are now long-term negative effects associated with the build-up of plastic mulch residues such as reduced soil porosity and water content, and plant effects such as leaf wilting, dead seedlings, and premature ageing of the crop. All of which cause significant declines in farm productivity. CSIRO has developed a sprayable biodegradable mulch (SBM) to eliminate the use of PMFs, so nothing leaves the farm except healthy crop products. The SBM, based on an aqueous and biodegradable polyurethane emulsion is metabolised within the crop cycle by the soil microbiome leaving no toxic residues. The presentation provides an update on development of the SBM, and recent funding by the Australian Grains Research and Development Corporation to reformulate CSIRO’s SBM so that it can be applied to broadacre agriculture.