Mycorrhiza ("myco" is Greek for mushroom, and "rhiza" for root) refers to the symbiotic association between certain kinds of fungi and the roots of plants -- literally, it's "root fungus." In this mutualistic relationship, the fungi will colonize plant roots and spread out a microscopic network of filaments underground called "hyphae," thus allowing the plants to soak up more water and nutrients, while taking sugars in exchange.
The hope is that mycorrhizal fungi could one day act as a 'bio-fertiliser' that ultimately replaces the need to mine phosphate from the ground for industrial fertiliser. Finding a replacement for mined phosphate is a critical problem as not only is the resultant fertiliser a pollutant – causing algal growth which chokes water supplies – but the big phosphate mines are now depleted to the point where they are expected to run out in the next 30 to 50 years. Many experts are predicting a 'phosphate crisis'.
We need alternatives to phosphate fertiliser if we are to feed growing populations," said Dr Uta Paszkowski from the University of Cambridge's Department of Plant Sciences.