Some effects of vesicular-arbuscular mycorrhizas on the nitrogen nutrition of perennial ryegrass (Lolium perenne L.): A dissertation submitted in partial fulfilment of the requirements for the Degree of Bachelor of Agricultural Science (Honours) in the University of Canterbury

Abstract

Vesicular-arbuscular {VA) mycorrhizas are widespread in nature, occurring on more plant species than any other form of mycorrhiza {Gerdeman, 1975). Their importance in plant nutrition, particularly phosphorus nutrition, is now well established (Mossa, 1973a), and VA mycorrhizas may significantly influence the growth and composition of natural communities in soils of low available phosphorus. Vesicular-arbuscu:lar mycorrhizas have also been found to significantly influence the growth of agricultural crop (Khan, 1975b) and pasture (Crush, 1976) plants~ Different species of mycorrhizal fungi enhance the growth and phosphorus nutrition of the hos·t to varying extents, and inoculation of plants with more efficient species of mycorrhizal fungi would therefore appear profitable.