vesicular-arbuscular mycorrhiza

A form of *endotrophic mycorrhiza in which the fungus lives between the cells of the cortex and forms temporary hy-phal projections that penetrate the cortical cells. The projections may simply be swollen vesicles or may consist of finely branched masses called arbuscules. Many grasses and crop plants form such associations and the fungi involved are often species of Pythium or Endogone. When soil nutrients are in short supply plants forming such mycorrhizae fare better than uninfected plants. See also ectotrophic mycorrhiza.