Uptake of phosphorus-32 by vesicular-arbuscular mycorrhizae

The uptake and accumulation of phosphorus by mycorrhizal and nonmycorrhizal onion plants were compared. The results of the experiments indicate: 1. Mycorrhizal onion plants accumulated significantly more phosphorus in the roots and tops than nonmycorrhizal plants. 2. Vesicular-arbuscular mycrorrhizae are sites of increased phosphorus accumulation compared to nonmycorrhizal roots. 3. A fungitoxicant (parachloronitrobenzene) reduced phosphate accumulation by mycorrhizae but did not significantly affect phosphate accumulation by nonmycorrhizal roots.