Water stress and mycorrhizal isolate effects on growth and nutrient acquisition of wheat

Arbuscular mycorrhizal (AM) colonized plants often have greater tolerance to drought than nonmycorrhizal (nonAM) plants. Wheat(Triticum durum Desf.), whose roots were colonized with Glomus mosseae (Gms) and G. monosporum (Gmn), were grown in a greenhouse to determine effects of water stress (WS) on shoot and root dry matter (DM), root length (RL), and shoot phosphorus (P), zinc (Zn), copper (Cu), manganese (Mn), and iron (Fe) concentrations and contents. Mycorrhizal colonization was higher in well-watered (nonWS) plants colonized with both AM isolates than WS plants, and Gms had greater colonization than Gmn under both soil moisture conditions. Shoot and root DM were higher in AM than in nonAM plants irrespective of soil moisture, and Gms plants had higher shoot but not root DM than Gmn plants grown under either soil moisture condition. Total RL of AM plants was greater than nonAM plants, but was consistently lower for plants grown with WS than with nonWS. The AM plants had similar shoot P and Mn concentrations as nonAM plants, but contents were higher in AM than in nonAM plants. The AM plants had higher shoot Zn, Cu, and Fe concentrations and contents than nonAM plants. The Gms plants grown under nonWS generally had higher nutrient contents than Gmn plants, but nutrient contents were similar for both Gms and Gmn plants grown under WS. The results demonstrated a positive relationship between enhanced growth and AM root colonization for plants grown under nonWS and WS.