Figure 4.35 The typical growth response for an Australian Cassia species to inoculation with arbuscular mycorrhizal fungi. The greater shoot dry weight of the inoculated plants is due to the fungi enhancing plant uptake of phosphorus. There is no benefit for the plant from the fungi at the lowest level of phosphorus as the fungi are also likely limited by phosphorus, but benefit is substantial at low-intermediate phosphorus levels. (Based on Brundrett et al. 1996, data courtesy of David Jasper and Karen Clarke)