Suggest one way in which an increase in the uptake of phosphate could increase plant growth.

Suggest one way in which AMF may benefit from their association with plants.

Scientists investigated the effects of different AMF species on the productivity of the plant community of a prairie grassland ecosystem when growing in/on soil containing different phosphate concentrations.

The scientists set up identical plots of prairie grassland soil containing seeds of the plant species found in the ecosystem. The scientists added different AMF species and different concentrations of phosphate to particular plots. Control plots without AMF species were also set up. After 20 weeks the scientists determined the shoot biomass for each plot.

Explain why an increase in shoot biomass can be taken as a measurement of net primary productivity.

Using the data from Figure 5, evaluate the effect on plant productivity of adding AMF species and adding phosphate to the soil.

Using the ex button on your calculator, determine the rate of shoot biomass production in grams per day for the control plot in soil with normal phosphate concentration.

Answer ______________ g day–1