Soil phosphorus availability is a driver of the responses of maize (Zea mays) to elevated CO2 concentration and arbuscular mycorrhizal colonisation

Research output: Contribution to journalJournal articleResearchpeer-review

  • Stephanie J. Watts-Williams
  • F. Andrew Smith
  • Iver Jakobsen

In the context of a changing climate, there has been an increased research focus on predicting the response of plants to elevated atmospheric CO2 concentrations. Simultaneously, the availability of phosphate fertiliser is becoming increasingly limited. Although the effects of climate change on arbuscular mycorrhizal fungi (AMF) have been given some attention, it has not been possible to generalise effects of AMF confidently across plant functional groups such as C3 and C4 plants. We grew the C4 cereal Zea mays cv. B73 with or without inoculation with the AMF Funneliformis mosseae, at three different soil P concentrations ranging from 0 to 90 mg P kg−1 soil, and at ambient (400 ppm: aCO2) or elevated (900 ppm: eCO2) CO2 concentrations. Plant biomass, shoot P nutrition, and colonisation by AMF were analysed. With limiting soil P, plant growth responded positively to colonisation by AMF, but not eCO2. At the medium soil P treatment, shoot P concentration but not growth was increased by AMF colonisation, while growth was instead increased by eCO2. The positive growth response to eCO2 persisted at the highest soil P treatment, where there were no effects of AMF colonisation on plant growth or P nutrition. The effects of AMF colonisation and CO2 on maize growth and P nutrition in a future climate scenario will likely be highly dependent on the availability of soil P. Furthermore, differential effects on plants of contrasting functional groups (eg., C3 vs C4) should be considered when investigating the role of AMF under eCO2 conditions.

Original languageEnglish
JournalSymbiosis
Volume77
Issue number1
Pages (from-to)73-82
Number of pages10
ISSN0334-5114
DOIs
Publication statusPublished - 15 Jan 2019

    Research areas

  • Arbuscular mycorrhizal symbiosis, C photosynthesis, Elevated atmospheric CO, Plant phosphorus uptake, Soil phosphorus, Zea mays

ID: 213622461