Paper Reviewed
Zhu, X., Song, F., Liu, S. and Liu, F. 2016. Role of arbuscular mycorrhiza in alleviating salinity stress in wheat (Triticum aestivum L.) grown under ambient and elevated CO2. Journal of Agronomy and Crop Science 202: 486-496.

"The aim of this study," in the words of Zuh et al. (2016), "was to investigate the potential role of AM [arbuscular mycorrhiza] fungus in alleviating salinity stress in wheat (Triticum aestivum L.) plants grown under ambient and elevated CO2 concentrations." Thus, they grew plants either inoculated or not inoculated with AM fungus in two glasshouses with air of two different CO2 concentrations (400 and 700 µmol l^-1) and three salinity levels (0, 9.5 and 19.0 dS m^-1). And what did they thereby learn?

The four researchers report that "salinity stress decreased and elevated CO2 increased AM colonization" and that "AM inoculation increased plant dry weight under elevated CO2 and salinity stress" (see table below). They also found that "AM symbiosis improves wheat plant growth at vegetative stages through increasing stomatal conductance, enhancing nitrogen use efficiency, accumulating soluble sugar, and improving ion homeostasis in wheat plants grown at elevated CO2 and salinity stress."

Collectively, therefore, Zhu et al. conclude that their study "for the first time, provides the knowledge about the effects of AM fungi on plant growth and physiological processes under elevated atmospheric CO2 concentrations and salinity stress." And they therefore suggest that "AM symbiosis is an effective strategy to help plants to cope with future climate change scenarios."

Table 1. Root colonization percentage, shoot and root dry weight (DW), and root to shoot dry mass ratio (RSR) of wheat plants inoculated (+M) or not inoculated (-M) with Rhizophagus irregularis (AM) grown at ambient (400 ppm) or elevated (700 ppm) CO2 concentration in combination with 0, 9.5 or 19.0 dS m^-1 NaCl treatments. Values are means ± S.E. Source: Zhu et al. (2016).