Climate-Smart Maize Breeding: The Potential of Arbuscular Mycorrhizal Symbiosis in Improving Yield, Biotic and Abiotic Stress Resistance, and Carbon and Nitrogen Sink Efficiency

Maize is part of the essential food security crops for which yields need to tremendously increase to support future population growth expectations with their accompanying food and feed demand. However, current yield increases trends are sub-optimal due to an array of biotic and abiotic factors that will be compounded by future negative climate scenarios and continued land degradations. These negative projections for maize yield call for re-orienting maize breeding to leverage the beneficial soil microbiota, among which arbuscular mycorrhizal fungi (AMS) hold enormous promises. In this chapter, we first review the components relevant to maize-AMF interaction, then present the benefits of arbuscular mycorrhizal symbiosis (AMS) to maize growth and yield in terms of biotic and abiotic stress tolerance and improvement of yield and yield components, and finally summarize pre-breeding information related to maize-AMF interaction and trait improvement avenues based on up-to-date molecular breeding technologies.