Editorial: Root Adaptations to Multiple Stress Factors

The unfavorable soil (low supply of nutrients, high levels of toxic elements, salinity, compaction) and climatic (drought, waterlogging, high temperature, low temperature) conditions reduce plant and crop productivity (Pereira, 2016). Low fertility soils, and extreme weather events resulting from climate change, are a major threat to global food security (Evans, 2009). Plants have evolved sophisticated adaptive mechanisms to withstand the multiple abiotic stresses to which they are exposed (Lamers et al., 2020).Most studies on plant adaptation to abiotic stress conditions are undertaken by applying a single stress condition and analyzing the different physiological, biochemical and molecular aspects of plant acclimation (Araújo et al., 2015). This contrasts to the conditions that occur in nature where crops and other plants are routinely subjected to a combination of different abiotic stresses (Mittler,2006). A good example of combined soil stress is the co-occurrence of aluminum (Al) toxicity and phosphorus (P) deficiency in acid soils, particularly in the tropics (Rao et al., 2016). An example of a combined climatic stress is the co-occurrence of drought and heat stresses during summer (Hammer et al., 2020). The effect of combined stress factors on crops and plants is not always additive due to the nature of interactions between the stress factors which dictate the final outcome (Mickelbart et al., 2015; Magalhaes et al., 2018).