Interplay between auxin and abiotic stresses in maize.

Abstract

Plants display a continuum of responses to abiotic stresses, including sensitivity and tolerance. Classical phytohormones have been implicated in these processes due to the observed changes in growth phenotypes following stress cues. This interplay is often described as the growth-stress trade-off. Recent studies have examined abiotic stress responses in maize and implicated auxin biosynthesis, transport, and signaling. However, very few auxin pathway genes have been functionally characterized for their role in stress responses in maize, leaving a large knowledge gap in the field. In this review we will describe our current understanding of relationships between auxin and a myriad of stresses, including temperature, drought, salinity, light, and heavy metals. Resilience to environmental stresses is critical for informing agricultural strategies to improve maize yield and quality. We conclude with a discussion of possible future directions and approaches that may increase our understanding of how auxin mediates growth-stress trade-offs in maize.