Plasticity of maize (Zea mays L.) roots in water-deficient and nitrogen-limited soil

Abstract

Maize (Zea mays L.), a versatile global crop with diverse application in food, feed, and industry, experiences production challenges due to water deficits and concurrent nitrogen (N) limitations. Maize relies on multiple root types, including primary, seminal, crown, brace roots, and associated lateral roots, to acquire water and nutrients from the soil. These root types exhibit distinct soil water and N uptake capacities, dynamically adjusting their morphological and anatomical traits to optimize resource uptake. This review summarizes the plastic responses of maize roots to soil water deficit, N limitation, and lack of other essential nutrients. In response to water deficit, maize axial roots bend toward regions with higher water availability and produce more lateral roots. Simultaneously, the diameter of the root xylem decreases, facilitating sustained water uptake from dry soil. In response to N limitation, maize increases lateral root length, reduces xylem area, and increases cortical aerenchyma. This review enhances our understanding of maize root adaptability in water-limited and N-poor soils, offering valuable perspectives on optimizing root growth for improved water and N acquisition.