Root trait variability in cereal grain crops: potential use in breeding programs to enhance adaptation to water stress

Abstract

Crop root systems directly interact with soil in capturing water and nutrients. Root system architecture and growth has important functional implications for the timing and extent of soil water and nutrient extraction, yet selection for root traits in breeding programs has been limited due to the labour-intensive and costly phenotyping methods for characterizing roots in field crops. The objectives of this research were to identify root traits in key cereals grain crops (maize, sorghum and wheat) that can be potentially employed as candidate traits conferring water stress tolerance. Genotypes within these crops has large variation in different root traits. Root traits such as total root length, root length at various depths, rooting depth, numbers and area of fine roots and nodal root angle. These traits have the potential to serve as functional parameters for plant breeding programs aimed at developing genotypes with improved resource use efficiency and adaptation to adverse environments (e.g., drought stress), enhancing overall crop productivity.