Phenotyping for Root Traits

Root system architecture determines crop capacity to acquire water and nutrients in the dynamic and variable soil environment. Increasing attention is paid to searching for optimal root traits to improve resource uptake efficiency and adaptation to heterogeneous soil conditions. This chapter summarises genetic variability and plasticity in root traits relevant to increased efficiency of soil resource acquisition. Approaches available for high-throughput phenotyping of root architecture traits at both laboratory and field scales are critically assessed. The advent of several novel imaging technologies such as X-ray computed tomography coupled with image-analysing software packages offers a great opportunity to non-invasively assess root architecture and its interactions with soil environments. The use of three-dimensional structure–function simulation root models is complementary to phenotyping methods, providing assistance in the crop breeding programmes. We also discuss applications and limitations of these novel visualisation technologies in characterising root growth and the root–soil interactions.

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