With the genomics revolution in full swing, relevant phenotyping
is now a main bottleneck. New imaging technologies
provide opportunities for easier, faster and more informative
phenotyping of many plant parameters. However, it is critical
that the development of automated phenotyping be driven by a
clear framing of target phenotypes rather than by a technological
push, especially for complex constraints. Previous studies
on drought adaptation shows the importance of water availability
during the grain filling period, which depends on traits
controlling the plant water budget at earlier stages. We will
then discuss “cause” and “consequence” in phenotypes. Drawing
on this, a phenotyping platform (LeasyScan) was developed
to target canopy development and conductance traits. Based
on a novel 3D scanning technique to capture leaf area development
continuously and a scanner-to-plant concept to increase
imaging throughput, LeasyScan is also equipped with 1488 analytical
scales to measure transpiration seamlessly. Examples
of the first applications are presented: (i) to compare the leaf
area development pattern of pearl millet breeding material targeted
to different agro-ecological zones, (ii) for the mapping
of QTLs for vigour traits in chickpea, shown to co-map with an
earlier reported “drought tolerance” QTL; (iii) for the mapping
of leaf area development in pearl millet; (iv) for assessing the
transpiration response to high vapour pressure deficit in different
crops. This new platform has the potential to phenotype
traits controlling plant water use at a high rate and precision,
opening the opportunity to harness their genetics towards
breeding improved varieties
