Deep roots, better crops? Investigating root and shoot traits in historical and modern pea genotypes

Summary

The increased interest in using mature peas for human consumption requires the development of new pea cultivars with focus on taste and appearance as well as resilience. We explored a collection of old pea accessions for valuable food quality traits and combined this with investigation of agronomic traits and stress resilience. While clear differences in aboveground morphology have been documented, it remains unclear how these variations extend to root development. Understanding how shoot and root traits are connected is crucial for selecting resilient and productive cultivars. We selected six genotypes for a tube experiment representing different eras of a period of 100 years of breeding. Plants are being grown in 1.5 m tall transparent rhizotubes filled with field soil and equipped with water sensors in two depths to determine soil water content. The selected genotypes differ in leaf morphology. Two treatments will be established before flowering, with one being well-watered and the other drought stressed. Root growth and development will be followed during the season by imaging. In addition, the drought effect on biomass, stomatal conductance and nodule formation and function will be determined. A pilot study only including old accessions revealed significant differences in rooting depth, which is expected to have significant impact on resilience towards drought. We will answer the following questions and present results. Has breeding affected the rooting depth? Does rooting depth correlate with differences in leaf morphology and does deeper/more roots correlate with increased drought resistance?