RT Journal Article SR Electronic T1 Chickpea (Cicer arietinum L.) root system architecture adaptation to initial soil moisture improves seed development in dry-down conditions JF bioRxiv FD Cold Spring Harbor Laboratory SP 2020.09.24.311753 DO 10.1101/2020.09.24.311753 A1 Thibaut Bontpart A1 Ingrid Robertson A1 Valerio Giuffrida A1 Cristobal Concha A1 Livia C. T. Scorza A1 Alistair J. McCormick A1 Asnake Fikre A1 Sotirios A. Tsaftaris A1 Peter Doerner YR 2020 UL http://biorxiv.org/content/early/2020/09/25/2020.09.24.311753.abstract AB Soil water deficit (WD) impacts vascular plant phenology, morpho-physiology, and reproduction. Chickpea, which is mainly grown in semi-arid areas, is a good model plant to dissect mechanisms involved in drought resistance.We used a rhizobox-based phenotyping system to simultaneously and non-destructively characterise root system architecture (RSA) dynamics and water use (WU) patterns. We compared the drought-adaptive strategies of ‘Teketay’ to the drought-sensitive genotype ICC 1882 in high and low initial soil moisture without subsequent irrigation.WD restricted vegetative and reproductive organ biomass for both genotypes. Teketay displayed greater adaptability for RSA dynamics and WU patterns and revealed different drought adaptive strategies depending on initial soil moisture: escape when high, postponement when low. These strategies were manifested in distinct RSA dynamics: in low initial soil moisture, its reduced root growth at the end of the vegetative phase was followed by increased root growth in deeper, wetter soil strata, which facilitated timely WU for seed development and produced better-developed seeds.We demonstrate that RSA adaptation to initial soil moisture is one mechanism by which plants can tolerate WD conditions and ensure reproduction by producing well-developed seeds. Our approach will help in identifying the genetic basis for large plasticity of RSA dynamics which enhances the resilience with which crops can optimally adapt to various drought scenarios.Highlight Root system architecture and water use patterns change dynamically for distinct drought adaptation strategies in chickpea.Competing Interest StatementThe authors have declared no competing interest.ANet photosynthetic CO2 assimilation rate per leaf areaCHAConvex hull areaCTControl conditiondasDays after sowingDMDry massFMFresh massFTFlowering timegsStomatal conductance per leaf areaRARoot areaRGRRoot growth rateRSARoot system architectureR/SRoot/shoot ratioSWCSoil water contentTRmassTranspiration rate per leaf mass unitTWUTotal water useVWCVolumetric water contentWDWater deficitWUWater useWUEWater use efficiencyWURWater use rateΔRADifference in root areaΔSWCDifference in soil water content