Multi-scale characterisation of cold response reveals immediate and long-term impacts on cell physiology up to seed composition in sunflower.

Abstract

Early sowing can help summer crops escape drought and can mitigate the impacts of climate change on them. However, it exposes them to cold stress during initial developmental stages, which has both immediate and long-term effects on development and physiology. To understand how early night-chilling stress impacts plant development and yield, we studied the reference sunflower line XRQ under controlled, semi-controlled and field conditions. We performed high-throughput imaging of the whole plant parts and obtained physiological and transcriptomic data from leaves, hypocotyls and roots. We observed morphological reductions in early stages under field and controlled conditions, with a decrease in root development, an increase in reactive oxygen species content in leaves and changes in lipid composition in hypocotyls. A long-term increase in leaf chlorophyll suggests a stress memory mechanism that was supported by transcriptomic induction of histone coding genes. We highlighted DEGs related to cold acclimation such as chaperone, heat shock and late embryogenesis abundant proteins. We identified genes in hypocotyls involved in lipid, cutin, suberin and phenylalanine ammonia lyase biosynthesis and ROS scavenging. This comprehensive study describes new phenotyping methods and candidate genes to understand phenotypic plasticity better in response to chilling and study stress memory in sunflower.

Plant phenotyping relevance

全身部位のハイスループット画像化と新規フェノタイピング手法が明示され、低温応答の形態評価における手法が中心的に記述されている。

Code and data availability

The paper's plant-phenotyping measurements (morphological, chlorophyll/anthocyanin/flavonoid, root traits, yield and seed composition across 12 experiments) were deposited on Recherche Data Gouv under doi:10.57745/4HNS1J, with a specific sub-dataset (persistentId doi:10.57745/4HNS1J.2598) referenced in Table 1. No code