Wild emmer introgression alters root-to-shoot growth dynamics in durum wheat in response to water stress

Authors

Harel Bacher, The Hebrew University of JerusalemFollow
Feiyu Zhu, University of Nebraska - LincolnFollow
Tian Gao, University of Nebraska-Lincoln
Kan Liu, University of Nebraska - LincolnFollow
Balpreet Dhatt, University of Nebraska-LincolnFollow
Tala Awada, University of Nebraska - LincolnFollow
Chi Zhang, University of Nebraska-LincolnFollow
Assaf Distelfeld, University of Haifa
Hongfeng Yu, University of Nebraska - LincolnFollow
Zvi Peleg, The Hebrew University of Jerusalem
Harkamal Walia, University of Nebraska - LincolnFollow

Document Type

Article

Date of this Version

2021

Citation

Published in Plant Physiology 187 (2021), pp 1149–1162

doi:10.1093/plphys/kiab292

Comments

Copyright © 2021 American Society of Plant Biologists. Published by Oxford University Press. Used by permission.

Abstract

Water deficit during the early vegetative growth stages of wheat (Triticum) can limit shoot growth and ultimately impact grain productivity. Introducing diversity in wheat cultivars to enhance the range of phenotypic responses to water limitations during vegetative growth can provide potential avenues for mitigating subsequent yield losses. We tested this hypothesis in an elite durum wheat background by introducing a series of introgressions from a wild emmer (Triticum turgidum ssp. dicoccoides) wheat. Wild emmer populations harbor rich phenotypic diversity for drought-adaptive traits. To determine the effect of these introgressions on vegetative growth under water-limited conditions, we used image-based phenotyping to catalog divergent growth responses to water stress ranging from high plasticity to high stability. One of the introgression lines exhibited a significant shift in root-to-shoot ratio in response to water stress. We characterized this shift by combining genetic analysis and root transcriptome profiling to identify candidate genes (including a root-specific kinase) that may be linked to the root-to-shoot carbon reallocation under water stress. Our results highlight the potential of introducing functional diversity into elite durum wheat for enhancing the range of water stress adaptation.