Transcriptomic and Co-expression Network Analyses on Diverse Wheat Landraces Identifies Candidate Master Regulators of the Response to Early Drought

More than four billion people rely on bread wheat (Triticum aestivum L.) as a major constituent of their diet. However, the changing climate threatens wheat production, with periods of intense drought stress already causing widespread wheat yield losses. Much of the research into the wheat drought response has centred on the response to drought events later in development, during anthesis or grain filling. But as the timing of periods of drought stress become increasingly unpredictable, a more complete understanding of the response to drought during early development is also needed. Here, we utilized the YoGI landrace panel to identify the key genes regulating processes such as, stomatal opening, stomatal closing, stomatal morphogenesis and stress hormone signalling related to drought stress. Fourteen landraces where used to asses the wheat transcriptomic response to drought. The experiment was performed by growing the plant until GS13 (Zadok’s growth scale) and applying the drought stress during 10 days (withhold of water) and three days of recovery (normal watering) after that. Four replicates, per treatment, per landrace accession were used in this experiment. mRNA-Seq analysis was performed on RNA material collected at GS13, and after 10 days of drought stress.