Drought and salt stress in Chrysopogon zizanioides leads to common and specific transcriptomic responses and may affect essential oil composition and benzylisoquinoline alkaloids metabolism

Abstract

Abiotic stresses affect crop productivity worldwide. Understanding molecular mechanisms of plant abiotic stress tolerance is important for developing stress tolerant crop plants for sustaining crop productivity in future. Chrysopogon zizanioides (vetiver) is a perennial C4 grass reported to be tolerant to water, salinity and submergence stress. Here, we subjected C. zizanioides seedlings to salt and drought stress and carried out whole transcriptome profiling of leaf and root tissues. Assessing the global transcriptome changes under drought and salt stress resulted in the identification of several genes contributing to stress response in this species. Overall, more transcriptomic changes were observed in leaf tissue compared to root tissue. The response to either stress manifested primarily as upregulation of gene expression in both leaf and root. The study identified stress responsive genes commonly and differently regulated under stress/tissue conditions. Several DEGs in our data were identified as enzymes involved in biosynthesis of essential oil components. The differential expression of these genes under drought and salt stress may affect the vetiver essential oil composition under these stresses. Similarly, several genes involved in the biosynthesis of benzylisoquinoline alkaloids including morphin were found to be differentially expressing in our data. Our data may facilitate further molecular studies on stress tolerance of C. zizanioides. The DEGs from our results are potential candidates for understanding and engineering abiotic stress tolerance in plants.

Keywords

• Chrysopogon zizanioides
• Drought stress
• Salt stress
• Essential oil
• Benzylisoquinoline alkaloids
• Vetiver