Genomic insights of the genes in kenaf ( L.) reveal that improves the plant's tolerance to the salinity stress.

The WRKY transcription factors (TFs) are among the most diverse TF families of plants. They are implicated in various processes related to plant growth and stress response. Kenaf ( L.), an important fiber crop, has many applications, including the phytoremediation of saline-alkaline soil. However, the roles of WRKY TFs in kenaf are rarely studied. In the present study, 46 kenaf WRKY genes were genome-widely identified and characterized by gene structure, phylogeny and expression pattern analysis. Furthermore, the gene was functionally characterized in under salinity and drought stresses. HcWRKY44 is a nuclear-localized protein that is positively induced by salinity and drought, with roots showing maximum accumulation of its transcripts. Under NaCl and abscisic acid (ABA) stress conditions, plants overexpressing had higher germination rates, better root growth and increased survival than control plants; however, it did not improve the ability to withstand drought stress. Moreover, ABA signaling genes (, , and ), ABA-responsive genes (, , , , and ), stress-related genes (, , and ), and ionic homeostasis-related genes (, , , and ) were positively induced in transgenic plants under NaCl treatment. These results suggest that improved plant's tolerance to salt stress but not osmotic stress through an ABA-mediated pathway. In summary, this study provides provided comprehensive information about genes and revealed that is involved in salinity tolerance and ABA signaling.