Identification of HXK Gene Family and Expression Analysis of Salt Tolerance in Buchloe dactyloides

Buchloe dactyloides is one of the typical ecological grass species, characterized by its strong salt tolerance. Hexokinase (HXK) plays a crucial role in plant growth, development, and resistance to abiotic stresses. To understand the function of HXKs in the salt tolerance of B. dactyloides, this study identified and analyzed the HXK gene family members using the whole-genome data of B. dactyloides. Additionally, transcriptomic methods were employed to investigate the expression levels and stress response patterns of the HXK family genes under salt stress. The results showed that 25 HXK genes were identified in the B. dactyloides HXK gene family, which were classified into three subfamilies based on the phylogenetic tree. Members within the same subfamily exhibited similar gene structures and conserved motifs. The promoter regions of BdHXKs contained numerous cis-regulatory elements associated with plant hormone responses, plant growth and development, and resistance to abiotic stresses. Quantitative real-time PCR analysis provided preliminary evidence that the BdHXK5, BdHXK7, and BdHXK23 genes might play important roles in the salt tolerance regulation of B. dactyloides. These findings offer a theoretical foundation for further elucidating the functions and molecular regulatory mechanisms of BdHXKs under salt stress. This study has provided a theoretical basis for the breeding of new varieties of ecological restoration grasses with stronger salt tolerance and better growth and development. This is of great significance for the improvement and ecological restoration of saline-alkali land.