The expansin-like gene StEXLB1 plays a role in potato defence against bacterial wilt

Potato is an important food crop worldwide with high nutritional value. However, infections caused by pathogenic bacteria can significantly reduce yield and tuber quality. Improving the resistance of potato itself is an effective solution. Expansins, a class of plant cell wall proteins, have important functions in mediating responses to both biotic and abiotic stresses. In this study, we identified the expansin-like gene StEXLB1, through transcriptomic screening with deoxynivalenol (DON) as an elicitor, then cloned it and studied it in association with resistance to Ralstonia solanacearum. Subcellular localization revealed that the StEXLB1 protein is localized in the cell wall. We obtained StEXLB1-overexpressing lines and virus-induced gene silencing (VIGS) lines and found that StEXLB1 negatively regulates plant resistance to bacterial wilt. In this study, the function of the expansin-like gene StEXLB1 in resistance to bacterial wilt, was analysed, laying a foundation for the molecular breeding of potato.