| Summary: | The high-affinity potassium transporters (HKT) mediate K<sup>+</sup>-Na<sup>+</sup> homeostasis in plants. However, the function of enhancing low-potassium tolerance in sweet potato [<i>Ipomoea batatas</i> (L.) Lam.] remains unrevealed. In this study, a novel HKT transporter homolog <i>IbHKT-like</i> gene was cloned from sweet potato, which was significantly induced by potassium deficiency stress. <i>IbHKT-like</i> overexpressing transgenic roots were obtained from a sweet potato cultivar Xuzishu8 using an <i>Agrobacterium rhizogenes</i>-mediated root transgenic system in vivo. Compared with the CK, whose root cells did not overexpress the <i>IbHKT-like</i> gene, overexpression of the <i>IbHKT-like</i> gene protected cell ultrastructure from damage, and transgenic root meristem cells had intact mitochondria, endoplasmic reticulum, and Golgi dictyosomes. The steady-state K<sup>+</sup> influx increased by 2.2 times in transgenic root meristem cells. Overexpression of the <i>IbHKT-like</i> gene also improved potassium content in the whole plant, which increased by 63.8% compared with the CK plants. These results could imply that the <i>IbHKT-like</i> gene, as a high-affinity potassium transporter gene, may play an important role in potassium deficiency stress responses.
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