To screen surfactants suitable for foliar application on Leymus chinensis and capable of enhancing the absorption efficiency of 6-benzylaminopurine （6-BA）， five surfactants （Silwet 408，SDS，MES，DDM，orange） commonly used on hydrophobic leaves of gramineous plants were evaluated based on surface tension， critical micelle concentration， contact angle， and maximum stable retention. The results showed that the leaves of L. chinensis exhibited super hydrophobicity， and the apparent surface free energy at the heading stage was significantly lower than that at the regreening stage（P<0.05）. Polyether-modified silicone Silwet 408 exhibited the optimal performance， achieving the lowest surface tension at the critical micelle concentration （21.27 mN·m^-1） and complete spreading （contact angle <5°） at both growth stages， followed by orange peel essential oil. SDS and orange peel essential oil showed the highest retention at the regreening stage （36.16 mg·cm^-2） and heading stage （34.60 mg·cm^-2）， respectively. Therefore， Silwet 408 is recommended as the preferred surfactant， while orange peel essential oil serves as a green alternative at the heading stage. This study provides a theoretical basis and technical support for efficient delivery of foliar regulators in L. chinensis.

Leymus chinensis  /  Surfactant  /  Foliar application  /  Wetting behavior  /  Plant growth regulators