Strawberry FaEtr2 gene RNAi expression vector construction and genetic transformation

The short hairpin RNA (shRNA) expression vector of the FaEtr2 gene was constructed by inserting the sense fragment into the constructed antisense vector of FaEtr2 (pBI121-Anti-Etr2) in sense orientation. The constructed RNA interference (RNAi) expression vector was transformed into Agrobacterium fumefeciens LBA4404 and used to infect strawberry leaves. Using in vitro plantlet leaves as explants, the transformation conditions of All-Star strawberry were studied systemically. The results showed that infecting the leaves with A. fumefeciens resuspension liquid of OD600 = 1.0 by pre-culturing for 3 d, co-culturing for 3 d, infecting for 10 min, and adding acetosyringone (AS) 50–100 μmol·L−1 was suitable for genetic transformation of All-Star strawberry. Seven lines of transgenic plants were preliminarily identified by PCR and β-glucurondiase (GUS) histochemical staining.