*2.5. Expression Analysis of SlBAG Genes*

Seeds of *Solanum lycopersicum* cv. Ailsa Craig were sterilized and sown in the solid Murashige and Skoog (MS) medium at 25 ◦C/20 ◦C, and 20-day-old seedlings were used for the following treatments. For *SlBAG* gene expression under stresses, tomato seedlings were cultured in liquid MS medium for 24 h, then exposed to salt, drought, high temperature, cold, cadmium, H2O2, and ABA treatment for 1, 3, 6, 12, 24, and 48 h. Tomato plants were transferred to liquid medium containing 100 mM NaCl, 20% polyethylene glycol-6000, 50 uM cadmium, 100 uM ABA, and 10 mM H2O2, respectively.

For HT and cold, the seedlings were exposed to HT (42 ◦C) or 4 ◦C conditions. All real leaves were collected, frozen, and preserved at −70 ◦C for RNA extraction. For organsspecific expression of *SlBAG* genes, organs from root, stem, leaf, flower, green fruit, and red fruit of different stages were collected according to the method of Ding et al. [23]. The transcription levels of *SlBAG* genes were determined by quantitative real-time PCR (qRT-PCR).
