*2.4. Plant Materials, Growth Conditions and Stress Treatments*

In the present study, two inbred eggplant lines (selected by the Vegetable Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China), the thermotolerant line 05-4 and the thermosensitive line 05-1, were used. Eggplant seedlings were cultivated under 25/20 ◦C day/night conditions and a 16/8 h day/night photoperiod in a growth chamber until the four true leaves period for treatments. For the HS treatment, the seedlings of 05-1 and 05-4 with four leaves were directly placed in the 42 ◦C light incubator (RXZ-1000B3, Jiangnan Instrument Factory, Ningbo, China). For the heat treatment used for RNA-seq, the 3rd mature leaves of treated seedlings were collected at 0 and 6 h after HS treatment and 10 plants were used for each treatment. For the heat treatment used for the qRT-PCR, the 3rd mature leaves from two different lines were harvested at 0 and 6 h. The samples were harvested, immediately frozen in liquid nitrogen and stored at −80 ◦C for RNA extraction. Three biological replicates were performed and each replicate had 10 plants.
