Transcriptome data of lettuce under LED periodic dark-pulse light condition in closed-type plant factory

Experiments were carried out using lettuce (Lactuca sativa L cv. Frill ice, Snow Brand Seed Co. Ltd., Hokkaido, Japan) cultivated in a closed-type plant factory. Seeds were sown on a water-laden urethane sponge in a tray filled with water and incubated for a week under fluorescent light. After one week, seedlings were transplanted to the multistage hydroponic system. The light sources used were red, green and blue LEDs. Cultivation was performed using a Deep Flow Technique hydroponic system. We set four light conditions: constant light, 23.75h Light/0.25h Dark, 23.5h Light/0.5h Dark, 23h Light/1h Dark. We sampled aerial part 3d, 4d and 15d after transplanting. The aerial parts were immediately frozen in liquid nitrogen and stored at -80 degree. We prepared a RNA-Seq library and obtained the sequence read files using a HiSeq 2000 sequencer. 23.75h Light/0.25h Dark and 23.5h Light/0.5h Dark was set as asynchronous condition of the circadian clock. 23h Light/1h Dark was set as synchronous condition of the circadian clock.