Influence of growth temperature on vegetative tissues in tomato

In this study, plants of tomato Solanum lycopersicum cultivar LA4024 were grown on soil in phytocabinets (CLF Plant Climatics, Emersacker, Germany; model AR-66-L) under long-day (16h light, 8 h darkness) conditions. In control conditions (CN), the daytime temperature was 23C and in heat stress conditions (HS) it was 32C or 37C respectively. In both conditions the temperature at night was set to 23C, the relative humidity was 65 % and the light intensity between 150 and 200 pmol s-1 m2. The sampling was done by immediately freezing the plant material in liquid nitrogen. After the material was grinded in a mortar the material was stored at -80C until further processing.Total RNA was extracted from young cotyledons, mature cotyledons, apex tissue, young leaves, and mature leaves using the RNeasy Plant Mini Kit (Qiagen United States) following the manufacturer's protocol. For each sample, one microgram of total RNA was treated with DNA-freeTM DNA Removal Kit (AM1906, Invitrogen) and cDNA was synthesized using the Proto-Script first strand cDNA synthesis kit (New England Biolabs). It was then Illumina sequenced with 150 bp paired-end sequencing.