Helianthus annuus Transcriptome or Gene expression. Helianthus annuus

Abiotic stress and more specifically drought is the major limiting factor for sunflower production. ABA is a key hormone for drought stress response in plants and sunflower. This experiment aims at identifying ABA responsive pathways in order to better understand sunflower responses to drought. We studied in parallel microRNA profiles on the same samples and we will try to identify sunflower microRNA regulated genes in response to ABA. The ultimate goal will be improve sunflower breeding through selection of key drought response genes.-The experiment consisted of 3 repeats of four 12-day-old-plantlets of sunflower genotype SF193 (INRA code: XRQ) grown in growth chamber conditions and submitted to a 6-hour-treatment of 10 µM absissic acid or not. Growth conditions were 14h light at 23°C and 10h night at 20°C under fluorescent bulbs. Plants were grown in 6 hydroponic boxes containing 20 litres of aerated liquid culture medium (as described in Massonneau et al., 2001 Planta). Leaves (not cotyledons) 1 to 4 were harvested 4 hours after light onset and frozen immediately in liquid nitrogen. Overall design: 6 arrays - SUNFLOWER; treated vs untreated comparison