Transcriptome Profiling of Potato
The potato (Solanum tuberosum L.) strain Ningshu 4 was from our own lab. All plant materials were collected from our Guyuan Experimental Field (Guyuan, Ningxia Hui Autonomous Region, China), which does not involve any endangered or protected species. Before squaring stage, 40 healthy and uniform ball-plants were transplanted into buckets and cultivated indoors at room temperature under 12-hr light/dark cycles at 4,000 lux. Experimental soil was collected from a test site in Guyuan City, Ningxia Hui Autonomous Region, with the maximum field water-holding capacity of 15%.  At flowering stage, the above plants were split in to three groups with ten plants in each group. The first group of plants was exposed to severe drought stress treatment (DT) for three days, during which relative soil moisture was controlled at 35–40% of the maximum field water-holding capacity. The second group of plants was exposed to severe drought stress treatment for 3 days, followed by re-watering to the control level and grown for 3 days (RWT). And the last group of plants was maintained under normal watering condition throughout the time period as control (CT). Then, stolon tips from three randomly selected plants of each group were pooled together, immediately grounded into fine powder in liquid nitrogen for sequencing analysis.