Greenhouse study
Seeds from wild type Coker 312, AtHSP101 transgenic and null-transgenic lines were planted into 30 cm diameter pots containing Sunshine Mix #1 soil (Sun Gro Horticulture Distributors Inc., Bellevue, WA), 3 seeds per pot. Seedlings were thinned one week following planting to one plant per pot. For temperature treatment, five pots per line were placed on benches in greenhouses set to provide either 31/27°C or 43C/28°C day/night temperatures with a 16h/8h photoperiod. All other growth conditions such as light and nutrient levels were maintained the same for both greenhouses. The pots in each greenhouse were grouped as one pot per line and placed on different benches in the greenhouse. After entering reproductive stages, flowers were harvested at the day of opening for pollen germination study. Thirty-five days after first flowering, cotton bolls were harvested. Number of bolls per plant, number of seeds per plant and other yield related parameters were recorded.