Effect of low temperature on hybrids.

<p>(<b>A</b>) Rosettes of plants grown for four weeks at 16°C in long days and then transferred to 4°C in short days for 16 weeks. Size bar = 1 cm. (<b>B</b>) Seed set for plants that were exposed to a six-week period of 4°C (short days) one week after sowing, and afterwards returned to the indicated temperatures. Averages from at least 15 individuals are shown. Seed set was significantly different between F₁ and F₁ amiR-ACD6 plants at 16°C (p<0.001), but not at 23°C (p = 0.60).