John T.A. Proctor, Jong Chul Lee, and Sung-Sik Lee
Jong Chul Lee, Bernadine C. Strik, and John T.A. Proctor
American ginseng (Panax quinquefolium L.) roots have a dormancy period which can be satisfied by exposure to low temperatures of 0° to 10°C for about 100 days. Three-year-old roots of ginseng were weighed, given variable periods (≥ 50 days) of low temperature (5°C), planted in vermiculite in pots, and grown in light or dark at 5°, 10°, 15°, or 20°. After 50 to 100 days of storage at 5°, stem growth occurred at all temperatures except 20°. At this temperature, a minimum of 75 days at 5° was required to satisfy dormancy. Stem growth rate was relatively constant at 5° and 10° but increased with storage time when grown at 15° or 20°; leaf growth rate was affected similarly, except that no leaf growth occurred at 5°. If optimum cold storage and growth requirements were not met, the plants appeared abnormal and had reduced root dry weights. After 100 days of storage, the greatest growth rate was observed at 15° and 10°. Plant growth rate was the least at 5° and 20°.