A STUDY OF THE EFFECTS OF TEMPERATURE AND OTHER FACTORS UPON THE GERMINATION OF VEGETABLE CROPS.: IV. ROOT CROPS

Abstract

Seeds of three varieties of each of three root crops (table beets, carrots, and rutabagas) and one bulb crop (onions) were placed in rolled-towel seed testers and subjected to controlled temperatures (35°, 40°, 45°, and 50°F.) for periods up to 22 days, and then transferred to a warm room for completion of germination. Significant differences in germination between varieties were noted for each crop. Table beets and onions were not appreciably affected by temperature treatment, but carrot germination was significantly reduced by temperatures below 50°F., and rutabaga germination was similarly reduced at 35°F. Only table beet germination was significantly altered by duration of exposure where germination increased after 8 and 15 days. There was a fairly well defined pattern in the effects of the interaction between temperature and duration of exposure. In most instances, maximum germination was obtained after 15 days’ exposure and minimum germination was associated with 1 or 8 days’ exposure, within a temperature treatment. Varietal interactions with temperature and duration of exposure indicated that genetical constitution may not be as important a factor in germination as suggested by other workers.