Rajasekaran, L. R., Stiles, A. and Caldwell, C. D. 2002. Stand establishment in processing carrots - Effects of various temperature regimes on germination and the role of salicylates in promoting germination at low temperatures. Can J. Plant Sci. 82: 443-450. The effects of various temperature regimes on carrot seed germination and the possibility of hastening germination at a low temperature using salicylates were studied. Seeds were incubated at various temperatures viz., 25, 20, 15, 10, 5 and 2degreesC. Salicylates such as, 2,6-dihydoxybenzoic acid (DHBA), acetylsalicylic acid (ASA), salicylic acid (SA) were supplied at 0, 1, 10, 100 and 1000 in,- L-1 continually to the seeds incubated at 25 and 5degreesC until germination. Data on germination percentage were collected, and vigor value was calculated. Incubating seeds at various low temperature regimes significantly and proportionately reduced germination percentage and vigor value. The highest cumulative germination and vigor value was obs erved at 25degreesC. Critical threshold temperature for germination (GT(50)) was 5degreesC. Seed treatment using salicylates hastened germination at 5degreesC. 2,6-dihydoxybenzoic acid 1, ASA 100 and SA 1 mg L-1 all were effective in hastening germination at 5degreesC. Among all the salicylates, ASA 100 mg L-1 was the most effective in advancing germination at 5degreesC. Salicylates at the highest concentration of 1000 mg: L-1 inhibited germination significantly both at 25 and 5degreesC.
