THE USE OF ETHYLENE, PROPYLENE, AND SIMILAR COMPOUNDS IN BREAKING THE REST PERIOD OF TUBERS, BULBS, CUTTINGS, AND SEEDS

Abstract

The dormancy of potato tubers is longest in Early Ohio and shortest in Bliss Triumph and Burbank Russet. Ethylene at a concentration of 1:1000 parts of air by volume breaks the rest period and hastens the sprouting of tubers. The time gained by such a treatment varies from 7 days in the case of the Early Ohio variety to 8 or 9 days for Green Mountain and Rural, and 15 days for Burbank Russet and Bliss Triumph. The treated tubers grow faster than untreated ones. The growth stimulation by ethylene and by propylene is greater than the stimulation of ether and chloroform in gladiolus. Ethylene oxide, 1:1000 parts of water, was toxic to potato tubers and to gladiolus. Ethylene, either alone or after treatments by H2SO4, is effective in securing germination of seed of buckthorn, high bush cranberry, Tartarian honeysuckle, and snowberry. Ethylene and propylene were about equally effective in breaking dormancy.