ABSTRACT
The objective of this study was to develop a test to determine metabolic and imbibitional cold tolerance of cotton (Gossypium hirsutum L.) seed genotypes. Metabolic cold tolerance was determined by planting cotton seed in a sand media, exposing the seed to a constant temperature of 18OC for 21 days, and then counting and adjusting emergence percent for viable seed by dividing the emergence by the warm germination percent. Imbibiitonal cold tolerance was determined by chilling the seed in rolled foam pads at 5OC for six hours, planting the seed in a sand media, exposing the seed to a constant temperature of 30OC for 14 days, and then counting and adjusting emergence for viable seed by dividing emergence by warm germination percent. Varieties whose imbibitional and metabolic emergence percents were both above 80% ranked as having excellent cold tolerance. If both emergence percents were from 70% - 80%, the variety ranked as having good cold tolerance. Varieties that had both imbibitional and metabolic emergence percents between 50% and 70% had fair cold tolerance, and if either emergence percent was below 50%, the variety had poor cold tolerance.
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