Effect of Ethylene Upon Respiration of Lemons

Ethylene at concentrations of one part in one thousand of air, one part in ten thousand, one part in one hundred thousand, and one part in one million increased the respiration of green lemons. The effect appeared to be greatest at the intermediate concentrations, although more work to establish the concentration yielding the maximum effect is necessary. 2. The increase in carbon dioxide output ranged from about 100 per cent to about 250 per cent. 3. After the respiration of a given lot of lemons had been increased by the use of ethylene, a discontinuance of the ethylene applications led to a decrease. 4. Yellowing of the ethylene treated fruit became visible about the third or fourth day, and full yellow color was developed in six to ten days. Untreated fruit remained green during the same period of time.