Cotton plants (Gossypium hirsutum cv. Stoneville 213), were grown in an environmental growth room as previously described (4), and at 5 weeks of age, they were treated with aqueous solutions containing 0, 25, 50, 100, or 200 mg/liter of AgNO3 plus 0.01 % Tween 20 as a surfactant. The following day, treated and control plants were placed in two large chambers (4). One chamber was purged with 12 Al/liter of ethylene at 18 liters/min, while the other was purged with air at the same flow rate.