Effect of silver ion, carbon dioxide, and oxygen on ethylene action and metabolism

The relationship between ethylene action and metabolism was investigated in the etiolated pea seedling (Pisum sativum L. cv. Alaska) by inhibiting ethylene action with Ag⁺, high CO₂, and low O₂ and then determining if ethylene metabolism was inhibited in a similar manner. Ag⁺ (100 milligrams per liter) was clearly the most potent antiethylene treatment. Ag⁺ pretreatment inhibited the growth retarding action of 0.2 microliters per liter ethylene by 48% and it also inhibited the incorporation of 0.2 microliters per liter ¹⁴C₂H₄ into pea tips by the same amount. As the ethylene concentration was increased from 0.2 to 30 microliters per liter, the effectiveness of Ag⁺ in reducing ethylene action and metabolism declined in a similar fashion. Although Ag⁺ significantly inhibited the incorporation of ¹⁴C₂H₄ into tissue metabolites, the oxidation of ¹⁴C₂H₄ to ¹⁴CO₂ was unaffected in the same tissue.