Effects of 2-Chloroethanephosphonic acid on Flower Types and Flowering Sequences in Muskmelon1

Abstract

Abstract Four concentrations of 2-chloroethanephosphonic acid (Ethrel) were applied at three stages of growth to andromonoecious, monoecious, and hermaphrodite muskmelon cultivars. Generally, Ethrel promoted female flower production and suppressed male flower initiation. Preflowering sprays, however, resulted in the production of exceptional pistillate flowers in andromonoecious and hermaphroditic cultivars, and hermaphroditic flowers in the monoecious cultivar. Appearance of the exceptional flowers generally followed, in all treated cultivars, a common pattern commencing with pistillate flowers and followed by increased frequency of hermaphrodite and male flowers. Exceptional flowers were fertile and capable of producing fruits with normal seed yield. Even though pistillate flowers developed at lower nodes on Ethrel-treated plants than on untreated plants, flower initiation was delayed, resulting in later maturity in all cultivars. Fruits on the treated plants were usually deformed, but seed yield and viability were normal.