Routes of Ethephon Uptake in Pineapple (Ananas comosus) and Reasons for Failure of Flower Induction

Abstract

Ethylene-releasing agents such as ethephon (2-chloroethylphosphonic acid) are used widely to induce flowering in pineapples (Ananas comosus (L.) Merrill). However, ethephon treatment is less reliable in summer, particularly if plants are treated on abnormally hot days. [(14)C]ethephon was used to follow uptake and translocation in leaf tissues. Up to 30% of the ethephon entered the leaf within 4 h, and up to 60% by 24 h. Uptake was dramatically modified by temperature, relative humidity, solution pH, and the surface on which solution droplets were placed. Entry occurred across the leaf cuticle and probably also by way of stomatal pores, and label was recovered at all depths within the leaf. (14)C label entered more rapidly through the abaxial epidermis than through the adaxial epidermis. Low-volume spray applications to whole plants resulted in rapidly drying droplets mainly on the adaxial, distal epidermis and were rather ineffective at inducing flowering, possibly because little ethephon or ethylene reaches the shoot apex. High-volume sprays may facilitate ethephon entry because solution accumulates in leaf axils and hence remains in prolonged contact with abaxial epidermis of leaf bases close to the shoot apex. When poured into the center of the plant, 20% of a normal commercial ethephon dose induced full flowering even under adverse temperatures. It is suggested that high-volume evening spraying and avoidance of hot days may reduce the incidence of flowering failure.

Physiological changes associated with senescence and abscission in mature citrus fruit induced by 5‐chloro‐3‐methyl‐4‐nitro‐1H‐pyrazole and ethephon application

“…Recent work demonstrated the uncoupling effect of CMNP, and a link between cellular energy shortage, lipid signaling and citrus abscission was suggested (Alferez et al 2005). Ethephon is an agrochemical used to advance ethylene-related processes such as abscission in cherries and flowering in pineapple (Bukovac et al 1969, Turnbull et al 1999. Ethephon uptake into plant tissue results in cleavage of the molecule to yield ethylene, but hydrochloric acid and phosphate are also released (Warner and Leopold 1969).…”

Effect of 1-MCP on Cotton Plants under Abiotic Stress Caused by Ethephon

“…In weed seed germination studies only a small portion of 14 Clabeled ethephon was released as ethylene [45]. Others have also shown low and inconsistent ethephon conversion efficiency [46] [49]. Thus, the application of ethephon may not always mimic ethylene treatment.…”

“…Plants need oxygen for respiration and energy release. CO 2 fixation is limited by environmental stresses, such as cold and high temperature, drought, and salt stress which reduce NADP + regeneration and thus induce accumulation of ROS including hydrogen peroxide (H 2 O 2 ), superoxide radical (O 2− ), and hydroxyl radicals (OH − ) in leaves [45] [46]. Previous cotton research showed that premature leaf senescence, reflected as aggregated membrane damage, lipid peroxidation, and decreased photosynthesis, is a result of imbalance of ROS metabolism.…”

Effect of Ca²⁺ Regulators on the CaM Gene Expression in <i>Guzmania</i> ‘Amaranth’ during Flower Induction by Ethylene

“…In order to appear on the market on time, flowering-inducing agents, such as ethylene and its analogue, were used for the cultivation of bromeliads. The rosulated leaf of bromeliads can filtrate the water and nutrition, and the scalelike hairs on the leaf base epidermis can absorb water, nutrition and ethylene (Turnbull et al, 1999). Exogenous ethylene and its analogue might induce bromeliads flower by increasing endogenous ethylene.…”