Article

Ethylene Accumulation in Flooded Plants

Ohio Agricultural Research and Development Center, Wooster, Ohio, 44691, U.S.A.
Physiologia Plantarum (Impact Factor: 3.66). 04/2006; 36(3):236 - 241. DOI: 10.1111/j.1399-3054.1976.tb04420.x

ABSTRACT Ethylene concentration in sunflower (Helianthus annuus L.) cuttings increased 5-fold within 6 h after submersion in distilled water and then declined. When only the basal half of the cutting was steeped in water, ethylene concentration was slightly over half the concentration of the completely submerged cutting. Ethylene concentration also increased when cuttings were wrapped with moist paper tissue. When wrapped with Saran transparent plastic film, ethylene concentration increased continuously for 12 h. When part of the stem of an intact plant was wrapped with Saran, ethylene also increased in that part of the stem. When wrapping was removed or submersion was discontinued, accumulated ethylene in the cuttings decreased, much faster from unwrapped cuttings than from previously submerged ones. During 3 h submersion, ethylene production rate in submerged cuttings was approximately 10% of that for the controls and over 97% ethylene escaped out of the control cuttings while only 22-52% escaped from the submerged cuttings.Water content increased during submersion and decreased when submersion was discontinued. Water content did not change significantly during wrapping, but decreased when the cuttings were unwrapped. High water content in the submerged cuttings was apparently not related to the high ethylene concentration in the cuttings.Causes of ethylene increase in flooded plants were discussed and it was concluded that one of the first and major causes is the accumulation of ethylene in flooded portions of the plants due to the blockade of ethylene escape by water.

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