Ethephon Foliar Sprays Are Influenced by Carrier Water Alkalinity and Ambient Air Temperature at Application

in HortScience

The plant growth regulator (PGR) ethephon [(2-chloroethyl) phosphonic acid; ETH] can be sprayed on floriculture crops to inhibit internode elongation, hinder apical dominance, increase lateral branching, and abort flower buds and flowers. However, the efficacy of ETH can be reduced as the pH of the carrier water used to mix the spray solution or temperature increase. Therefore, our objective was to quantify how the efficacy of ethephon sprays is influenced by carrier water alkalinity (CaCO3; ALK) and the air temperature at application (TEMP). Young plants of verbena (Verbena peruviana) ‘Aztec Blue Velvet’, ivy geranium (Pelargonium ×peltatum) ‘Precision Pink’, and petunia (Petunia ×hybrida) ‘Easy Wave Neon Rose’ were transplanted into 11-cm-diameter containers and grown in a greenhouse with an average daily air temperature (ADT) set point of 21 °C. Before the ETH spray application(s), the ADT in each greenhouse compartment was changed from a set point of 21 °C to 14, 17, 20, 23, or 26 °C for ≈24 hours. Plants were sprayed with 0, 250, 500, or 750 mg·L−1 ETH mixed with carrier water containing ≈50, 150, or 300 mg·L−1 CaCO3 2 and 3 weeks (Expt. 1) or 1 or 2 weeks (Expt. 2) after transplant. Generally, high ALK had a negative effect on spray efficacy. For example, an increase in ALK from 50 to 300 mg·L−1 CaCO3 resulted in one and five fewer ivy geranium and verbena branches, respectively. In addition, as application TEMP increased above 23 °C, chemical efficacy generally decreased in all species. For instance, as ETH increased from 0 to 750 mg·L−1 across ALKs, inflorescence number of ivy geraniums increased from 7 to 18 at a TEMP of 23 °C, but was unaffected at 26 °C. Based on our results, we can conclude that both ALK and TEMP influence ETH efficacy and are additional factors for greenhouse growers to consider when making applications.

Contributor Notes

This work was supported by the U.S. Department of Agriculture National Institute of Food and Agriculture, Hatch project MICL02472.

We gratefully acknowledge support by the U.S. Department of Agriculture–Agricultural Research Service Floriculture and Nursery Research Initiative, Fine Americas, Inc., The Western Michigan Greenhouse Association, and the Metro Detroit Flower Growers Association for funding; Ball Horticultural Co. for plant material; The Blackmore Company for fertilizer; and Nathan DuRussel for technical assistance.

The use of trade names in this publication does not imply endorsement by Michigan State University of products named nor criticism of similar ones not mentioned.

Corresponding author. E-mail: rglopez@msu.edu.

Article Sections

Article Figures

  • View in gallery

    Time to flower for petunia, verbena, and ivy geranium sprayed with 0, 250, 500, or 750 mg·L‒1 ethephon concentrations (ETH), with carrier water alkalinities of 50, 150, or 300 mg·L‒1 CaCO3, and target average daily air temperatures at application of 14, 17, 20, 23, or 26 °C in Expt. 1. Each bar represents a mean of six plants, and error bars represent se.

  • View in gallery

    Increase in branch number and stem length from application to first open flower for verbena and ivy geranium and increase in stem length from application to first open flower for petunia sprayed with 0, 250, 500, or 750 mg·L‒1 ethephon concentrations (ETH), with carrier water alkalinities (ALKs) of 50, 150, or 300 mg·L‒1, and target average daily temperatures at application (TEMPs) of 14, 17, 20, 23, or 26 °C in Expt. 1. Letters indicate mean separation across TEMPs, ALKs, and ETHs by Student’s t test at P ≤ 0.05 within a species. Each bar represents a mean of six plants, and error bars represent se.

  • View in gallery

    Time to flower for petunia, verbena, and ivy geranium and inflorescence number at first open flower of ivy geranium sprayed with 0, 250, 500, or 750 mg·L‒1 ethephon concentrations (ETH), with carrier water alkalinities (ALKs) of 50, 150, or 300 mg·L‒1 CaCO3, and target average daily air temperatures at application (TEMPs) of 14, 17, 20, 23, or 26 °C in Expt. 2. Letters indicate mean separation across TEMPs, ALKs, and ETHs by Student’s t test at P ≤ 0.05 within a species. Each bar represents a mean of six plants, and error bars represent se.

  • View in gallery

    Increase in branch number and stem length from application to first open flower for petunia, verbena, and ivy geranium sprayed with 0, 250, 500, or 750 mg·L‒1 ethephon concentrations, with carrier water alkalinities of 50, 150, or 300 mg·L‒1 CaCO3, and target average daily temperatures at application of 14, 17, 20, 23, or 26 °C in Expt. 2. Each bar represents a mean of six plants, and error bars represent se.

Article References

  • AndersenA.S.1976Regulation of apical dominance by ethephon, irradiance and CO2Physiol. Plant.374303308

  • BaskinT.I.2005Anisotropic expansion of the plant cell wallAnnu. Rev. Cell Dev. Biol.21203222

  • BeaudryR.M.KaysS.J.1987Effects of physical and environmental factors on the release kinetics of ethylene from (2-chloroethyl)phosponic acid and (2-chloroethyl)-methylbis(phenylmethoxy)salineJ. Amer. Soc. Hort. Sci.114352359

    • Search Google Scholar
    • Export Citation
  • BeaudryR.M.KaysS.J.1988Flux of ethylene from leaves treated with a polar or non-polar ethylene-releasing compoundJ. Amer. Soc. Hort. Sci.113784789

    • Search Google Scholar
    • Export Citation
  • BiddleE.KerfootD.G.KhoY.H.RussellK.E.1976Kinetic studies of the thermal decomposition of 2-chloroethylphosphonic acid in aqueous solutionPlant Physiol.585700702

    • Search Google Scholar
    • Export Citation
  • BiernbaumJ.1994Water quality p. 65‒76. In: H.K. Tayama T.J. Roll and M.L Gatson (eds.). Tips on growing bedding plants. 3rd ed. O.F.A. Serv. Inc Columbus OH

  • BlanchardM.G.RunkleE.S.2007Dipping bedding plant liners in paclobutrazol or uniconazole inhibits subsequent stem extensionHortTechnology17178182

    • Search Google Scholar
    • Export Citation
  • BleeckerA.B.KendeH.2000Ethylene: A gaseous signal molecule in plantsAnnu. Rev. Cell Dev. Biol.161118

  • BriggsJ.C.FickeJ.F.1977Quality of rivers of the United States 1975 water year; based on the National Stream Quality Accounting Network (NASQAN) (No. 78-200). U.S. Geological Survey Reston VA

  • CamberatoD.M.CamberatoJ.J.LopezR.G.2014Determining the effect of carrier water pH and bicarbonate concentration on final pH of plant growth regulator solutionsHortScience4911761182

    • Search Google Scholar
    • Export Citation
  • ChahalG.RoskampJ.LegleiterT.JohnsonB.2012The influence of spray water quality on herbicide efficacy. <https://ag.purdue.edu/btny/weedscience/documents/Water_Quality.pdf>

  • CloydR.A.2007Effects of pH on insecticides and miticides p. 9‒11. In: R.A. Cloyd. Plant protection: Managing greenhouse insect and mite pests. Ball Publishing Batavia IL

  • CurreyC.J.WaltersK.J.McCabeK.G.2016aQuantifying growth control of lantana cultivars varying in vigor with ancymidol, flurprimidol, paclobutrazol, and uniconazole substrate drenchesHortTechnology26320326

    • Search Google Scholar
    • Export Citation
  • CurreyC.J.McCabeK.G.WaltersK.J.2016bConcentration and timing of ethephon drench applications interact to affect growth and flowering of containerized angelonia and geraniumHortScience5115421546

    • Search Google Scholar
    • Export Citation
  • DeSimoneL.A.McMahonP.B.RosenM.R.2015The quality of our nation's waters: Water quality in principal aquifers of the United States 1991-2010 (No. 1360). U.S. Geological Survey Reston VA

  • FeldmanL.J.1984Regulation of root developmentAnnu. Rev. Plant Physiol.351223242

  • FurukawaK.YangY.Y.HondaI.YanagisawaT.SakuraiA.TakahashiN.KamiyaY.1997Effects of ethylene and gibberellins on the elongation of rice seedlings (Oryza sativa L.)Biosci. Biotechnol. Biochem.615864869

    • Search Google Scholar
    • Export Citation
  • GanieZ.A.JugulamM.JhalaA.J.2017Temperature influences efficacy, absorption, and translocation of 2, 4-D or glyphosate in glyphosate-resistant and glyphosate-susceptible common ragweed (Ambrosia artemisiifolia) and giant ragweed (Ambrosia trifida)Weed Sci.655588602

    • Search Google Scholar
    • Export Citation
  • GodarA.S.VaranasiV.K.NakkaS.PrasadP.V.ThompsonC.R.MithilaJ.2015Physiological and molecular mechanisms of differential sensitivity of Palmer amaranth (Amaranthus palmeri) to mesotrione at varying growth temperaturesPLoS One105e0126731

    • Search Google Scholar
    • Export Citation
  • HammerA.2001Calculations. In: M.L. Gaston P.S. Konjoian L.A. Kunkle and M.F. Wilt (eds.). Tips on regulating growth of floriculture crops. O.F.A. Serv. Inc. Columbus OH

  • HayashiT.HeinsR.D.CameronA.C.CarlsonW.H.2001Ethephon influences flowering, height, and branching of several herbaceous perennialsScientia Hort.913‒4305324

    • Search Google Scholar
    • Export Citation
  • KaczperskiM.P.CarlsonW.H.KarlssonM.G.1991Growth and development of Petunia ×hybrids as a function of temperature and irradianceJ. Amer. Soc. Hort. Sci.1162232237

    • Search Google Scholar
    • Export Citation
  • KleinI.LaveeS.Ben-TalY.1979Effect of water vapor pressure on the thermal decomposition of 2-chloroethylphosphonic acidPlant Physiol.633474477

    • Search Google Scholar
    • Export Citation
  • LongstaffB.C.1988A modelling study of the effects of temperature manipulation upon the control of Sitophilus oryzae (Coleoptera: Curculionidae) by insecticideJ. Appl. Ecol.25163175

    • Search Google Scholar
    • Export Citation
  • LougheedE.C.FranklinE.W.1972Effects of temperature on ethylene evolution from ethephonCan. J. Plant Sci.525769773

  • McReynoldsR.D.KossuthS.V.1985CEPA in liquid sulfuric acid increases oleoresin yieldsSouth. J. Appl. For.93170173

  • McWhorterC.G.JordanT.N.WillsG.D.1980Translocation of 14 C-glyphosate in soybeans (Glycine max) and johnsongrass (Sorghum halepense)Weed Sci.281113118

    • Search Google Scholar
    • Export Citation
  • MillerW.B.MattsonN.S.XieX.XuD.CurreyC.J.ClemensK.L.LopezR.G.OlrichM.RunkleE.S.2012Ethephon substrate drenches inhibit stem extension of floriculture cropsHortScience4713121319

    • Search Google Scholar
    • Export Citation
  • MoccaldiL.RunkleE.S.2007Modeling the effects of temperature and photosynthetic daily light integral on growth and flowering of Salvia splendens and Tagetes patulaJ. Amer. Hort. Sci.132283288

    • Search Google Scholar
    • Export Citation
  • MuellerT.C.MainC.L.ThompsonM.A.SteckelL.E.2006Comparison of glyphosate salts (isopropylamine, diammonium, and potassium) and calcium and magnesium concentrations on the control of various weedsWeed Technol.20164171

    • Search Google Scholar
    • Export Citation
  • MusgraveA.JacksonM.B.LingE.1972Callitriche stem elongation is controlled by ethylene and gibberellinNat. New Biol.238819396

  • MusgraveA.WaltersJ.1973Ethylene-stimulated growth and auxin ansport in Ranunculus sceleratus petiolesNew Phytol.724783789

  • NalewajaJ.D.MatysiakR.1993Spray carrier salts affect herbicide toxicity to kochia (Kochia scoparia)Weed Technol.7154158

  • RademacherW.2000Growth retardants: Effects on gibberellin biosynthesis and other metabolic pathwaysAnnu. Rev. Plant Biol.511501531

  • RidgeI.OsborneD.J.1969Cell growth and cellulases: Regulation by ethylene and indole-3-acetic acid in shoots of Pisum sativumNature2235203318319

    • Search Google Scholar
    • Export Citation
  • RidgeI.1973The control of cell shape and rate of cell expansion by ethylene: Effects on microfibril orientation and cell wall extensibility in etiolated peasActa Bot. Neerl.222144158

    • Search Google Scholar
    • Export Citation
  • RobertsJ.A.SchindlerC.B.TuckerG.A.1984Ethylene-promoted tomato flower abscission and the possible involvement of an inhibitorPlanta1602159163

    • Search Google Scholar
    • Export Citation
  • USDA2016National Agricultural Statistics Service. Floriculture crops 2015 summary. 20 June 2018. <http://usda.mannlib.cornell.edu/usda/current/FlorCrop/FlorCrop-04-26-2016.pdf>

  • VoesenekL.A.C.J.BlomC.W.P.M.1989Growth responses of Rumex species in relation to submergence and ethylenePlant Cell Environ.124433439

  • WarnerH.L.LeopoldA.C.1969Ethylene evolution from 2-chloroethylphosphonic acidPlant Physiol.441156158

Article Information

Google Scholar

Related Content

Article Metrics

All Time Past Year Past 30 Days
Abstract Views 197 197 55
Full Text Views 54 54 0
PDF Downloads 18 18 1