Sodininkystė ir daržininkystė - Sodininkystės ir daržininkystės institutas

generated using ozone generator OSR-8 (Ozone Solutions, Inc., Sioux Center,USA) and the concentrations were measured using Portable Ozone MonitorOMC-1108 (Ozone solutions, Inc., Sioux Center, USA). Photoperiod of 16 hand day/night temperature of 21/17°C was maintained throughout theexperiment. High-pressure sodium lamps SON-T Agro (PHILIPS,Massachusetts, USA) were used for illumination. Plants were watered whennecessary. Experiment was carried out in three replications. Radish was keptfor 14 days in phytotron chambers after ozone fumigation in order to studyregeneration of radish organs and changes in physiological measurements.Samples for high-performance liquid chromatography (HPLC) wereprepared by grounding 1 to 2 g of fresh tissue per sample into powder underliquid nitrogen treatment. The extracts were centrifuged and pre-purified usingsolid-phase extraction with NH 2- cartridge columns. The prepared sampleswere stored in vials at 4°C, as proposed by Wang et al. (2003).Analysis of gibberellic acid (GA 3), indolyl-3-acetic acid (IAA), abscisicacid (ABA) and zeatin was performed using HP 1050 Series liquidchromatography system with variable wavelength UV-VIS detector (AgilentTechnologies, Waldbronn, Germany). Intersil ODS-2 column (150 x 4.6 mm 2 )(Alltech, Deerfield, USA) was used for phytohormones separation. Mobilephase: 45% methanol containing 1% acetic acid. Flow rate: 1 mL/min. Thewavelengths of 254 nm for GA 3and ABA detection, 270 nm for zeatin and280 nm for IAA detection were set.Data analysis was performed using MS Excel and OriginPro 7.0 software.Phytohormone ratio was calculated taking in account, that IAA concentrationis equal to 1. Data errors presented in Fig. 1 and 2 are the standard deviationsof analytical measurements of identified phytohormones.The following chemicals were used: isopropanol (POCH, Poland),imidazole, GA 3, IAA, ABA and zeatin (Sigma-Aldrich, Germany), NH 2–cartridges (Supelco, USA), methanol and hexane (LaChema, Czech Republic),acetic acid (BOH, England).Results. The results of phytohormone analysis after 7 days of exposure ofdifferent ozone concentrations are presented in Fig. 1. The gibberellic acid(GA 3) content was higher under treatment with 80 and 160 µg m -3 ozoneconcentrations, though significant decrease was observed in the 240 µg m -3treatment, comparing to control. Zeatin quantity, contrarily, decreased withincreasing O 3concentration and considerably increased at the highest ozonetreatment. Indolyl-3-acetic acid (IAA) contents gradually declined at higherozone concentrations. ABA contents were distributed unequally in alltreatments: it was higher (0.23 µg m -1 ) at 80 µg m -3 ozone concentration,compared to control, lower (0.15 µg m -1 ) at 160 µg m -3 and the same as thecontrol (0.20 µg m -1 ) in 240 µg m -3 variant. Evaluating phytohormone ratio,taking in account, that IAA=1, the lowest zeatin/IAA and the highestGA 3/IAA ratio was in the 160 µg m -3 treatment.172