Effects of Ethephon Spray on Plant Quality and Growth Parameters of Potted Narcissus tazetta

Abstract

The effects of ethephon treatment applied as a foliar spray on plant height, flowering time, flower quality and growth parameters of native narcissus (Narcissus tazetta L.) grown in pots were investigated. When plants were 7-10 cm tall, ethephon at 0, 1000 and 2000 µL L-1 was applied as a foliar spray. The effects of ethephon treatment on plant height, leaf length, the time of flowering, number of flowers and the flower longevity were determined. In addition, the effects of ethephon spray on growth parameters, including leaf area ratio (LAR), specific leaf area (SLA), leaf thickness (LT), leaf weight ratio (LWR) and stem weight ratio (SWR) were examined and analysed in native narcissus. When narcissus grown in pots in the greenhouse reached the sale stage, plants were transferred to the laboratory at 20°C to evaluate their postproduction longevity and quality. The narcissus plants treated with 2000 µL L-1 ethephon were 41% (7.5 cm) shorter than untreated control plants (12.7 cm), while the treatment with 1000 µL L-1 ethephon shortened the plant height by 35% (8.3 cm). These effects of treatments on plant height were maintained under laboratory (home-office) conditions after production. Ethephon treatment significantly decreased the LAR and SLA values, but slightly not significantly increased the LT, LWR and SWR. Therefore, the ethephon treatment provides more compact and shorter plants with smaller LAR and SLA values. © 2019 International Society for Horticultural Science. All rights reserved.