Ethylene Affects Postproduction Quality of Easter Cactus

Abstract

Experiments were performed to determine the effects of ethylene (C2H4) on the postproduction quality of Easter cactus [Hatiora gaertneri (Reg.) Barthlott and H. ×graeseri (Werderm.) Barthlott]. Significant differences in percent bud abscission were observed among cultivars when plants were exposed to 0.4 or 1.0 μL·L-1 C2H4 for 48 hours. Fewer buds abscised on `Andre' and `Red Pride' than on `Evita', `Rood', and `Thor-Anne'. Stage of floral development at the time of C2H4 exposure affected the pattern and severity of bud abscission for `Crimson Giant'. Percent bud abscission was greater for plants treated with 0.5 μL·L-1 C2H4 in the small-bud stage (largest buds 7 to 13 days from anthesis) than for plants treated in the medium-bud stage (largest buds 3 to 4 days from anthesis) or large-bud stage (largest buds 1 day from anthesis). Application of 1 or 2 mm silver thiosulfate (STS) was as effective as 3 mm STS in reducing bud abscission on plants exposed to 0.5 μL·L-1 C2H4 in the small-bud stage. Treatment with 2 mm STS before C2H4 exposure increased the display life (number of days from anthesis of the first flower to senescence of the last flower) of `Andre' in all three developmental stages, but increased the display life of `Crimson Giant' only in the small bud stage. These results demonstrate that the response of Easter cactus to C2H4 is affected by cultivar, C2H4 concentration, stage of floral development at the time of C2H4 exposure, and STS pretreatment.