Effects of various chemical agents and early ethylene production on floral senescence of Hibiscus syriacus L.

Abstract

To understand the factors that induce floral senescence in Hibiscus syriacus L., we have investigated the effects of various chemical agents on flower senescence at two different flowering stages, before and after full bloom, as well as the relationship between flower longevity and endogenous ethylene production before full bloom. Treatments with ethylene, 1-aminocyclopropane-1-carboxylic acid (ACC), and ethephon enhanced floral senescence, while aminoethoxyvinylglycine (AVG) promoted flower longevity regardless of treatment timing. Although ethanol slightly extended flower longevity, abscisic acid (ABA), nitric oxide, boric acid and sucrose, which have been reported to affect flower longevity or senescence, had no effect on H. syriacus floral senescence. The polyamine spermine (SPM), methylglyoxal-bis(guanylhydrazone) (MGBG), an inhibitor of SPM biosynthesis, and cycloheximide (CHI) accelerated flower senescence when applied before full bloom, but had no effect when applied after full bloom. SPM, MGBG and CHI treatments resulted in enhanced ethylene production during flower opening, and the promotion of flower senescence is mediated by ethylene production prior to full bloom. Furthermore, endogenous ethylene, spontaneously produced before blooming, was closely associated with floral senescence. These results suggest that ethylene production during flower opening plays a key role in determining the timing of Hibiscus flower senescence.

Characteristics of cadmium uptake and membrane transport in roots of intact wheat (Triticum aestivum L.) seedlings

“…In other report, it was also found that accumulation of Cd after 24 h increased in yeast cells transformed with a PCS1 gene (phytochelatin synthase 1 gene) from wheat (Clemens et al, 1998). To further investigate whether the transport of Cd into the root of wheat takes place via specific transport proteins, the root was treated with a typical protein synthesis inhibitor CHX (Seo et al, 2009). Upon CHX treatment, the Cd 2þ uptake and influxes in the roots decreased significantly, indicating that specific transport proteins are involved in Cd 2þ uptake by wheat.…”

Etileno y retardantes de la maduración en la poscosecha de productos agrícolas. Una revisión

“…Los tratamientos precosecha y poscosecha con AVG disminuyen la producción de etileno, la respiración, el ablandamiento, la degradación de clorofilas, la pérdida de peso, en general retrasan el proceso de maduración en frutos climatéricos (Hayama et al, 2008) y flores de corte (Seo et al, 2009). Algunos estudios muestran que el AVG no afecta negativamente las características organolépticas de los frutos, sin embargo, puede alterar del desarrollo de aroma, debido a la disminución del contenido de volátiles (Salas et al, 2011;Romani et al, 1983).…”