Changes in abscisic acid and flower pigments during floral senescence of petunia

Abstract

The present work was focused on abscisic acid (ABA) changes in three differently coloured petunias during flower development and senescence. The ABA content was studied in correlation with changes of flower pigments and other phytohormones. The variations of anthocyanins and endogenous hormones were induced by treatments with 1 or 2 mM amino-oxyacetic acid (AOA), 50, 100 μM thidiazuron (TDZ) and 50 μM 6-benzyladenine (BA). ABA content decreased during bud development and increased during senescence. The AOA reduced the anthocyanins content and avoided ABA increase, while the cytokinins (BA and TDZ) did not significantly affected anthocyanin contents but increased ABA content. TDZ doubled the ABA content compared to the control. However, the treatments did not affected flower life, confirming the secondary role of ABA during flower senescence.

Influence of exogenously applied abscisic acid on carotenoid content and water uptake in flowers of the tea plant (Camellia sinensis)

“…During floral development the carotenoid concentration decreased. Petunia senescing petals also contain lower levels of carotenoids compared with flower buds . Not only the concentrations of carotenoids are subjected to changes, but also principal component analysis demonstrated that significant differences exist between the metabolic profiles of flowers of different developmental stages …”

“…Petunia senescing petals also contain lower levels of carotenoids compared with flower buds. 13 Table 2). that significant differences exist between the metabolic profiles of flowers of different developmental stages.…”

“…Carotenoids were identified by co‐chromatography with authentic reference material (neoxanthin, violaxanthin, lutein, zeaxanthin, α‐carotene and β‐carotene). The total carotenoid content of flowers harvested in 2009 (mg kg −1 fresh weight) was estimated spectrophotometrically …”

“…The total carotenoid content of flowers harvested in 2009 (mg kg −1 fresh weight) was estimated spectrophotometrically. 13 Extraction and analysis of ABA The extracts were prepared as described by Cho et al 14 Ten grams of tea flowers harvested in 2009 ground to a fine powder were extracted with 50 mL methanol overnight at 30 • C. Afterwards the plant residues were removed by filtration and the solvent by rotary evaporator. The residue was partitioned between 2% NaHCO 3 (m/v) and CH 2 Cl 2 (30 mL each).…”

Spatial and temporal transcriptome changes occurring during flower opening and senescence of the ephemeral hibiscus flower,Hibiscus rosa-sinensis

“…This is possible because many of these pigments, such as anthocyanins and carotenoids, are potent antioxidants and protect the cells from the damage caused by senescence. Higher anthocyanin content is associated with longer flower life in petunia (Ferrante et al , 2006). …”