Flower senescence in many plants is associated with a significant increase in ethylene production. This ethylene has been shown to play a regulatory role in the demise of the petals. The regulation of petal senescence by ethylene is thought to facilitate the ordered breakdown and remobilization of cellular constituents to other plant and flower organs. In order to gain insight in the remobilization of cellular constituents, we investigated changes in P, Ca, Mg, Mn, Cu, Fe, and Co concentrations in petunia corollas from flowers at anthesis through senescence. Our results showed that all elements in our study were present in lower concentrations in corollas than mature leaves. Phosphorus concentration decreased from ≈2000 mg·kg-1 in presenescent corollas to 1500 mg·kg-1 in senescing tissue, a change correlated to increases in ethylene production by the corollas. Increases in Ca, Mg, and Mn concentrations were noted during development of corollas from anthesis to senescence. However, no clear correlation exists between these changes and the ethylene climacteric since increases were gradual and continuous from anthesis to senescence. Calcium concentrations increased 3- to 4-fold from anthesis to senescence. Changes in Mg and Mn concentrations were less pronounced and were limited to 2- to 3-fold increases for Mn and a 2-fold increase for Mg. Concentrations of Cu, Fe, and Co fluctuated throughout development and ranged from 2 to 14, 88 to 544, and 0 to 4 mg·kg-1, respectively.
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