Correlation of spermine levels with ovary senescence and with fruit set and development inPisum sativum L.

Separation and quantitation of polyamines from unpollinated pea (Pisum sativum L.) ovaries and young fruits induced by application of gibberellic acid to unpollinated ovaries showed, in both cases, a decrease in putrescine and spermidine levels between anthesis and 4 d later. By contrast, spermine levels increased prior to the onset of senescence of the unpollinated ovaries (3 d post anthesis) and decreased during fruit development. Low levels of putrescine, spermidine and spermine were also observed in young fruits obtained by self-pollination and by treatment of unpollinated ovaries with 2,4-dichlorophenoxyacetic acid. In-vitro culture of ovary explants in a medium containing spermine showed that a reduction of the growth of gibberellic acid-treated unpollinated ovaries was associated with a rise in the level of spermine in the fruits. The results obtained indicate that changes in spermine levels are involved in the control of ovary senescence and of fruit set and development.