In vitro protein synthesis with polysomes from unpollinated, cross- and self-pollinated Petunia ovaries.

From in-vitro protein synthesis studies it has been shown that in Petunia hybrida (clone W166K, incompatibility genes S1S2) the ovary is stimulated to synthesize proteins before the pollentubes reach the ovary. A difference in protein metabolism is detected after self- and cross-pollination. On the basis of this result has been concluded that a signal has to be sent from the stigma or the style towards the ovary which induces the changes in metabolic activity. The signal must be different for cross- and self-pollination.