Abstract: The change of the intra- and extra-cellular pH played important roles in plant growth and development and response to environmental stresses . Rapid alkalinization factors ( RALF) were polypeptide signals in the plant , belonging to a large gene family . The activity of RALF could induce extra-cellular pH increasing rapidly .Many studies on RALFs were in Solanum, including the structure and maturation , the gene expression , receptors and functions and so on. Combining our recent findings on the rdationship between RALF and fertility in plants, the present paper introduced the process of the research
on the RALF in Solanum and provided references for the further studies in this orea .

Key words: Rapid alkalization factor