We all appreciate the fantastic diversity of flowers. How flowers diversified, however, remains largely enigmatic. The mechanisms underlying the diversification of flowers are complex because the overall appearance of a flower is determined by many factors, such as the shape and size of its receptacle, and the arrangement, number, type, shape and colour of floral organs. Modifications of the developmental trajectories of a flower and its components, therefore, can lead to the generation of new floral types. In this Review, by summarizing the recent progress in studying the initiation, identity determination, morphogenesis and maturation of floral organs, we present our current understanding of the mechanisms underlying the diversification of flowers.
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H.K. wishes to thank support from the Strategic Priority Research Program of the Chinese Academy of Sciences (grant no. XDB27010304), the National Natural Science Foundation of China grants (grant nos. 31330007 and 91631308), the CAS/SAFEA International Partnership Program for Creative Research Teams and the National Ten-Thousand Talents Program of China.
The authors declare no competing interests.
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