Floral Meristems


Meristems refer to a group of undifferentiated dividing cells that are responsible for the formation of plant organs. Floral meristems are a group of dividing cells that give rise to flowers. The formation of a floral meristem and its subsequent fate are under both environmental and molecular control. Several exogenous environmental factors and a complex network of genes control this process.

Keywords: ABC model; flowering time; meristem; patterning; organogenesis

Figure 1.

A simplified scheme summarizing the various genes and pathways involved in floral transition. For simplification several circuits have been omitted. Arrows indicate positive inputs and blocked lines represent inhibitory inputs and the lines do not necessarily indicate direct activation or repression.

Figure 2.

A scheme detailing the ABC model and the mutant phenotypes when corresponding functions are missing. To the left, a series of longitudinal sections representing half‐flowers are shown describing the phenotype of wild type and various mutants lacking the indicated function. At the top, the whorl numbers are indicated. To the right, a cartoon depicts an overview of the types of floral organs and their concentric arrangement. Ca, carpel; Pe, petal; Se, sepal; St, stamen and WT, wild type. Adapted from Weigel and Meyerowitz .



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Further Reading

Bowman JL (2000) The YABBY gene family and abaxial cell fate. Current Opinion in Plant Biology 3(1): 17–22.

Koornneef M, Alonso‐Blanco C, Peeters AJM and Soppe W (1998) Genetic control of flowering time in Arabidopsis. Annual Review of Plant Physiology and Plant Molecular Biology 49: 345–370.

Parcy F (2005) Flowering: a time for integration. International Journal of Developmental Biology 49(5–6): 585–593.

Quesada V, Dean C and Simpson G (2005) Regulated RNA processing in the control of Arabidopsis flowering. International Journal of Developmental Biology 49(5–6): 773–780.

Searle I and Coupland G (2004) Induction of flowering by seasonal changes in photoperiod. EMBO Journal 23(6): 1217–1222.

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How to Cite close
Schneitz, Kay, and Balasubramanian, Sureshkumar(Mar 2009) Floral Meristems. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1002/9780470015902.a0002053.pub3]