title: Variation of microsporogenesis in monocots producing monosulcate pollen grains.
abstract: OBJECTIVE
  Microsporogenesis leading to monosulcate pollen grains has already been described for a wide range of monocot species. However, a detailed study of additional callose deposition after the completion of the cleavage walls has been neglected so far. The study of additional callose deposition in monosulcate pollen grain has gained importance since a correlation between additional callose deposition and aperture location has recently been revealed.
  
  
  METHODS
  Microsporogenesis is described for 30 species belonging to eight families of the monocots: Acoraceae, Amaryllidaceae, Alstroemeriaceae, Asparagaceae, Butomaceae, Commelinaceae, Liliaceae and Xanthorrhoeaceae.
  
  
  RESULTS
  Five different microsporogenesis pathways are associated with monosulcate pollen grain. They differ in the type of cytokinesis, tetrad shape, and the presence and shape of additional callose deposition. Four of them present additional callose deposition.
  
  
  CONCLUSIONS
  In all these different microsporogenesis pathways, aperture location seems to be linked to the last point of callose deposition.
authors.affiliation: Univ. Paris-Sud, Laboratoire Ecologie, Systématique et Evolution, UMR8079, Orsay, F-91405, Paris, France.
authors.forename: Z
authors.initials: Z
authors.lastname: Toghranegar
authors.forename: S
authors.initials: S
authors.lastname: Nadot
authors.forename: B
authors.initials: B
authors.lastname: Albert
mesh_terms: D056130:Gametogenesis, Plant / Q000502:physiology*; D005936:Glucans / Q000378:metabolism*; D019684:Magnoliopsida / Q000502:physiology*; D011058:Pollen / Q000502:physiology*
chemical_list: D005936:Glucans; C048306:callose
keywords: Acoraceae; Alstroemeriaceae; Amaryllidaceae; Asparagaceae; Butomaceae; Callose; Commelinaceae; Liliaceae; Xanthorrhoeaceae; aperture pattern; microsporogenesis; monocots; pollen