A Morphogenetic Model Accounting for Pollen Aperture Pattern in Flowering Plants

Aperture variation in the pollen ofNelumbo(Nelumbonaceae)

“…Similar shifts in developmental timing have been invoked as responsible for variation in other key features of pollen morphology (Blackmore & Crane, 1998). Similarly, Ressayre et al (1998Ressayre et al ( , 2000aRessayre et al ( , b, 2003Ressayre et al ( , 2005 have related differences in the mature form of pollen apertures to changes in the deposition of the callose wall between daughter cells in a tetrad. In the case of Nelumbo, differentiation of the apertures appears delayed until relatively late in pollen development (Kreunen & Osborn, 1999).…”

“…The number, position and shape of apertures in mature pollen grains are the result of a series of developmental processes that include the type of microsporogenesis (linked to the resulting tetrad shape) as well as the processes that determine pollen polarity and govern pollen wall formation (Ressayre et al, 1998(Ressayre et al, , 2002a(Ressayre et al, , b, 2003Penet et al, 2005). No direct observations have been made on the type of microsporogenesis present in Nelumbo; the interpretations in all published studies (Kuprianova, 1979;Kreunen & Osborn, 1999) are based on observations of tetrad shape in mature or developing grains.…”

“…Among angiosperms there are two main kinds of microsporogenesis: successive (whereby callose cell walls are formed after meiosis I and then again after meiosis II) or simultaneous (whereby both nuclear divisions take place before callose cell walls are formed) (Ressayre et al, 1998(Ressayre et al, , 2002a(Ressayre et al, , b, 2003Furness & Rudall, 2004;Penet et al, 2005). Simultaneous microsporogenesis allows for all microspores to adopt positions within the tetrad as far away from their neighbours as possible, thus forming tetrahedral tetrads.…”

Systems Biology Approaches Towards the Prediction of Prospective Novel Plant System-Derived Products or Services

“…The author attempts to explain the duplication of an aperture of a three aperturate pollen grain leads to formation of four apertures and heterogeneous tetrads [16]. The algorithm builds a vector field inside a ball that represents the cells centering the nuclei.…”

“…The algorithm builds a vector field inside a ball that represents the cells centering the nuclei. The space in the ball is divided to make domains in each attractor where each attractor has particles that cannot move to other attractors but can remain moving in the same attractor giving rise to arms and the points were the arms meet are considered to indicate the position of aperture [16]. A more robust approach is the model of plant competition in an agronomic perspective that considers the plant competition fundamentals, plant-weed interaction and the dynamics of weeds in crops.…”