In this article we will discuss about the symmetry of pollen and spore wall of plants. The term symmetry with relation to a pollen grain implies similarity of halves on either side of a median line or plane so far as aperture and ornamentation etc., are concerned. Most pollen and spores are symmetrical. As a rule, symmetric pollen and spores [...]
NPC is an artificial system of classification of pollen and spore based on the three features of aperture only, i.e. number, position and character. Erdtman and Straka (1961) proposed NPC classification and palynologists all over the world accepted it. According to NPC system each pollen grain has an arithmetic cardinal number consisting of three digits. The first digit reveals the [...]
In this article we will discuss about the aperture found in the pollen and spore wall of plants. It is a weak, preformed locus on the exine of spore and pollen through which the intra-exinous substance exits and pollen tube emerges during pollen germination. Apertures may be absent from a pollen grain or spore when they are termed as inaperturate/atreme/non-aperturate [...]