Over evolutionary time, the morphology of angiosperm pollen has evolved toward an increasing number of apertures, among other things. From a neo-Darwinian point of view, this means that (i) some polymorphism for aperture number must exist and (ii) there must be some fitness increase associated with increasing the aperture number. Pollen types with different aperture numbers often occur in the s...

habit and pollen morphology were studied in four taxa belonging to astragalus sect. macrophyllium in iran. data obtained from pollen morphology support the phenetic grouping based on habit morphology. in addition, meiotic chromosome number and behavior were analyzed in two species of the section. the species were cytogenetically analyzed and found to be tetraploid and possess a 2n = 4x = 32 chr...

PREMISE OF THE STUDY Pollen grains are subject to intense dehydration before dispersal. They rehydrate after landing on a stigma or when placed in humid environment by absorbing water from the stigma or surroundings. Resulting fluctuations in water content cause pollen grains to undergo significant changes in volume. Thus, morphological or structural adaptations might exist to help pollen adjus...

The objective of this study was to determine the effect of application of pesticides on morphology, viability, and germination of pollen grains of Blackberry (Rubus glaucus Benth.) and Tree tomato (Solanum betaceum Cav.). The study was performed at Patate, Tungurahua province, Ecuador and was divided into two phases. Phase one dedicated to the study of morphology, viability, and identification ...

The genus Crocus L. (Iridaceae) comprises about 80 species distributed mainly in the Mediterranean region. It is widely dispersed in Turkey; at present about 67 taxa (including subspecies and varieties) are recognized there (Mathew, 1984, 1988, 1995, 2000; Kerndorff and Pasche, 2003, 2004). The Turkish Crocus species have received attention by several workers, who have concentrated mainly on mo...