Comparative study of pollen morphology and exine ultrastructure in tetrads, octads and polyads of the genus Mimosa (Leguminosae)

Palynology ◽  
2018 ◽  
Vol 43 (2) ◽  
pp. 188-212
Author(s):  
Montserrath Medina-Acosta ◽  
Rosaura Grether ◽  
Angélica Martínez-Bernal ◽  
Elia Ramírez-Arriaga
2017 ◽  
Vol 7 (4) ◽  
pp. 234-239
Author(s):  
M. S. Yamburov ◽  
S. B. Romanova ◽  
A. S. Prokopyev

The comparative study results of pollen morphology of the mutational witches’ brooms and the normal part of the tree crown in Scots pine are presented. There is a decrease of pollen grains size, especially the sacci, in witches’ brooms. The witches’ brooms with more intensive branching have more expressive changes. Also, the witches’ brooms have more abnormal pollen grains. The data on the occurrence about 10 anomalous morphotypes of pollen grains are reported, most of that are related to the abnormal development of succi: different size of sacci, deformed sacci, reduced sacci, fused sacci, additional sacci, compress sacci, lack of one or both sacci. A high percentage of anomalies in the sacci development may be associated with less developed reticular sculpture of ectexine in witches’ brooms pollen.


1999 ◽  
Vol 77 (5) ◽  
pp. 744-767
Author(s):  
Danielle Lobreau-Callen ◽  
Joël Jérémie ◽  
Maria Suarez-Cervera

This palynological study of the genus Utricularia (Lentibulariaceae) deals with 39 species spread through 26 of the 35 sections that compose the genus. The pollen varies from tricolporate to zonocolporate or to zonoporate. The tectum is smooth, rarely ornamented (SEM). Nine pollen types are distinguished of which six have been studied with the TEM. The tectum is regular, the infratectum generally granular. The foot-layer is thick if the number of apertures is reduced and thin or absent if the endoapertures form an endocingulum. The endexine is thick if the foot-layer is thin, and made up of lamellae and rarely of costae bordering the endoapertures. In the porate pollen, the foot-layer and endexine are absent. Diverse in the terrestrial and lithophytic species, the pollen tends to be oblate and planaperturate in the epiphytes, zonocolporate with numerous apertures in the floating aquatic species, and ornamented in those of flowing water. The species considered the most primitive are terrestrial with tricolporate pollen. All the other types are derived, especially those with a significant increase in the number of apertures, associated or not with the absence of a foot-layer or an endexine. In the genus Utricularia and the Lentibulariaceae in general, the variation in pollen is much less related to habitat than to the evolutionary history of each species.Key words: pollen, morphology, exine, ultrastructure, Utricularia, Lentibulariaceae.


2019 ◽  
Vol 33 (3) ◽  
pp. 584-591 ◽  
Author(s):  
Lidian Ribeiro de Souza ◽  
Francisco de Assis Ribeiro dos Santos ◽  
Daniela Santos Carneiro-Torres

2020 ◽  
Author(s):  
Bruno Oliveira Ferreira de Souza ◽  
Éve‐Marie Frigon ◽  
Robert Tremblay‐Laliberté ◽  
Christian Casanova ◽  
Denis Boire

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