Développement de l'anthère et du grain de pollen chez une espèce sauvage apparentée à la canne à sucre (Saccharum spontaneum)

A study of the histocytological characteristics of anthers and pollen development of fertile male genotypes of Saccharum spontaneum L. support the division of microsporogenesis into nine distinct stages: premeiosis, meiosis and tetrad, young uninucleate microsporal stage, median uninucleate microsporal stage, median vacuolized uninucleate microsporal stage, late vacuolized uninucleate microsporal stage, first pollinic mitosis, second pollinic mitosis, mature pollen. Pollen grains are subspherical, monosporal, operculated with verrucose type ornamentations. A secretory type tapetum, present from the very first microsporal stages, is covered with orbicules persisting until anthesis. Keywords: Saccharum spontaneum, microsporogenesis, pollen, tapetum. [Journal translation]

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A Cytological Study of Anther and Pollen Development in Chinquapin (Castanea henryi)

HortScience ◽

10.21273/hortsci14934-20 ◽

2020 ◽

Vol 55 (6) ◽

pp. 945-950

Author(s):

Weiping Zhong ◽

Zhoujun Zhu ◽

Fen Ouyang ◽

Qi Qiu ◽

Xiaoming Fan ◽

...

Keyword(s):

Pollen Development ◽

Lipid Droplets ◽

Morphological Characteristics ◽

Pollen Grains ◽

Middle Layer ◽

Anther Development ◽

Mature Pollen ◽

Anther Wall ◽

Male Flowers ◽

Microspore Stage

The normal development of anthers and the formation of functional pollen are the prerequisites for successful pollination and fertilization. In this study, we observed dynamic changes in inflorescence and anther development in the chinquapin (Castanea henryi) using stereomicroscopy, light microscopy, and transmission electron microscopy. We found that cytokinesis during meiosis in microsporocytes was of the simultaneous type, and that the tetrads were mainly tetrahedral. Mature pollen grains contained two cells with three germ pores. The anther wall was of the basic type and composed of epidermis, endothecium, middle layers, and tapetum. Mature anthers had no middle layer and tapetum. The tapetum was of the glandular type. At the early microspore stage, a large number of starch granules appeared in the endothecium, which was deformed at the late microspore stage. Lipid droplets appeared in tapetum during the early microspore stage, and a few lipid droplets were still found during tapetum degeneration. The mature pollen accumulated a large amount of starch and lipids. These findings demonstrated that the anther wall provides nutrients and protection for pollen development. There is relatively stable correspondence between the external morphological characteristics of male flowers and internal structure of anther development.

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Studia nad kariologią i rozwojem pyłku kilku odmian Medicago saliva L. Cz. I [Studies on karyology and pollen development in several varieties of Medicago sativa L. Part I]

Acta Agrobotanica ◽

10.5586/aa.1971.020 ◽

2015 ◽

Vol 24 (2) ◽

pp. 319-341

Author(s):

K. Bijok ◽

E. Adamkiewicz ◽

L. Grygorczyk

Keyword(s):

Medicago Sativa ◽

Meiotic Division ◽

Pollen Development ◽

Pollen Grains ◽

Mature Pollen ◽

Meiotic Stage ◽

Medicago Saliva ◽

Medicago Sativa L

At the stage of diakinensis and metaphase of the first meiotic division, conjugating chromosomes in the form of bivalents were always observed. At the pre-meiotic stage some of .the mother pollen cells underwent degeneration (in 'Australian' var. 17% in 'Warminska' 20%, in 'Kleszczewska' 23%, in 'Grimma' 30% and in 'Miechowska' 40%). In the degenerating mother pollen cells no meiotic division were observed. In the surviving mother pollen cells, meiotic division were found to be normal. The mature pollen grains were trinucleate.

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Pollen development in Douglas fir (Pseudotsuga menziesii)

Canadian Journal of Botany ◽

10.1139/b71-178 ◽

1971 ◽

Vol 49 (8) ◽

pp. 1263-1266 ◽

Cited By ~ 8

Author(s):

John N. Owens ◽

Marje Molder

Keyword(s):

Pseudotsuga Menziesii ◽

Pollen Development ◽

Pollen Grains ◽

Spore Wall ◽

Douglas Fir ◽

Mature Pollen ◽

Stalk Cell ◽

Wall Structure ◽

Normal Sequence ◽

Tube Cell

The normal sequence of pollen development in Douglas fir is described and is essentially the same as that for Pinus. Mature pollen grains normally consist of five cells: two lens-shaped prothallial cells, a stalk cell, a body cell, and a large tube cell. The normal sequence of development is described as well as the structure and histochemistry of the spore wall. Possible reasons are given for earlier misinterpretations of pollen development and spore wall structure in Douglas fir.

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Resolution of Channels in the Exine by Translocation of Colloidal Iron

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100065808 ◽

1971 ◽

Vol 29 ◽

pp. 352-353

Author(s):

John R. Rowley

Keyword(s):

Phosphate Buffer ◽

Pollen Development ◽

Osmium Tetroxide ◽

Pollen Grains ◽

Deionized Water ◽

Colloidal Iron ◽

Fixed Material ◽

Epilobium Angustifolium ◽

Untreated Material ◽

Microspore Mitosis

The morphology of the exine of many pollen grains, at the time of flowering, is such that one can suppose that transport of substances through the exine occurred during pollen development. Holes or channels, microscopic to submicroscopic, are described for a large number of grains. An inner part of the exine of Epilobium angustifolium L. and E. montanum L., which may be referred to as the endexine, has irregularly shaped channels early in pollen development although by microspore mitosis there is no indication of such channeling in chemically fixed material. The nucleus in microspores used in the experiment reported here was in prophase of microspore mitosis and the endexine, while lamellated in untreated grains, did not contain irregularly shaped channels. Untreated material from the same part of the inflorescence as iron treated stamens was examined following fixation with 0.1M glutaraldehyde in cacodylate-HCl buffer at pH 6.9 (315 milliosmoles) for 24 hrs, 4% formaldehyde in phosphate buffer at pH 7.2 (1,300 milliosmoles) for 12 hrs, 1% glutaraldehyde mixed with 0.1% osmium tetroxide for 20 min, osmium tetroxide in deionized water for 2 hrs and 1% glutaraldehyde mixed with 4% formaldehyde in 0.1M cacodylate-HCl buffer at pH 6.9 for two hrs.

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