scholarly journals Unreduced Pollen in a Wild Tetraploid Relative of Sweetpotato

1990 ◽  
Vol 115 (3) ◽  
pp. 512-516 ◽  
Author(s):  
Alfred Jones
Keyword(s):  
Ipomoea Batatas ◽  
Gene Action ◽  
Pollen Mother Cells ◽  
Unreduced Pollen ◽  
Wide Range ◽  
Natural Mechanism ◽  
Controlled Crosses ◽  
Mother Cells

Nonreduction of pollen mother ceils was observed in a wild tetraploid morning-g&y related to the sweetpotato (Ipomoea batatas L. Lam.). Techniques for identifying and determining the frequency of expression of the trait are straightforward. Previous strategies for transfer of germplasm from tetraploid (2n = 4x = 60) species to the hexaploid (2n = 6x = 90) sweetpotato involved crosses with diploids (2n = 2x = 30) to obtain triploids that then were doubled to 6x. Nonreduction of pollen mother cells probably represents the natural mechanism for raising 4x to 6x since pollination of 2x ovules with unreduced pollen (4x) should give rise to 6x progeny without need for somatic doubling. Plants carrying this trait should be useful as bridging types for introgressing genes from wild 4x species into sweetpotato. A wide range in nonreduction (up to, 74%) was recovered In progeny of controlled crosses among selected plants, but data were not sufficient to estimate gene action.

Chromosome numerical mosaicism in pearl millet (Pennisetum americanum (L.) Leeke)

1986 ◽  
Vol 28 (2) ◽  
pp. 203-206 ◽  
Author(s):  
Panuganti N. Rao ◽  
A. Nirmala
Keyword(s):  
Pearl Millet ◽  
Pennisetum Americanum ◽  
Pollen Mother Cells ◽  
Wide Range ◽  
Numerical Variation ◽  
Mother Cells

In pearl millet (Pennisetum americanum (L.) Leeke, 2n = 14), a wide range of intraplant chromosome numerical variation occurring in pollen mother cells at meiosis within the same anther, floret, or spike was found in eight plants. The types of mosaicism encountered were haploid–diploid, diploid–tetraploid, haploid–diploid–aneuploid, and diploid–tetraploid–aneuploid–teloaneuploid. Their probable mode of origin is discussed.Key words: Pennisetum, chromosomal numerical mosaicism.

In vivo karyotypic modifications following spontaneous cell fusion in maize (Zea mays L.)

1985 ◽  
Vol 27 (5) ◽  
pp. 580-585 ◽  
Author(s):  
John P. Peeters ◽  
A. J. F. Griffiths ◽  
Garrison Wilkes
Keyword(s):  
Zea Mays ◽  
Cell Fusion ◽  
Zea Mays L ◽  
Pollen Mother Cells ◽  
Supernumerary Chromosomes ◽  
Natural Mechanism ◽  
Mother Cells ◽  
Accessory Chromosomes ◽  
Cell Fusions

Spontaneous cell fusion has been detected during meiosis of pollen mother cells in a Himalayan popcorn called Sikkim Primitive. In postfusion meiotic cells one of the chromosome complements was often found to undergo modification producing a range of outcomes including aneuploidy and the formation of cells with modified supernumerary chromosomes. These abnormalities have been followed through three generations and new karyotypes containing modified supernumerary chromosomes were recovered in the F1 and F2 following the abnormal meiosis. These inherited additional chromosomes presumably arose from the cell fusions of the pollen mother cells and therefore our observations may indicate a natural mechanism for the formation of accessory chromosomes.Key words: spontaneous cell fusion, accessory chromosomes, Zea mays.

scholarly journals Oxidative Damage and Mutagenic Potency of Fast Neutron and UV-B Radiation in Pollen Mother Cells and Seed Yield ofVicia fabaL.

2013 ◽  
Vol 2013 ◽  
pp. 1-12 ◽  
Author(s):  
Ekram Abdel Haliem ◽  
Hanan Abdullah ◽  
Asma A. AL-Huqail
Keyword(s):  
Fast Neutron ◽  
Seed Yield ◽  
Dna Polymorphisms ◽  
Chromosomal Anomalies ◽  
Mutagenic Action ◽  
Mutagenic Potential ◽  
Pollen Mother Cells ◽  
Positive Effects ◽  
Wide Range ◽  
Mother Cells

In recent years, there has been a great deal of attention toward free radicals, reactive oxygen species (ROS) generated by exposure of crop plant cells to physical radiations. Henceforth, the current study was planned to compare oxidative stress and mutagenic potential of different irradiation doses of fast neutron (FN) and UV-B on meiotic-pollen mother cells (PMCs), pollen grains (PGs) and seeds yielded from irradiated faba beans seedlings. On the cytogenetic level, each irradiation type had special interference with DNA of PMC and exhibited wide range of mutagenic action on the frequency and type of chromosomal anomalies, fertility of PGs and seed yield productivity based on the irradiation exposure dose and radiation sensitivity of faba bean plants compared with un-irradiated ones. On the molecular level, SDS-PAGE and RPAD-PCR analyses of seeds yielded from irradiated seedlings exhibited distinctive polymorphisms based on size, intensity, appearance, and disappearance of polypeptides bands compared with un-irradiated ones. The total values of protein and DNA polymorphisms reached 88% and 90.80% respectively. The neutron fluency (2.3 × 106 n/cm2) and UV-B dose for 1 hr were recorded as bio-positive effects. The present study proved that genetic variations revealed by cytogenetic test could be supported by gene expression (alterations in RAPD and protein profiles).

Chromosome localization of genes that control synchronous development of pollen mother cells in wheat

Caryologia ◽  
2003 ◽  
Vol 56 (3) ◽  
pp. 275-279 ◽  
Author(s):  
Wei Li ◽  
Jun Yang ◽  
You-Fu Pan ◽  
Guang-Qin Guo ◽  
Guo-Chang Zheng
Keyword(s):  
Chromosome Localization ◽  
Pollen Mother Cells ◽  
Synchronous Development ◽  
Mother Cells

An ultrastructural study of cytomixis in tobacco pollen mother cells

PROTOPLASMA ◽  
2011 ◽  
Vol 248 (4) ◽  
pp. 717-724 ◽  
Author(s):  
Sergey R. Mursalimov ◽  
Elena V. Deineko
Keyword(s):  
Ultrastructural Study ◽  
Pollen Mother Cells ◽  
Tobacco Pollen ◽  
Mother Cells

Persisting demibivalents: a unique meiotic behaviour in Cuscuta babylonica Choisy

Genome ◽  
1987 ◽  
Vol 29 (1) ◽  
pp. 63-66 ◽  
Author(s):  
Batia Pazy ◽  
Uzi Plitmann
Keyword(s):  
Key Words ◽  
Chromosome Segregation ◽  
Meiotic Behaviour ◽  
Chromosome Behaviour ◽  
Chromosome Movement ◽  
Pollen Mother Cells ◽  
Key Words Meiosis ◽  
Mother Cells ◽  
Telomeric Association

Idiosyncratic chromosome behaviour during meiosis was found in pollen mother cells of Cuscuta babylonica Choisy, a thread-like holoparasitic herb. Its main features are among the following: (i) telomeric association between homologues through most stages of the process, which leads to persisting chromatid bivalents (= "demibivalents"); (ii) uncommon chromosome segregation in first and second anaphase; and (iii) prolonged intensified heterochromatinization. Although "regular" in its own way, this process leads to the formation of unviable products. Its further investigation might contribute to our understanding of the role of the spindle and chromosome movement in the ordinary process of meiosis. Key words: meiosis (abnormal), persisting demibivalents, Cuscuta babylonica.

TETRAPLOID TARAXACUM KOK-SAGHYZ: I. CHARACTERS OF THE LEAVES AND INFLORESCENCES IN THE PARENTAL COLCHICINE-INDUCED GENERATION

1945 ◽  
Vol 23c (4) ◽  
pp. 131-143 ◽  
Author(s):  
M. W. Bannan
Keyword(s):  
Guard Cells ◽  
Stages Of Development ◽  
Pollen Mother Cells ◽  
Mother Cells

Seedlings at different stages of development were treated with colchicine. Successive selections on the aspect of the seedlings soon after treatment, on size of the guard cells at the time of repotting, and finally, after overwintering, on counts of the chromosomes in the pollen mother cells yielded a few hundred plants with tetraploid crowns. These plants bore fewer, broader leaves and fewer, bigger inflorescences with larger achenes than did selected large-celled diploids given the same treatment, but in general the plants were no bigger. A few of the tetraploids were self-fertile (if not apomictic) early in the spring, but later all tested plants proved self-sterile.

CHROMOSOMAL ABERRATIONS IN A DIPLOID HAWORTHIA SUBFASIATA

1976 ◽  
Vol 18 (2) ◽  
pp. 281-286 ◽  
Author(s):  
C. C. Chinnappa ◽  
J. C. Semple
Keyword(s):  
Chromosomal Aberrations ◽  
Pollen Mother Cells ◽  
Mother Cells

In two diploid specimens of Haworthia subfasciata (2n = 14) several kinds of chromatid and subchromatid aberrations occurred. In some pollen mother cells E-type and U-type bridges were present. In other cells bridges and fragments were formed due to asymmetrical reunion of nonsister chromatids following breakage. A translocation involving the satellites of two L pair chromosomes was observed in one plant.

Sign in / Sign up

Export Citation Format

Share Document