Cytological Studies in Cultivated Species of Camellia : III. Tetraploid Species and Hybrids between Diploid Species and Hexaploid Species

Genetic diversities of 106 Avena accessions, including diploid, tetraploid and hexaploid species, derived from different countries were characterized based on seed storage proteins polymorphism using SDS-PAGE. A total of 24 protein bands and 72 protein patterns were detected in all 106 accessions. The genetic similarity value varied from 0.50 to 1.00. The seed storage protein patterns were largely independent of environmental fluctuation. Accessions of the same species or with identical genome constitutions had the same or similar protein patterns. Relatively lower within-species variations were observed compared with among-species variations. The AACCDD genome hexaploid species and the AA genome diploid species were more divergent than other species, with percentages of polymorphic bands of 85.7% and 61.1% respectively. In the AA genome diploid species, the AsAs genome diploids displayed higher variations than the modified AA genome diploid species. Clustering results showed a close relationship between the hexaploid species and the AACC genome tetraploid species. The AABB genome tetraploid species were similar to the AsAs genome diploid species, with the exception of the species A. agadiriana with AABB genome constitution, which showed a close relationship with the AcAc genome diploid species A. canariensis and the polyploid species carrying the A and C genomes.

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CHROMOSOME RELATIONSHIPS BETWEEN THE CULTIVATED OAT AVENA SATIVA (6x) AND A. VENTRICOSA (2x)

Canadian Journal of Genetics and Cytology ◽

10.1139/g70-007 ◽

1970 ◽

Vol 12 (1) ◽

pp. 36-43 ◽

Cited By ~ 23

Author(s):

Hugh Thomas

Keyword(s):

Chromosome Pairing ◽

Avena Sativa ◽

Diploid Species ◽

Meiotic Behaviour ◽

Hexaploid Species ◽

C Genome

Chromosome pairing in the F1 hybrid between the cultivated oat Avena sativa and a diploid species A. ventricosa, and in the derived amphiploid, shows that the diploid species is related to one of the genomes of the hexaploid species. The amount of chromosome pairing observed in complex interamphiploid hybrids demonstrates further that A. ventricosa is related to the C. genome of A. sativa. However, the chromosomes of the diploid species have become differentiated from that of the C genome of A. sativa and this is readily apparent in the meiotic behaviour of both the F1 hybrid and the amphiploid.

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Interploid Hybridizations in Ornamental Cherries Using Prunus maackii

Journal of Environmental Horticulture ◽

10.24266/0738-2898.30.2.89 ◽

2012 ◽

Vol 30 (2) ◽

pp. 89-92

Author(s):

Margaret Pooler ◽

Hongmei Ma ◽

David Kidwell-Slak

Keyword(s):

United States ◽

Tissue Culture ◽

Cold Hardiness ◽

Diploid Species ◽

Pest Resistance ◽

The United States ◽

Tetraploid Species ◽

Genetic Base ◽

Flowering Cherry ◽

New Cultivars

The United States National Arboretum has an ongoing flowering cherry (Prunus) breeding program aimed at broadening the genetic base of cultivated ornamental cherries by developing new cultivars with disease and pest resistance, tolerance to environmental stresses, and superior ornamental characteristics. Interploid crosses, specifically 2X × 4X, in ornamental Prunus would be beneficial in breeding because they could allow introgression of traits not available in the diploid germplasm (pest resistance, cold hardiness), and could result in the creation of seedless triploids that would not set nuisance fruit and possibly have extended bloom durations. This report documents successful hybridization of P. maackii (Manchurian or Amur cherry), a tetraploid species, with P. campanulata, P. ‘Umineko’, and P. maximowiczii, all diploid species. Chromosomes of one of these resulting triploid hybrids were successfully doubled using oryzalin in tissue culture to create a hexaploid plant.

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Two closely related Tulipa species with different ploidy levels show distinct germination rates

Seed Science Research ◽

10.1017/s0960258520000057 ◽

2020 ◽

Vol 30 (1) ◽

pp. 45-48

Author(s):

Giovanni Astuti ◽

Sandro Pratesi ◽

Lorenzo Peruzzi ◽

Angelino Carta

Keyword(s):

Ploidy Level ◽

Comparative Studies ◽

Diploid Species ◽

Tetraploid Species ◽

Natural Conditions ◽

Ploidy Levels ◽

Final Length ◽

Diploid Ancestor

AbstractIn the tetraploid Tulipa sylvestris we found larger and heavier seeds that germinated around 28 days earlier than those of the diploid ancestor Tulipa pumila. The faster germination of the tetraploid species is linked to the faster growth of embryos, which reached their final length much earlier than the embryos of the diploid species. In conclusion, we argue a cautionary approach when dealing with comparative studies on ploidy level and germination to avoid misinterpretation of results when set against the natural conditions.

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Diploid ancestry and evolution of Triticum kotschyi and T. peregrinum examined using variation in repeated nucleotide sequences

Genome ◽

10.1139/g92-029 ◽

1992 ◽

Vol 35 (2) ◽

pp. 182-191 ◽

Cited By ~ 21

Author(s):

Hong-Bin Zhang ◽

Jan Dvořák ◽

J. Giles Waines

Keyword(s):

Diploid Species ◽

Nucleotide Sequences ◽

Gene Clone ◽

Rrna Gene ◽

Tetraploid Species ◽

Genome Modification ◽

Aegilops Sharonensis ◽

5S Rrna Gene ◽

Aegilops Variabilis ◽

Allotetraploid Species

Triticum peregrinum Hackel (syn. Aegilops variabilis Eig) and T. kotschyi (Boiss.) Bowden (syn. Ae. kotschyi Boiss.) are closely related allotetraploid species. Previous research indicated that they have a pair of U genomes from diploid T. umbellulatum (Zhuk.) Hackel and a pair of S genomes from a diploid species of Triticum section Sitopsis. To reinvestigate the origin of their genomes, we identified diagnostic bands in Southern blots hybridized with 27 cloned repeated nucleotide sequences and one 5S rRNA gene clone for all diploid species of Triticum L. sensu Bowden. The presence of each diagnostic band was then determined in the two tetraploid species. One pair of the genomes in both tetraploid species was found to be virtually identical to the U genome of T. umbellulatum and the other to the S1 genome of T. longissimum (Schweif. et Muschl.) Bowden or T. sharonense (Eig) Waines &Johnson (syn. Aegilops sharonensis Eig) or the internode in the phylogenetic tree of Triticum immediately preceding the divergence of T. longissimum and T. sharonense. The source of the S genomes in T. kotschyi and T. peregrinum inferred from our data differs from that inferred from cpDNA. This indicates the need to investigate the origin of nuclear genomes with nuclear genetic markers. No evidence for an extensive modification of the S genome relative to that of T. longissimum or T. sharonense was found in either tetraploid.Key words: phylogeny, polyploids, Triticum, Aegilops, Aegilops kotschyi, Aegilops variabilis, genome origin, genome modification.

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Evaluation of Arachis Species for Resistance to Tomato Spotted Wilt Virus

Peanut Science ◽

10.3146/pnut.29.2.0001 ◽

2002 ◽

Vol 29 (2) ◽

pp. 79-84 ◽

Cited By ~ 14

Author(s):

J. H. Lyerly ◽

H. T. Stalker ◽

J. W. Moyer ◽

K. Hoffman

Keyword(s):

Tomato Spotted Wilt Virus ◽

Insect Pests ◽

Disease Incidence ◽

Diploid Species ◽

Breeding Programs ◽

Arachis Species ◽

Tomato Spotted Wilt ◽

Arachis Hypogaea L ◽

Cultivated Species ◽

Wilt Virus

Abstract Tomato spotted wilt virus (TSWV) is an important plant pathogen with a wide host range, including the domesticated peanut (Arachis hypogaea L.). After initial outbreaks on peanut during the 1980s, the virus has spread to all peanut-producing states in the U.S. TSWV is transmitted by several species of thrips which are difficult to control with insecticides; therefore, control of TSWV most likely will come from selecting resistant genotypes in breeding programs. Although moderate levels of resistance have been discovered in A. hypogaea, complete virus resistance has not been found. Several Arachis species have desirable genes for plant resistances and tolerate many disease and insect pests better than the cultivated species. The objectives of this study were to (a) evaluate TSWV disease incidence and severity in accessions of Arachis species, and (b) compare levels of TSWV resistance in diploid species to selected A. hypogaea genotypes. In this study, 46 diploid Arachis spp. accessions were evaluated in the greenhouse by artificial inoculation tests for resistance to TSWV. Nine Arachis accessions were observed with no disease symptoms when TSWV isolate 10 was used as opposed to A. hypogaea lines that ranged from moderately to highly susceptible. Additional testing with more virulent isolates identified A. diogoi accession GKP 10602 and A. correntina accession GKP 9530 as highly resistant to the virus. These two accessions are being used as parents in crossing programs to incorporate TSWV resistance genes into A. hypogaea.

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CYTOTAXONOMIC STUDIES ON EREMOPYRUM

Canadian Journal of Botany ◽

10.1139/b58-047 ◽

1958 ◽

Vol 36 (4) ◽

pp. 539-546 ◽

Cited By ~ 6

Author(s):

Priyabrata Sarkar

Keyword(s):

Diploid Species ◽

The Other ◽

Tetraploid Species ◽

Generic Status ◽

Annual Habit ◽

Sterility Barrier

Five species are included in the genus Eremopyrum, namely, E. triticeum, E. hirsutum, E. buonapartis, E. orientale, and E. distans. Of these, the first two are diploids with 2n = 14, while the rest are tetraploids with 2n = 28. The karyotypes of the two diploid species are different from those of any other member, of the Triticineae in that they have chromosomes with extremely subterminal centromeres. The karyotype of each of the three tetraploid species shows a mixture of two types of chromosomes: seven pairs with extreme subterminal centromeres and the other seven pairs with median or submedian centromeres. This indicates that these are amphidiploids between triticeum–hirsutum-like taxa and perhaps some diploid species of crested Agropyron. In view of the karyotypic peculiarity, annual habit, and reported sterility barrier, the decision to give Eremopyrum generic status is supported.

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ANALYSIS OF SPECIES RELATIONSHIPS IN AVENAE BY THIN-LAYER CHROMATOGRAPHY AND DISC ELECTROPHORESIS

Canadian Journal of Genetics and Cytology ◽

10.1139/g72-038 ◽

1972 ◽

Vol 14 (2) ◽

pp. 305-316 ◽

Cited By ~ 5

Author(s):

H. C. Dass

Keyword(s):

Thin Layer ◽

Diploid Species ◽

Disc Electrophoresis ◽

Tetraploid Species ◽

Species Relationships ◽

D Genome ◽

Genome Donor ◽

A Genome ◽

Layer Chromatography ◽

Esterase Patterns

Thin-layer chromatographic studies on flavonoids, and disc electrophoretic studies on proteins and esterase isoenzymes were conducted with Avena to determine species relationships and genome homologies. Distinctness of Avena ventricosa and A. pilosa was observed in comparison to other diploid species. Closeness of the diploid species of the A. strigosa group (including hirtula and wiestii) was evident from the similarity of their protein and esterase spectra. The tetraploid species, A. barbata and A. abyssinica, were found to be very close to A. hirtula and A. strigosa, respectively, by TLC studies. Proteins and esterases also showed that the tetraploid species are very close to the A. strigosa group of diploid species. The contribution of a genome by the A. strigosa group to the tetraploids and hexaploids was confirmed. The hexaploids showed different protein and esterase patterns. The involvement of A. ventricosa as the C genome donor to the hexaploids was shown by the protein and esterase spectra. A few extra protein bands observed may have been from the D genome.

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Cytological Studies in Cultivated Species of Camellia : I. Diploid Species and their Hybrids

Ikushugaku zasshi ◽

10.1270/jsbbs1951.27.28 ◽

1977 ◽

Vol 27 (1) ◽

pp. 28-38 ◽

Cited By ~ 5

Author(s):

Katsuhiko KONDO

Keyword(s):

Diploid Species ◽

Cultivated Species

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Molecular diversity of the 5S rRNA gene and genomic relationships in the genus Avena (Poaceae: Aveneae)

Genome ◽

10.1139/g07-111 ◽

2008 ◽

Vol 51 (2) ◽

pp. 137-154 ◽

Cited By ~ 21

Author(s):

Yuan-Ying Peng ◽

Yu-Ming Wei ◽

Bernard R. Baum ◽

You-Liang Zheng

Keyword(s):

Molecular Diversity ◽

Diploid Species ◽

5S Rdna ◽

Rrna Gene ◽

D Genome ◽

Rdna Sequences ◽

Unit Classes ◽

Hexaploid Species ◽

Unit Class ◽

C Genome

The molecular diversity of the rDNA sequences (5S rDNA units) in 71 accessions from 26 taxa of Avena was evaluated. The analyses, based on 553 sequenced clones, indicated that there were 6 unit classes, named according to the haplomes (genomes) they putatively represent, namely the long A1, long B1, long M1, short C1, short D1, and short M1 unit classes. The long and short M1 unit classes were found in the tetraploid A. macrostachya , the only perennial species. The long M1 unit class was closely related to the short C1 unit class, while the short M1 unit class was closely related to the long A1 and long B1 unit classes. However, the short D1 unit class was more divergent from the other unit classes. There was only one unit class per haplome in Avena, whereas haplomes in the Triticeae often have two. Most of the sequences captured belonged to the long A1 unit class. Sequences identified as the long B1 unit class were found in the tetraploids A. abyssinica and A. vaviloviana and the diploids A. atlantica and A. longiglumis . The short C1 unit class was found in the diploid species carrying the C genome, i.e., A. clauda, A. eriantha , and A. ventricosa , and also in the diploid A. longiglumis, the tetraploids A. insularis and A. maroccana , and all the hexaploid species. The short D1 unit class was found in all the hexaploid species and two clones of A. clauda. It is noteworthy that in previous studies the B genome was found only in tetraploid species and the D genome only in hexaploid species. Unexpectedly, we found that various diploid Avena species contained the B1 and D1 units. The long B1 unit class was found in 3 accessions of the diploid A. atlantica (CN25849, CN25864, and CN25887) collected in Morocco and in 2 accessions of A. longiglumis (CIav9087 and CIav9089) collected in Algeria and Libya, respectively, whereas only 1 clone of A. clauda (CN21378) had the short D1 unit. Thus there might be a clue as to where to search for diploids carrying the B and D genomes. Avena longiglumis was found to be the most diverse species, possibly harboring the A, B, and C haplomes. The long M1 and short M1 are the unit classes typical of A. macrostachya. These results could explain the roles of A. clauda, A. longiglumis, and A. atlantica in the evolution of the genus Avena. Furthermore, one clone of the tetraploid A. murphyi was found to have sequences belonging to the short D1 unit class, which could indicate that A. murphyi might have been the progenitor of hexaploid oats and not, as postulated earlier, A. insularis. The evolution of Avena did not follow the molecular clock. The path inferred is that the C genome is more ancient than the A and B genomes and closer to the genome of A. macrostachya, the only existing perennial, which is presumed to be the most ancestral species in the genus.

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