scholarly journals Cytological Studies of Natural Intergeneric Hybrids and Their Parental Species in the Moss Genera, Astomum and Weissia

1972 ◽  
Vol 59 (3) ◽  
pp. 382 ◽  
Author(s):  
Lewis E. Anderson ◽  
Betty E. Lemmon
Keyword(s):  
Parental Species ◽  
Intergeneric Hybrids

Intergeneric hybrids between Thinopyrum and Psathyrostachys (Triticeae)

Genome ◽  
1990 ◽  
Vol 33 (6) ◽  
pp. 845-849 ◽  
Author(s):  
Richard R.-C. Wang
Keyword(s):  
Genome Analysis ◽  
Parental Species ◽  
Intergeneric Hybrids ◽  
Meiotic Pairing ◽  
Green Leaves ◽  
Psathyrostachys Juncea ◽  
Basic Genome ◽  
Chromosome Associations ◽  
Thinopyrum Elongatum ◽  
First Time

Intergeneric hybrids were synthesized for the first time from the diploid crosses Thinopyrum elongatum (JeJe) × Psathyrostachys juncea (NjNj), T. elongatum × P. fragilis (NfNf), T. bessarabicum (JbJb) × P. huashanica (NhNh), and T. bessarabicum × P. juncea, as well as from a cross between the amphidiploid of T. bessarabicum × T. elongatum (JbJbJeJe) and P. juncea. Spikes of these hybrids are morphologically intermediate between those of the parental species. Double spikelets occurred occasionally at central nodes of the spikes. Glaucous blue leaves appeared in the F1 only in the cross T. bessarabicum × P. huashanica, suggesting that the gene(s) for glaucous blue leaves in T. bessarabicum is (are) recessive to a gene(s) for green leaves in P. juncea but is (are) dominant to that for yellowish green leaves in P. huashanica. Meiotic pairing at metaphase I in these diploid (JN) and triploid (JJN) hybrids revealed a very low level of homology between the basic J and N genome. Therefore, the J and N genomes are nonhomologous and justifiably represented by different genome symbols. The triploid hybrids exhibited a pattern of chromosome associations that substantiated the earlier conclusion that the genomes in T. bessarabicum and T. elongatum are two versions of a basic genome (J). These hybrids will be useful in genome analysis, forming new Leymus species with the J and N genomes and broadening the diversity in the genus Pascopyrum with the SHJN genomes.Key words: hybrid, Thinopyrum, Psathyrostachys, genome.

HYBRIDIZATION EXPERIMENTS IN RHODEINE FISHES (CYPRINIDAE, TELEOSTEI): THE INTERGENERIC HYBRIDS OF ACHEILOGNATHUS LANCEOLATA ♂ × ACANTHORHODEUS ATREMIUS ♀ AND TANAKIA TANAGO ♂ × ACHEILOGNATHUS RHOMBEA ♀

1960 ◽  
Vol 38 (6) ◽  
pp. 1171-1173 ◽  
Author(s):  
J. J. Duyvené de Wit
Keyword(s):  
Embryonic Development ◽  
Genetic Factor ◽  
Parental Species ◽  
Intergeneric Hybrids ◽  
Free Swimming ◽  
Phylogenetic Relations ◽  
Male Phenotype

In order to study the phylogenetic relations between rhodeine species a number of interspecific and intergeneric crossings have been performed. This communication deals with the intergeneric hybrids obtained from the combinations Acheilognathus lanceolata ♂ × Acanthorhodeus atremius ♀ and Tanakia tanago ♂ × Acheilognathus rhombea ♀.From the first combination adult hybrids have been obtained which were intermediate between both parental species and showed a male phenotype. The second combination produced larvae, but a deficient yolk supply prevented them from reaching the free-swimming stage.Experimental evidence is presented for the occurrence of a dominant genetic factor in A. rhombea males, which controls the duration of embryonic development in this and other bitterling species.

First intergeneric hybrids (Psilanthus ebracteolatus Hiern x Coffea arabica L.) in coffee trees

1998 ◽  
Vol 76 (3) ◽  
pp. 542-546 ◽  
Author(s):  
E Couturon ◽  
P Lashermes ◽  
A Charrier
Keyword(s):  
Coffea Arabica ◽  
Parental Species ◽  
Morphological Characteristics ◽  
Intergeneric Hybrids ◽  
Molecular Methods ◽  
Wide Cross ◽  
Coffea Species ◽  
The Mean ◽  
Tetraploid Level ◽  
Coffea Arabica L

Intergeneric hybrids between Psilanthus ebracteolatus (2n = 22) and Coffea arabica (2n = 44) were successfully produced by crossing at the tetraploid level. Although a total of 41 plants was obtained, only nine plants survived after 5 months growth in the nursery. Hybrid status was confirmed by means of cytological and molecular methods. For most of the morphological characteristics analyzed, hybrids appeared intermediate between the two parental species. The mean production of two surviving hybrids per 100 pollinated flowers as well as their fertility are comparable with those reported for intrageneric crosses between subgenera Coffea species, and do not support the present division of coffee trees into two genera. Both the capacity of C. arabica to hybridize with P. ebracteolatus and the fertility of hybrids produced appear high enough to envisage intergeneric gene transfers from P. ebracteolatus into C. arabica.Key words: coffee, fertility, hybridization, intergeneric, polyploid, wide cross.

scholarly journals Analysis of the Meiotic Segregation in Intergeneric Hybrids of Tilapias

2012 ◽  
Vol 2012 ◽  
pp. 1-10 ◽  
Author(s):  
Etienne Bezault ◽  
Xavier Rognon ◽  
Frederic Clota ◽  
Karim Gharbi ◽  
Jean-Francois Baroiller ◽  
...  
Keyword(s):  
Parental Species ◽  
Genome Structure ◽  
Intergeneric Hybrids ◽  
Interspecific Hybridisation ◽  
Meiotic Segregation ◽  
Apparent Lack ◽  
Cichlid Species ◽  
In The Wild ◽  
Sarotherodon Melanotheron ◽  
Generation Hybrid

Tilapia species exhibit a large ecological diversity and an important propensity to interspecific hybridisation. This has been shown in the wild and used in aquaculture. However, despite its important evolutionary implications, few studies have focused on the analysis of hybrid genomes and their meiotic segregation. Intergeneric hybrids between Oreochromis niloticus and Sarotherodon melanotheron, two species highly differentiated genetically, ecologically, and behaviourally, were produced experimentally. The meiotic segregation of these hybrids was analysed in reciprocal second generation hybrid (F2) and backcross families and compared to the meiosis of both parental species, using a panel of 30 microsatellite markers. Hybrid meioses showed segregation in accordance to Mendelian expectations, independent from sex and the direction of crosses. In addition, we observed a conservation of linkage associations between markers, which suggests a relatively similar genome structure between the two parental species and the apparent lack of postzygotic incompatibility, despite their important divergence. These results provide genomics insights into the relative ease of hybridisation within cichlid species when prezygotic barriers are disrupted. Overall our results support the hypothesis that hybridisation may have played an important role in the evolution and diversification of cichlids.

scholarly journals Sequencing an F1 hybrid of Silurus asotus and S. meridionalis enabled the assembly of high-quality parental genomes

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Weitao Chen ◽  
Ming Zou ◽  
Yuefei Li ◽  
Shuli Zhu ◽  
Xinhui Li ◽  
...  
Keyword(s):  
De Novo ◽  
Parental Species ◽  
F1 Hybrids ◽  
Pelteobagrus Fulvidraco ◽  
F1 Hybrid ◽  
Short Reads ◽  
Final Assembly ◽  
Genome Complexity ◽  
Hybrid Genome ◽  
Silurus Asotus

AbstractGenome complexity such as heterozygosity may heavily influence its de novo assembly. Sequencing somatic cells of the F1 hybrids harboring two sets of genetic materials from both of the paternal and maternal species may avoid alleles discrimination during assembly. However, the feasibility of this strategy needs further assessments. We sequenced and assembled the genome of an F1 hybrid between Silurus asotus and S. meridionalis using the SequelII platform and Hi-C scaffolding technologies. More than 300 Gb raw data were generated, and the final assembly obtained 2344 scaffolds composed of 3017 contigs. The N50 length of scaffolds and contigs was 28.55 Mb and 7.49 Mb, respectively. Based on the mapping results of short reads generated for the paternal and maternal species, each of the 29 chromosomes originating from S. asotus and S. meridionalis was recognized. We recovered nearly 94% and 96% of the total length of S. asotus and S. meridionalis. BUSCO assessments and mapping analyses suggested that both genomes had high completeness and accuracy. Further analyses demonstrated the high collinearity between S. asotus, S. meridionalis, and the related Pelteobagrus fulvidraco. Comparison of the two genomes with that assembled only using the short reads from non-hybrid parental species detected a small portion of sequences that may be incorrectly assigned to the different species. We supposed that at least part of these situations may have resulted from mitotic recombination. The strategy of sequencing the F1 hybrid genome can recover the vast majority of the parental genomes and may improve the assembly of complex genomes.

Abundance of leafminers and leaf area loss by chewing herbivores in hybrids between Quercus crispula and Quercus dentata

2004 ◽  
Vol 34 (12) ◽  
pp. 2501-2507 ◽  
Author(s):  
Takahide A Ishida ◽  
Kouhei Hattori ◽  
Masahito T Kimura
Keyword(s):  
Leaf Area ◽  
Parental Species ◽  
Quercus Crispula ◽  
Species Dominance ◽  
Area Loss ◽  
Early Instar ◽  
Sap Feeding ◽  
Leaf Area Loss ◽  
Quercus Dentata ◽  
Northern Japan

We examined responses of phytophagous insects to hybrids between Quercus crispula Blume and Quercus dentata Thunberg in a natural population in northern Japan. The abundance of leafminers and leaf area loss by chewing insects in hybrids were intermediate between those in the parental species (additive mode), close to those of either of the parental species (dominance mode), or similar to those of both parental species (no difference). Hybrids were neither more susceptible nor resistant to the insect herbivores we monitored. In Phyllonorycter (Gracillariidae) species, which are specialized to either of the parental oak species, the mortality of sap-feeding early instar larvae did not differ between hybrids and the parental species. The abundance of four leafminer taxa was correlated with environmental conditions (i.e., distance from the coastal edge of the forest or the timing of budbreak) as well as genetic factors.

Detecting hybridization in African schistosome species: does egg morphology complement molecular species identification?

Parasitology ◽  
2017 ◽  
Vol 144 (7) ◽  
pp. 954-964 ◽  
Author(s):  
NELE A. M. BOON ◽  
WOUTER FANNES ◽  
SARA ROMBOUTS ◽  
KATJA POLMAN ◽  
FILIP A. M. VOLCKAERT ◽  
...  
Keyword(s):  
High Throughput Screening ◽  
Parental Species ◽  
Crossing Experiments ◽  
Transmission Potential ◽  
Human Parasite ◽  
Hybrid Detection ◽  
Field Samples ◽  
Schistosoma Bovis ◽  
Egg Morphology ◽  
Nuclear Its

SUMMARYHybrid parasites may have an increased transmission potential and higher virulence compared to their parental species. Consequently, hybrid detection is critical for disease control. Previous crossing experiments showed that hybrid schistosome eggs have distinct morphotypes. We therefore compared the performance of egg morphology with molecular markers with regard to detecting hybridization in schistosomes. We studied the morphology of 303 terminal-spined eggs, originating from 19 individuals inhabiting a hybrid zone with natural crosses between the human parasite Schistosoma haematobium and the livestock parasite Schistosoma bovis in Senegal. The egg sizes showed a high variability and ranged between 92·4 and 176·4 µm in length and between 35·7 and 93·0 µm in width. No distinct morphotypes were found and all eggs resembled, to varying extent, the typical S. haematobium egg type. However, molecular analyses on the same eggs clearly showed the presence of two distinct partial mitochondrial cox1 profiles, namely S. bovis and S. haematobium, and only a single nuclear ITS rDNA profile (S. haematobium). Therefore, in these particular crosses, egg morphology appears not a good indicator of hybrid ancestry. We conclude by discussing strengths and limitations of molecular methods to detect hybrids in the context of high-throughput screening of field samples.

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