Cytology of Elymus panormitanus and its F1 hybrids with Pseudoroegneria spicata, Elymus caninus, and Elymus dentatus ssp. ugamicus

Genome ◽  
1988 ◽  
Vol 30 (6) ◽  
pp. 879-884 ◽  
Author(s):  
Kevin B. Jensen ◽  
Stephan L. Hatch
Keyword(s):  
Seed Set ◽  
Karyotype Analysis ◽  
The United States ◽  
Intergeneric Hybrids ◽  
F1 Hybrids ◽  
Genomic Constitution ◽  
Pseudoroegneria Spicata ◽  
Elymus Caninus ◽  
Modified Forms ◽  
Sterile Hybrids

Three accessions of Elymus panormitanus (Parl.) Tzvelev were introduced into the United States in 1967 from Iraq and Turkey. A study was undertaken to describe the cytological behavior, mode of reproduction, cytology and fertility of E. panormitanus and its F1 hybrids with "analyzer" species, and genomic formula. Chromosome pairing was studied at meta-phase I in a series of interspecific and intergeneric hybrids to characterize the genomic constitution of E. panormitanus. All plants of E. panormitanus studied were 2n = 28, and averaged 13.96 bivalents per cell, suggesting that E. panormitanus is an allotetraploid with two different genomes. Seed set under controlled pollination indicated that E. panormitanus is highly self-compatible. Hybrids between E. panormitanus and the following analyzer species (with known genomic constitution) were obtained: Pseudoroegneria spicata (Pursh.) A. Love, 2n = 14, SS; Elymus caninus (L.) L., 2n = 28, SSHH; Elymus dentatus (Hook, f.) Tzvelev ssp. ugamicus (Drob.) Tzvelev, 2n = 28, SSYY. All hybrids were highly sterile. Hybrids between E. panormitanus and P. spicata, E. caninus, and E. dentatus ssp. ugamicus averaged 3.93, 3.70, and 7.28 bivalents per cell, respectively. Meiotic data in this series of F1 hybrids and karyotype analysis of E. panormitanus suggested that the genomic formula for E. panormitanus can tentatively be written as SpSpYpYp, indicating that both genomes are modified forms of the S and Y genomes found in the East Asian SY polyploids.Key words: Triticeae, Elymus, phylogeny, hybrids, intergeneric.

Cytology, fertility, and origin of Elymus abolinii (Drob.) Tzvelev and its F1 hybrids with Pseudoroegneria spicata, E. lanceolatus, E. dentatus ssp. ugamicus, and E. drobovii (Poaceae: Triticeae)

Genome ◽  
1989 ◽  
Vol 32 (3) ◽  
pp. 468-474 ◽  
Author(s):  
Kevin B. Jensen
Keyword(s):  
Chromosome Pairing ◽  
Phylogenetic Relationships ◽  
Morphological Characters ◽  
Intergeneric Hybrids ◽  
Natural Hybridization ◽  
F1 Hybrids ◽  
Direct Measure ◽  
Species Hybrid ◽  
Pseudoroegneria Spicata ◽  
Hybrid Complex

Chromosome pairing and hybrid fertility provide a direct measure of phylogenetic relationships between different taxa. Five accessions of Elymus abolinii (Drob.) Tzvelev were studied to (i) determine their reproductive characteristics; (ii) describe phylogenetic relationships and genomic affinities through chromosome pairing and fertility in the species and species hybrid complex with closely related taxa; (iii) evaluate the morphological variation between related taxa; and (iv) propose a possible origin for E. abolinii. Interspecific and intergeneric hybrids with E. abolinii were obtained from the following "analyzer" parents: Pseudoroegneria spicata (Pursh) A. Love, E. lanceolatus (Scribn. &Smith) Gould, E. dentatus (Hook, f.) Tzvelev ssp. ugamicus (Drob.) Tzvelev, and E. drobovii (Nevski) Tzvelev. The results showed that E. abolinii is an allotetraploid forming 14 bivalents in 95% of the cells, and it is self-fertilizing. Chromosome pairing within the species hybrid complex demonstrated that E. abolinii comprises the S and Y genomes, with close affinities to other eastern Chinese taxa that comprise the S and Y genomes. Multivariate analysis of morphological characters supports the hypothesis that E. abolinii originated from a natural hybridization between E. dentatus ssp. ugamicus and E. gmelinii Ledeb.) Tzvelev, followed by a possible backcross with E. dentatus ssp. ugamicus.Key words: genome, meiosis, chromosome pairing, morphology, hybrid, Triticeae.

Cytogenetics of Elymus caucasicus and Elymus longearistatus (Poaceae: Triticeae)

Genome ◽  
1991 ◽  
Vol 34 (6) ◽  
pp. 860-867 ◽  
Author(s):  
Kevin B. Jensen ◽  
Richard R.-C. Wang
Keyword(s):  
Chromosome Pairing ◽  
Interspecific Hybrid ◽  
Intergeneric Hybrids ◽  
Cytological Analysis ◽  
Meiotic Behavior ◽  
Pseudoroegneria Spicata ◽  
Central Asian ◽  
Elymus Lanceolatus

Two accessions of Elymus caucasicus (Koch) Tzvelev and three accessions of Elymus longearistatus (Boiss.) Tzvelev were studied to determine the meiotic behavior and chromosome pairing in the two taxa, their interspecific hybrid, and their hybrids with various "analyzer" parents. Interspecific and intergeneric hybrids of the target taxa were obtained with the following analyzer species: Pseudoroegneria spicata (Pursh) A. Löve (2n = 14, SS), Pseudoroegneria libanotica (Hackel) D. R. Dewey (2n = 14, SS), Hordeum violaceum Boiss. &Hohenacker (2n = 14, HH) (= Critesion violaceum (Boiss. &Hohenacker) A. Löve), Elymus lanceolatus (Scribn. &Smith) Gould (2n = 28, SSHH), Elymus abolinii (Drob.) Tzvelev (2n = 28, SSYY), Elymus pendulinus (Nevski) Tzvelev (2n = 28, SSYY), Elymus fedtschenkoi Tzvelev (2n = 28, SSYY), Elymus panormitanus (Parl.) Tzvelev (2n = 28, SSYY), and Elymus drobovii (Nevski) Tzvelev (2n = 42, SSHHYY). Cytological analysis of their F1 hybrids showed that E. caucasicus and E. longearistatus were allotetraploids comprising the same basic genomes. Chromosome pairing in the E. caucasicus × P. libanotica hybrid demonstrated that the target taxa contained the S genome, based on 6.1 bivalents per cell. The lack of chromosome pairing, less than one bivalent per cell, in the E. longearistatus × H. violaceum hybrid showed that the H genome was absent. Increased pairing in the tetraploid and pentaploid hybrids when the Y genome was introduced indicated that the second genome in the two taxa was a segmental homolog of the Y genome. The S and Y genomes in E. caucasicus and E. longearistatus have diverged from each other and from those in many of the eastern and central Asian SY tetraploids.Key words: genome, meiosis, chromosome pairing, morphology, hybrid, Triticeae.

Genome discrimination by in situ hybridization in Icelandic species of Elymus and Elytrigia (Poaceae: Triticeae)

Genome ◽  
2001 ◽  
Vol 44 (2) ◽  
pp. 275-283 ◽  
Author(s):  
Marian Ørgaard ◽  
Kesara Anamthawat-Jónsson
Keyword(s):  
In Situ Hybridization ◽  
Fluorescence In Situ Hybridization ◽  
Genomic Dna ◽  
Genomic In Situ Hybridization ◽  
Pseudoroegneria Spicata ◽  
Genome Constitution ◽  
Elytrigia Repens ◽  
Elymus Caninus ◽  
Elymus Species

The genome constitution of Icelandic Elymus caninus, E. alaskanus, and Elytrigia repens was examined by fluorescence in situ hybridization using genomic DNA and selected cloned sequences as probes. Genomic in situ hybridization (GISH) of Hordeum brachyantherum ssp. californicum (diploid, H genome) probe confirmed the presence of an H genome in the two tetraploid Elymus species and identified its presence in the hexaploid Elytrigia repens. The H chromosomes were painted uniformly except for some chromosomes of Elytrigia repens which showed extended unlabelled pericentromeric and subterminal regions. A mixture of genomic DNA from H. marinum ssp. marinum (diploid,Xa genome) and H. murinum ssp. leporinum (tetraploid,Xu genome) did not hybridize to chromosomes of the Elymus species or Elytrigia repens, confirming that these genomes were different from the H genome. The St genomic probe from Pseudoroegneria spicata (diploid) did not discriminate between the genomes of the Elymus species, whereas it produced dispersed and spotty hybridization signals most likely on the two St genomes of Elytrigia repens. Chromosomes of the two genera Elymus and Elytrigia showed different patterns of hybridization with clones pTa71 and pAes41, while clones pTa1 and pSc119.2 hybridized only to Elytrigia chromosomes. Based on FISH with these genomic and cloned probes, the two Elymus species are genomically similar, but they are evidently different from Elytrigia repens. Therefore the genomes of Icelandic Elymus caninus and E. alaskanus remain as StH, whereas the genomes of Elytrigia repens are proposed as XXH.Key words: Elymus, Elytrigia, H genome, St genome, in situ hybridization.

Production of F1 hybrids using ethrel-induced male sterility in Indian mustard (Brassica juncea (L.) Coss.)

1983 ◽  
Vol 101 (2) ◽  
pp. 453-455 ◽  
Author(s):  
S. S. Banga ◽  
K. S. Labana
Keyword(s):  
Male Sterility ◽  
Brassica Juncea ◽  
Seed Set ◽  
Indian Mustard ◽  
F1 Hybrids ◽  
Carry Over ◽  
Circular Design ◽  
Yield Trials ◽  
East West ◽  
Plot Design

SUMMARYThe effect of field layout and the orientation of seed-production blocks on outcrossing rates was investigated in Indian mustard. The study incorporated three male:female combinations, i.e. 1:2, 1:3 and 2:4 laid in east–west, north–south and circular directions. The experimental material consisted of four test cultivars (RLM 198, RLM 514, Varuna and TM 4) in a split-plot design. Male sterility was achieved by spraying 0·25% (v/v) ethrel twice before the emergence of the first flowering shoots. The proportion of hybrid seed set was maximal in the 2:4 combination in a circular design. Outcrossing varied from 19 to 79%. Heterosis was evident in yield trials, but F1 hybrids showed carry-over effects due to ethrel treatment. It is argued that ethrelinduced male sterility has only a limited role in screening parental combinations for their yield assessment.

Gene flow between introduced and native Eucalyptus species: crossability of native Tasmanian species with exotic E. nitens

2005 ◽  
Vol 53 (5) ◽  
pp. 465 ◽  
Author(s):  
R. C. Barbour ◽  
B. M. Potts ◽  
R. E. Vaillancourt
Keyword(s):  
Gene Flow ◽  
Native Species ◽  
Seed Set ◽  
Pollen Competition ◽  
F1 Hybrids ◽  
Eucalyptus Species ◽  
F1 Hybrid ◽  
Genetic Pollution ◽  
Morphometric Analyses ◽  
Natural Hybridisation

Eucalyptus nitens (Deane & Maiden) Maiden has been extensively introduced to the island of Tasmania for plantation purposes. Natural hybridisation with two native species has already been confirmed and this study aimed to determine which other Tasmanian native species could potentially hybridise with E. nitens. Controlled and supplementary pollinations with E. nitens pollen were undertaken on all Tasmanian native species that are potentially at risk of exotic gene flow and hence genetic pollution. Across the seven species tested by using controlled pollinations, seed set per flower, following E. nitens pollinations, was significantly less than for intraspecific outcross pollinations. No significant differences were evident in the percentage of seed that germinated or the percentage of germinants that grew into healthy seedlings in the glasshouse. Hybridity was verified by morphometric analyses and F1 hybrid seedlings were clearly differentiated from parental species and generally intermediate in morphology. Supplementary E. nitens pollination of open-pollinated native flowers was conducted to simulate natural pollination where pollen competition would occur. Seven of the fifteen species tested produced F1 hybrids in this case; however, further crossing is required to verify failed cross combinations. Although E. nitens can potentially hybridise with many native species, the results from both supplementary and controlled pollinations suggest the presence of post-pollination barriers of varying strength that need to be considered in assessing the risk of exotic gene flow from plantations.

scholarly journals Miscanthus Anderss. Produces Viable Seed in Four USDA Hardiness Zones

1999 ◽  
Vol 17 (3) ◽  
pp. 137-140 ◽  
Author(s):  
Mary Hockenberry Meyer ◽  
Courtney L. Tchida
Keyword(s):  
United States ◽  
Invasive Plants ◽  
Seed Set ◽  
The United States ◽  
Viable Seed ◽  
Invasive Potential ◽  
Climatic Zones ◽  
Laboratory Results

Abstract Forty-one taxa of Miscanthus grown in USDA Hardiness Zones 4, 5, 6, and 7 were examined in 1996 and 1997 for seed set and viability. Although laboratory results varied widely between years, climatic zones, and cultivars, many plants set viable seed. Eleven types had <18% viable seed, including ‘Morning Light’, ‘Variegatus’ and ‘Zebrinus’, and appear to represent the least risk for becoming invasive plants, especially in northern climates. Other characteristics of Miscanthus are discussed in terms of invasive potential in the United States.

scholarly journals Phenotypic Characterization and RT-qPCR Analysis of Flower Development in F1 Transgenics of Chrysanthemum × grandiflorum

Plants ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1681
Author(s):  
Saba Haider ◽  
Muhammad Ajmal Bashir ◽  
Umer Habib ◽  
Yike Gao ◽  
Muhammad Rashid Shaheen ◽  
...  
Keyword(s):  
Transgenic Plants ◽  
Gene Silencing ◽  
Flower Development ◽  
Rna Degradation ◽  
Intergeneric Hybrids ◽  
F1 Hybrids ◽  
Phenotypic Characterization ◽  
Pcr Analysis ◽  
Cross Hybridization

Gene silencing is the epigenetic regulation of any gene in order to prevent gene expression at the transcription or translation levels. Among various gene silencing techniques, RNA silencing (RNAi) is notable gene regulation technique that involves sequence-specific targeting and RNA degradation. However, the effectiveness of transgene-induced RNAi in F1 generation of chrysanthemum has not been studied yet. In the current study, we used RNAi-constructed CmTFL1 (white-flowered) and CmSVP overexpressed (yellow flowered) transgenic plants of previously conducted two studies for our experiment. Cross hybridization was performed between these intergeneric transgenic and non-transgenic plants of the winter-growing chrysanthemum selection “37” (light pink flowered). The transgene CmSVP was confirmed in F1 hybrids by RT-PCR analysis, whereas hybrids of CmTFL1 parental plants were non-transgenic. Besides this, quantitative real-time PCR (qPCR) was used to explain the molecular mechanism of flower development using reference genes. Intergeneric and interspecific hybrids produced different colored flowers unlike their respective parents. These results suggest that generic traits of CmSVP overexpressed plants can be transferred into F1 generations when crossed with mutant plants. This study will aid in understanding the breeding phenomenon among intergeneric hybrids of chrysanthemum plants at an in vivo level, and such transgenics will also be more suitable for sustainable flower yield under a low-light production system.

scholarly journals DESIGNING SCHEMES FOR SEED PRODUCTION OF SPRING RAPE F1 HYBRIDS BASED ON CMS

2020 ◽  
Vol 2020 (4) ◽  
pp. 89-95
Author(s):  
Nina Markelova ◽  
Albina Vlasova ◽  
Vsevolod Cherepanov ◽  
Vladimir Karpachev
Keyword(s):  
Cytoplasmic Male Sterility ◽  
Seed Production ◽  
Seed Yield ◽  
Inbred Lines ◽  
F1 Hybrids ◽  
Yield Traits ◽  
Ogura Cytoplasm ◽  
Spring Rape ◽  
Hybrid Forms ◽  
Sterile Hybrids

As the result of the research conducted in 2018–2020 at the All-Russian Rapeseed Research Institute, a scheme of primary seed farming of self-pollinated lines and F1 hybrids of spring rape has been developed, over 45 varieties have been created, including self-pollinated lines, simple interline and three-line hybrids. A comparative appraisal of spring rape inbred lines (female parents) and hybrids of the two most common systems of cytoplasmic male sterility (CMS) – Polima (LHS-1, LMS-1, LMS-2) and Ogura (LCS-4, LCS-5, LCS-6), was made. Yield traits distinctiveness in simple sterile hybrids of Polima and Ogura types was studied; it has been asserted that when compared to inbred maternal lines the traits predominate in hybrids, the indices are higher by 24.8% in the hybrids based on sterile Ogura cytoplasm and by 10.7% in the hybrids on sterile Polima cytoplasm. In our studies, self-pollinated lines, the maternal components of the hybrids, are inferior to the hybrids in terms of crude fat content in seeds, it is 6.5% lower than in the hybrid forms for the CMS Pol system and 17.3% lower for the forms of the CMS Ogu system. It was determined that the seed yield of CMS systems hybrids of Ogura type is on average 22.0% higher than the seed yield of Polima hybrids. The starting material for primary seed production of rapeseed hybrids based on CMS has been developed.

A study on genomic relationships of Agropyron trachycaulum with Elymus scabriglumis, E. innovatus, and Hordeum procerum

Genome ◽  
1988 ◽  
Vol 30 (4) ◽  
pp. 525-528 ◽  
Author(s):  
P. K. Gupta ◽  
H. S. Balyan ◽  
George Fedak
Keyword(s):  
Chiasma Frequency ◽  
Embryo Rescue ◽  
Intergeneric Hybrids ◽  
Genomic Constitution ◽  
Rescue Technique ◽  
Genomic Relationships ◽  
Chromosome Associations ◽  
Synthetic Hybrids ◽  
The Mean ◽  
Agropyron Trachycaulum

Synthetic hybrids of Agropyron trachycaulum (2n = 4x = 28) with Elymus scabriglumis (2n = 6x = 42), E. innovatus (2n = 4x = 28), and Hordeum procerum (2n = 6x = 42) were produced through the embryo rescue technique, at relative frequencies of 7.1, 4.2, and 1.8%, respectively, of pollinated florets. The mean chromosome associations in two hybrids with E. scabriglumis was 11.71II + 1.47III + 0.15IV (mean chiasma frequency = 22.75), in one hybrid with H. procerum was 7.27II + 0.63III + 0.09IV (mean chiasma frequency = 10.20) and in a hybrid with E. innovatus was 2.8II (2.19 chiasma frequency). The data suggested two common genomes (S and H) with E. scabriglumis, one common genome (H) with H. procerum, and no common genome with E. innovatus. The evidence obtained suggested a SSHHYY genomic constitution for E. scabriglumis and two genomes different from SH for E. innovatus. The evidence also suggested that in H. procerum there may not be two related genomes present (derived from H. jubatum) as speculated in some earlier studies.Key words: intergeneric hybrids, Agropyron, Elymus, Hordeum, chromosome pairing.

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