Hybridization - Explore the Science & Experts | ideXlab

Scan Science and Technology

Contact Leading Edge Experts & Companies

Hybridization

The Experts below are selected from a list of 962037 Experts worldwide ranked by ideXlab platform

Hybridization – Free Register to Access Experts & Abstracts

P. Aleza – One of the best experts on this subject based on the ideXlab platform.

  • Inheritance in doubled-diploid clementine and comparative study with SDR unreduced gametes of diploid clementine
    Plant Cell Reports, 2016
    Co-Authors: P. Aleza, L. Navarro, J. Juárez, J. Cuenca, P. Ollitrault
    Abstract:

    Key message Tetraploid clementine displays mainly tetrasomic inheritance. Genetic structures of 2n SDR and 2   ×   gametes from DD clementine are complementary and will guides triploids citrus breeding strategies. Abstract Triploid breeding is developed worldwide to create new seedless cultivars. Citrus triploid hybrids can be recovered from 2x × 2x sexual Hybridizations as a consequence of the formation of unreduced gametes (2n), or from 4x × 2x interploid Hybridizations in which tetraploid parents used are most often doubled-diploid (DD). Here we have analyzed the inheritance in doubled-diploid clementine and compared the genetic structures of gametes of DD clementine with SDR unreduced gametes of diploid clementine. Parental heterozygosity restitution (PHR) with DD parents depends on the rate of preferential chromosome pairing and thus the proportion of disomic versus tetrasomic segregations. Doubled-diploid clementine largely exhibited tetrasomic segregation. However, three linkage groups had intermediate segregation and one had a tendency for disomy. Significant doubled reduction rates (DR) rates were observed in six of the nine LGs. Differences of PHR between 2n SDR and 2x DD gametes were highest in the centromeric region and progressively decreased toward the distal regions where they were not significant. Over all markers, PHR was lower (two-thirds) in SDR 2n gametes than in DD-derived diploid gametes. The two strategies appear complementary in terms of genotypic variability. Interploid 4x × 2x Hybridization is potentially more efficient for developing new cultivars that are phenotypically closer to the diploid parent of the DD than sexual Hybridization through SDR 2n gametes. Conversely, 2x × 2x triploidisation has the potential to produce novel products with characteristics for market segmentation strategies.

  • Recovery of citrus cybrid plants with diverse mitochondrial and chloroplastic genome combinations by protoplast fusion followed by in vitro shoot, root, or embryo micrografting
    Plant Cell Tissue and Organ Culture (PCTOC), 2016
    Co-Authors: P. Aleza, A. Garcia-lor, J. Juárez, L. Navarro
    Abstract:

    Somatic embryogenesis and plant regeregeneration are basic processes for the success of citrus somatic Hybridization via protoplast fusion. In many cases, few embryos develop normally and only a small number of plants are recovered. The development of methodologies able to increase the recovery of plants after protoplast fusion experiments it is an important requirement to improve the efficiency of the procedure. Here, plants were regenerated at high efficiency using in vitro micrografting of shoots, roots, and embryos recovered after different somatic Hybridizations. Hybridizations were performed using protoplasts isolated from Chios mandarin callus with protoplasts isolated from Clementine mandarin leaves and from Sanguinelli sweet orange callus. Recovered plants were analyzed with flow cytometry and nuclear simple sequence repeat (SSR), mitochondrial InDel, and chloroplast SSR markers to determine genomic structure. One tetraploid cybrid and numerous diploid cybrids were recovered, and these exhibited a range of mitochondrial and chloroplastic genome combinations.

P. Ollitrault – One of the best experts on this subject based on the ideXlab platform.

  • Inheritance in doubled-diploid clementine and comparative study with SDR unreduced gametes of diploid clementine
    Plant Cell Reports, 2016
    Co-Authors: P. Aleza, L. Navarro, J. Juárez, J. Cuenca, P. Ollitrault
    Abstract:

    Key message Tetraploid clementine displays mainly tetrasomic inheritance. Genetic structures of 2n SDR and 2   ×   gametes from DD clementine are complementary and will guides triploids citrus breeding strategies. Abstract Triploid breeding is developed worldwide to create new seedless cultivars. Citrus triploid hybrids can be recovered from 2x × 2x sexual Hybridizations as a consequence of the formation of unreduced gametes (2n), or from 4x × 2x interploid Hybridizations in which tetraploid parents used are most often doubled-diploid (DD). Here we have analyzed the inheritance in doubled-diploid clementine and compared the genetic structures of gametes of DD clementine with SDR unreduced gametes of diploid clementine. Parental heterozygosity restitution (PHR) with DD parents depends on the rate of preferential chromosome pairing and thus the proportion of disomic versus tetrasomic segregations. Doubled-diploid clementine largely exhibited tetrasomic segregation. However, three linkage groups had intermediate segregation and one had a tendency for disomy. Significant doubled reduction rates (DR) rates were observed in six of the nine LGs. Differences of PHR between 2n SDR and 2x DD gametes were highest in the centromeric region and progressively decreased toward the distal regions where they were not significant. Over all markers, PHR was lower (two-thirds) in SDR 2n gametes than in DD-derived diploid gametes. The two strategies appear complementary in terms of genotypic variability. Interploid 4x × 2x Hybridization is potentially more efficient for developing new cultivars that are phenotypically closer to the diploid parent of the DD than sexual Hybridization through SDR 2n gametes. Conversely, 2x × 2x triploidisation has the potential to produce novel products with characteristics for market segmentation strategies.

  • Somatic Hybridization in citrus: An effective tool to facilitate variety improvement
    In Vitro Cellular & Developmental Biology – Plant, 2000
    Co-Authors: J. W. Grosser, P. Ollitrault, O. Olivares-fuster
    Abstract:

    Citrus somatic Hybridization and cybridization via protoplast fusion has become an integral part of citrus variety improvement programs worldwide. Citrus somatic hybrid plants have been regenerated from more than 200 parental combinations, and several cybrid combinations have also been produced. Applications of somatic Hybridization to citrus scion improvement include the production of quality tetraploid breeding parents that can be used in interploid crosses to generate seedless triploids, and the direct production of triploids by haploid + diploid fusion. Applications of somatic Hybridization to citrus rootstock improvement include the production of allotetraploid hybrids that combine complementary diploid rootstocks, and to combine citrus with sexually incompatible or difficult to hybridize genera that possess traits of interest for germplasm expansion. A few somatic hybrid tetraploid breeding parents have flowered, are fertile, and are being used as pollen parents to generate triploids. Several allotetraploid somatic hybrid rootstocks are performing well in commercial field trials, and show great promise for tree size control. Seed trees of most of these somatic hybrid rootstocks are producing adequate nucellar seed for standard propagation. Somatic Hybridization is expected to have a positive impact on citrus cultivar improvement efforts.

Karl-heinz Schleifer – One of the best experts on this subject based on the ideXlab platform.

  • application of a suite of 16s rrna specific oligonucleotide probes designed to investigate bacteria of the phylum cytophaga flavobacter bacteroides in the natural environment
    Microbiology, 1996
    Co-Authors: Werner Manz, Wolfgang Ludwig, Rudolf Amann, Marc Vancanneyt, Karl-heinz Schleifer
    Abstract:

    We designed a panel of four 16S rRNA-targeted oligonucleotide probes specific for bacteria of the phylum cytophaga-flavobacter-bacteroides (CFB). Probes CF319a and CF319b are targeted to members of the flavobacteriacytophaga group and the genus Porphyromonas, whereas probe BAC303 has a target region characteristic for the genera Prevotella and Bacteroides within the bacteroides group. The probe FFE8b was developed for species-specific Hybridizations with Flavobacterium ferrugineum. All probes were designed by computer-assisted sequence analysis and compared to all currently accessible 16S and 23S rRNA sequences. The oligonucleotides were further evaluated by whole-cell and non-radioactive dot-blot Hybridization against reference strains of the CFB phylum and other major lineages of Bacteria. The newly developed probes were used together with other higher-order probes to analyse the structure and community composition in complex environments. In activated sludge samples, members of the flavobacteriacytophaga group were revealed by in situ Hybridization as important constituents of sludge flocs and characteristic colonizers of filamentous bacteria. By application of fluorescent probe BAC303, members of the genera Bacteroides and Prevotella could be visualized without prior cultivation as an important part of the human faecal microflora.

  • nucleic acid based detection systems for genetically modified bacteria
    Systematic and Applied Microbiology, 1995
    Co-Authors: Wolfgang Ludwig, Elke Brockmann, Claudia Beimfohr, Christian Hertel, Bodil L Jacobsen, Karl-heinz Schleifer
    Abstract:

    Summary Monitoring techniques for genetically modified nucleic acids and organisms were developed and evaluated using modified proteinase genes from lactococci as model sytems. The methods are based on specific nucleic acid probe Hybridizations and on diagnostic DNA in vitro amplifications. The polymerase chain reaction technique (PCR) based approaches as well as the probe Hybridization techniques allow to detect the presence of modified nucleic acids within the sample. However, the genetically modified organisms themselves as well as lateral gene transfer can only be monitored by using the in situ colony Hybridization method. The model sytems were used to analyze mixed cultures, food samples, gut contents, and feces for the presence of introduced genetically modified organisms and the fate of the modified nucleic acids.

Monique Gillis – One of the best experts on this subject based on the ideXlab platform.

  • advantages of multilocus sequence analysis for taxonomic studies a case study using 10 housekeeping genes in the genus ensifer including former sinorhizobium
    International Journal of Systematic and Evolutionary Microbiology, 2008
    Co-Authors: Miet Martens, Monique Gillis, Renata Coopman, Peter Dawyndt, Paul De Vos, Anne Willems
    Abstract:

    There is a need for easy, practical, reliable and robust techniques for the identification and classification of bacterial isolates to the species level as alternatives to 16S rRNA gene sequence analysis and DNA–DNA Hybridization. Here, we demonstrate that multilocus sequence analysis (MLSA) of housekeeping genes is a valuable alternative technique. An MLSA study of 10 housekeeping genes (atpD, dnaK, gap, glnA, gltA, gyrB, pnp, recA, rpoB and thrC) was performed on 34 representatives of the genus Ensifer. Genetic analysis and comparison with 16S and 23S rRNA gene sequences demonstrated clear species boundaries and a higher discrimination potential for all housekeeping genes. Comparison of housekeeping gene sequence data with DNA–DNA reassociation data revealed good correlation at the intraspecies level, but indicated that housekeeping gene sequencing is superior to DNA–DNA Hybridization for the assessment of genetic relatedness between Ensifer species. Our MLSA data, confirmed by DNA–DNA Hybridizations, support the suggestion that Ensifer xinjiangensis is a later heterotypic synonym of Ensifer fredii.

  • in most bradyrhizobium groups sequence comparison of 16s 23s rdna internal transcribed spacer regions corroborates dna dna Hybridizations
    Systematic and Applied Microbiology, 2003
    Co-Authors: Anne Willems, Philippe De Lajudie, Antonio Munive, Monique Gillis
    Abstract:

    Summary In an extension of a previous small-scale test to assess the use of 16S-23S rDNA internal transcribed spacer (ITS) sequences for rapid grouping of bradyrhizobia, we have sequenced the ITS region of 32 isolates of Bradyrhizobium that had previously been studied using AFLP and DNA-DNA Hybridizations. We also included representatives of Afipia and Rhodopseudomonas . Our results indicate that ITS sequences are very diverse among bradyrhizobia. Nevertheless, for most of the bradyrhizobia, the grouping of ITS sequences was in line with AFLP results and DNA-DNA Hybridization data. Strains that have at least 95.5% ITS sequence similarity belong to the same genospecies, i.e. they have more than 60% DNA-DNA Hybridization values. The ITS sequences can therefore provide a relatively fast way to guide strain identification and aid selection of the reference groups that should be included in DNA-DNA Hybridization experiments for precise genotypic identification. The Bradyrhizobium strains isolated from Aeschynomene species showed a much larger diversity in ITS sequences than other bradyrhizobia, possibly as a result of lateral exchange. The above ITS sequence similarity criterion for genospecies therefore does not apply to them, but they can easily be distinguished from other Bradyrhizobium genospecies because they have a distinct tRNA ala gene.

  • dna dna Hybridization study of bradyrhizobium strains
    International Journal of Systematic and Evolutionary Microbiology, 2001
    Co-Authors: Anne Willems, Florence Doignonbourcier, Johan Goris, Renata Coopman, Philippe De Lajudie, Monique Gillis
    Abstract:

    DNA-DNA Hybridizations were performed between Bradyrhizobium strains, isolated mainly from Faidherbia albida and Aeschynomene species, as well as Bradyrhizobium reference strains. Results indicated that the genus Bradyrhizobium consists of at least 11 genospecies, I to XI. The genospecies formed four subgeneric groups that were more closely related to each other (>40% DNA Hybridization) than to other genospecies (<40% DNA Hybridization): (i) genospecies I (Bradyrhizobium japonicum), III (Bradyrhizobium liaoningense), IV and V; (ii) genospecies VI and VIII; (iii) genospecies VII and IX; and (iv) genospecies II (Bradyrhizobium elkanii), X and XI. Photosynthetic Aeschynomene isolates were found to belong to at least two distinct genospecies in one subgeneric group. DNA-DNA Hybridization data are compared with data from amplified fragment length polymorphism analysis and 165-23S rDNA spacer sequence analysis.

Alain C. Frantz – One of the best experts on this subject based on the ideXlab platform.

  • Evidence of hybridisation between the common Indonesian banded pig (Sus scrofa vitattus) and the endangered Java warty pig (Sus verrucosus)
    Conservation Genetics, 2020
    Co-Authors: Frank Drygala, Johanna Rode-margono, Gono Semiadi, Alain C. Frantz
    Abstract:

    Due to hybridisation and breakdown of reproduction barriers the Java warty pig an endangered suid endemic to Java, may be assimilated into the gene pools of the more common Indonesian banded pig and become extinct. Here, we aimed to detect introgressive hybridisation between both suids by microsatellite genotyping warty pigs from two captive populations and from the wild, as well as a banded pig population. While all but one captive individual were genetically pure, we showed, in contrast to a previous survey based on skull measurements, that five wild-born warty pigs in West Java were hybrids. Moreover, we detected four F2 hybrids in the wild warty pig population ( q _ range 0.15–0.99) and one F2 hybrid in the wild banded pig population (q = 0.25), confirming reproductive fertility for F1 hybrids. Our results highlight the potential risk of extinction through Hybridization and genetic swamping of the endangered warty pig.