Bibliothek

feed icon rss

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
  • 1
    Digitale Medien
    Digitale Medien
    Springer
    Theoretical and applied genetics 70 (1985), S. 128-132 
    ISSN: 1432-2242
    Schlagwort(e): Anther culture ; Androgenesis ; Haploid production ; Pretreatment ; Tobacco
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary A total of six genotypes of Nicotiana rustica comprising the two F1's (V2 × V12 and V1 × V5) and their parents were evaluated for their efficiency in haploid production. Excised immature flower buds with pollen at late uninucleate to early binucleate stage were pretreated for 21 days at 5 ° or 7 °C, or for 15 days at 9 °C before culturing on Nitsch's medium+ 0.1 mg/l NAA. The effects of genotype, pretreatment and their interaction were tested on anther response, anther productivity and days to first plantlet formation. Highly significant genotype X pretreatment interaction and differences between genotypes were observed for all three characters. Significant differences between pretreatments were observed for anther productivity only. The performance of V12 both in respect of anther productivity and response was highest whereas that of V5 was the lowest. Analysis of variance showed that a simple additive genetic model was not adequate to explain the above variation due to significant additive genetic and dominance interactions with the pretreatment.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 2
    Digitale Medien
    Digitale Medien
    Springer
    World journal of microbiology and biotechnology 10 (1994), S. 568-571 
    ISSN: 1573-0972
    Schlagwort(e): Cholera toxin ; non-culturable ; PCR ; Vibrio cholerae
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: Abstract Cholera enterotoxin is a major antigenic determinant for virulence of Vibrio cholerae O1 which can enter into a viable but non-culturable (N-C) state, not detectable by conventional culture methods, yet remain capable of producing enterotoxin and potentially pathogenic. PCR was applied in the current study to detect the chilera toxin (ctx) gene of N-C cells, thus eliminating the necessity of culture. Sets of oligonucleotide primers were designed, based on the ctxAB operon of V. cholerae O1, to detect the presence of the ctx gene. DNA from both culturable and N-C cells of V. cholerae O1 was amplified by PCR using sets of primers flanking 302-, 564- and 777-bp fragments of the ctx gene. The PCR method employed was capable of detecting the ctx gene in N-C V. cholerae in aquatic microcosms and in diarrheal stool samples from three patients who had distinct clinical symptoms of cholera but were culture-negative for V. cholerae O1 and non-O1 and enterotoxigenic Escherichia coli. Forty cycles of a two-step reaction (30 s each at 94 and 60°C) were optimal and more time efficient than a three-step PCR described previously. The procedure, from the point of heating microcosms or broth culture samples to observation on gels, requires 〈 4 h to complete.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 3
    ISSN: 1573-0972
    Schlagwort(e): Cholera toxin ; PCR ; Vibrio cholerae non-O1 ; V. cholerae O1 ; V. cholerae O139 ; Zonula occludens toxin
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Werkstoffwissenschaften, Fertigungsverfahren, Fertigung
    Notizen: Abstract Vibrio cholerae O1 and V. cholerae non-O1 strains isolated from environmental samples collected in São Paulo, Brazil, during cholera epidemics and pre-epidemic periods were examined for the presence of toxin genes. V. cholerae O1 strains isolated from clinical samples in Peru and Mexico, and V. cholerae O139 strains from India were also examined for the presence of ctx (cholera toxin gene) and zot (zonula occludens toxin gene) by polymerase chain reaction (PCR). A modified DNA-extraction method applied in this study yielded satisfactory recovery of genomic DNA from vibrios. Results showed that strains of V. cholerae O1 isolated during the preepidemic period were ctx -/zot - whereas strains isolated during the epidemic were ctx +/zot +. All V. cholerae non-O1 strains tested in the study were ctx -/zot -, whereas all V. cholerae O139 strains were ctx +/zot +. Rapid detection of the virulence genes (ctx and zot) can be achieved by PCR and this can serve as an important tool in the epidemiology and surveillance of V. cholerae.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 4
    Digitale Medien
    Digitale Medien
    Springer
    Theoretical and applied genetics 69 (1984), S. 199-204 
    ISSN: 1432-2242
    Schlagwort(e): Nicotiana rustica ; Temperature-pretreatment ; Anther culture ; Haploids ; Dihaploids
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Summary The efficiency of dihaploid production from anther culture in N. rustica has been improved by studying the effects of pretreatment temperature, pretreatment duration and initial anther stage on anther response, anther productivity and time to first plantlet production. Pretreatment was most effective on anthers at or around the stage of pollen mitosis. Pollen mitosis stage anthers pretreated at 9 °C for 15 days gave the best results. Both spontaneous and induced dihaploids were obtained. Small plantlets treated with 0.4% colchicine and 2% DMS solution for 5 h produced the maximum number of dihaploids (more than 50%). These considerable improvements in the efficiency of the techniques have made dihaploidy an attractive method for producing inbred lines in N. rustica. This will permit a large scale comparison of dihaploids with more conventional methods of inbreeding such as single seed descent and pedigree breeding.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...