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
Filter
  • drought intensity index  (1)
  • epistatic resistance genes  (1)
  • 1
    ISSN: 1573-5060
    Schlagwort(e): bean common mosaic virus (BCMV) ; bean common mosaic necrosis virus(BCMNV) ; epistatic resistance genes ; gene pyramiding ; Phaseolus vulgaris ; SCAR marker
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract Pyramiding epistatic resistance genes to improve long term disease resistance has challenged plant breeders. Indirect selection using tightly linked markers will often facilitate the breeding of desired epistatic resistance gene combinations. In common bean, the most effective strategy for broad spectrum control of the bean common mosaic virus disease is to combine I, bc-u, bc-1 2, bc-2 2, and bc-3 genes. We describe the use of near-isogenic lines and bulked segregant analysis to identify a marker tightly linked with the bc-1 2 gene. The recessive bc-1 2 gene conditions resistance to specific strains of bean common mosaic virus and bean common mosaic necrosis virus and is masked by the bc-2 2 and bc-3 genes. We identified a RAPD marker completely linked (0 recombinants) with bc-1 2, based on 72 F3 progeny generated from a cross between the contrasting near isogenic lines (I + bc-1/I + bc-1 2). Segregation in this I gene background revealed that bc-1 2 was dominant to bc-1 in conferring resistance to top necrosis in the allelic series Bc-1 〉 bc-1 2 〉 bc-1. To facilitate marker-assisted selection of bc-1 2 across breeding programs, the RAPD was converted to a SCAR marker, designated SBD51300. Tight linkage (0 recombinants) was confirmed in a second population of 58 F2 progeny co-segregating for SBD51300 and bc-1 2 gene from a different source. Based on a survey of 130 genotypes, the SCAR will be useful for MAS of bc-1 2 in most beans of Middle American origin and snap beans, but will have very limited utility in the case of kidney and cranberry beans. The SBD51300 marker mapped on linkage group B3, revealing independence of bc-1 2 from the I gene on B2 and bc-3 gene on B6, which supports the opportunity to readily combine genes for broad spectrum and pyramided resistance to bean common mosaic potyviruses in a single bean cultivar.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 2
    Digitale Medien
    Digitale Medien
    Springer
    Euphytica 99 (1998), S. 127-136 
    ISSN: 1573-5060
    Schlagwort(e): drought ; drought intensity index ; drought susceptibility index ; geometric mean ; yield ; Phaseolus vulgaris L.
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Land- und Forstwirtschaft, Gartenbau, Fischereiwirtschaft, Hauswirtschaft
    Notizen: Abstract Common bean (Phaseolus vulgaris L.) is grown in regions where water deficits during reproductive development significantly reduce yield. The purpose of this study was to evaluate the association of specific phenological and physiological traits with drought resistance in common bean. Five genotypes were grown under and near a rain shelter in 1988, and an additional 16 progeny lines were included in 1990. Drought stress determined by the drought intensity index was severe (0.78) in 1988 and more moderate (0.63) in 1990. Water stress reduced the expression of most traits with the exception of days to flower and leaf moisture retention capacity. Seed yield among genotypes was reduced from 22 to 71% due to drought. Yield under stress was correlated with yield under nonstress in 1990 and negatively correlated with the drought susceptibility index in 1988. Yield components which exhibited the largest differential genotypic responses to stress were pod and seed number, whereas seed size was more stable. Genotypic variation was detected in all the partitioning indexes, chiefly harvest index and relative sink strength, and the heritability estimates for these traits were high. The limited genetic variability observed among water relations traits and their role in water conservation would restrict their potential use in the selection for drought resistance in common bean. The differential correlations between phenological, biomass and partitioning traits and the indexes for yield and drought susceptibility would suggest that the most effective approach in breeding for drought resistance in common bean would be based first on selection for high geometric yield followed by selection among the high-yielding individuals for low to moderate levels of the drought susceptibility index.
    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...