Construction of a genetic map based on high-throughput SNP genotyping and genetic mapping of a TuMV resistance locus in Brassica rapa

ABSTRACT The organization of the α- and β-tubulin gene families in Physarum was investigated by Mendelian analysis. Restriction endonuclease-generated DNA fragments homologous to α- and β-tubulin show length polymorphisms that can be used as markers for genetic mapping. Analysis of meiotic assortment among progeny of heterozygotes allowed α- and β-tubulin sequence loci to be defined. There are four unlinked α-tubulin sequence loci (altA, altB, altC and altD) and at least three unlinked β-tubulin sequence loci (betA, betB and betC). The α-tubulin loci are not linked to the β-tubulin loci. —Segregation of tubulin sequence loci with respect to ben mutations that confer resistance to antitubulin benzimidazole drugs was used to investigate whether any members of the α- or β-tubulin gene families are allelic to ben loci. The β-tubulin sequence locus betB is allelic to the resistance locus benD, the betA locus is probably allelic to benA and the α-tubulin sequence locus altC may be allelic to benC. The molecular implications of benzimidazole resistance phenotypes when only one of the expressed β-tubulin gene family members mutates to drug resistance are discussed in relation to tubulin function.

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Identification of QTLs for Stripe Rust Resistance in a Recombinant Inbred Line Population

International Journal of Molecular Sciences ◽

10.3390/ijms20143410 ◽

2019 ◽

Vol 20 (14) ◽

pp. 3410 ◽

Cited By ~ 6

Author(s):

Manyu Yang ◽

Guangrong Li ◽

Hongshen Wan ◽

Liping Li ◽

Jun Li ◽

...

Keyword(s):

Genetic Map ◽

Stripe Rust ◽

Resistance Genes ◽

Phenotypic Variation ◽

Recombinant Inbred ◽

Rust Resistance ◽

High Density ◽

Genetic Maps ◽

Stripe Rust Resistance ◽

Resistance Locus

Stripe rust, caused by Puccinia striiformis f. sp. tritici (Pst), is one of the most devastating fungal diseases of wheat worldwide. It is essential to discover more sources of stripe rust resistance genes for wheat breeding programs. Specific locus amplified fragment sequencing (SLAF-seq) is a powerful tool for the construction of high-density genetic maps. In this study, a set of 200 recombinant inbred lines (RILs) derived from a cross between wheat cultivars Chuanmai 42 (CH42) and Chuanmai 55 (CH55) was used to construct a high-density genetic map and to identify quantitative trait loci (QTLs) for stripe rust resistance using SLAF-seq technology. A genetic map of 2828.51 cM, including 21 linkage groups, contained 6732 single nucleotide polymorphism markers (SNP). Resistance QTLs were identified on chromosomes 1B, 2A, and 7B; Qyr.saas-7B was derived from CH42, whereas Qyr.saas-1B and Qyr.saas-2A were from CH55. The physical location of Qyr.saas-1B, which explained 6.24–34.22% of the phenotypic variation, overlapped with the resistance gene Yr29. Qyr.saas-7B accounted for up to 20.64% of the phenotypic variation. Qyr.saas-2A, a minor QTL, was found to be a likely new stripe rust resistance locus. A significant additive effect was observed when all three QTLs were combined. The combined resistance genes could be of value in breeding wheat for stripe rust resistance.

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