SSR markers closely associated with genes for resistance to root-knot nematode on chromosomes 11 and 14 of Upland cotton

Abstract

Molecular markers closely linked to genes that confer a high level of resistance to root-knot nematode (RKN) [Meloidogyne incognita (Kofoid & White) Chitwood] in cotton (Gossypium hirsutum L.) germplasm derived from Auburn 623 RNR would greatly facilitate cotton breeding programs. Our objectives were to identify simple sequence repeat (SSR) markers linked to RKN resistance quantitative trait loci (QTL) and map these markers to specific chromosomes. We developed three recombinant inbred line (RIL) populations by single seed descent from the crosses of RKN-resistant parents M-240 RNR (M240), developed from the Auburn 623 RNR source, moderately resistant Clevewilt 6 (CLW6), one of the parents of Auburn 623 RNR, and susceptible parent Stoneville 213 (ST213). These crosses were CLW6 × ST213, M240 × CLW6, and M240 × ST213. RILs from these populations were grown under greenhouse conditions, inoculated with RKN eggs, scored for root gall index, eggs plant(-1), and eggs g(-1) root. Plants were also genotyped with SSR markers. Results indicated that a minimum of two major genes were involved in the RKN resistance of M240. One gene was localized to chromosome 11 and linked to the marker CIR 316-201. This CIR 316-201 allele was also present in CLW6 but not in Mexico Wild (MW) (PI593649), both of which are parents of Auburn 623 RNR. A second RKN resistance gene was localized to the short arm of chromosome 14 and was linked to the SSR markers BNL3545-118 and BNL3661-185. These two marker alleles were not present in CLW6 but were present in MW. Our data also suggest that the chromosome 11 resistance QTL primarily affects root galling while the QTL on chromosome 14 mediates reduced RKN egg production. The SSRs identified in this study should be useful to select plants with high levels of RKN resistance in segregating populations derived from Auburn 623 RNR.

Genetic diversity of Gossypium barbadense from the central Brazilian Amazon

“…DC20027 is linked to the Rghv1 gene that confers resistance to cotton blue disease ; CIR246, to the B12 gene, which confers resistance to angular leaf spot ; BNL3279, to one locus confering resistance to reniform nematode (Dighe et al 2009); and CIR316M (Shen et al 2006) and BNL3661 (Guitiérrez et al 2010), which are associated with two different loci that control root-knot nematode tolerance. The allele reported in G. hirsutum linked to resistance to root-knot nematode, BNL3661-185 bp, is present in 40% of the G. barbadense Amazon accessions (Table 2).…”

Optimal use of SSR markers for varietal identification of upland cotton

“…Out of these 17 markers, the following 12 were selected based on the polymorphism screening performed in the present study, considering the highest PIC and DP values: BNL2499, BNL3482, CIR030, CIR055, CIR081, CIR099, CIR165, CIR170, CIR249, CIR373, JESPR153, and JESPR292. Moreover, five SSRs evaluated in previous studies were also included in the present study due to shared specific interests: BNL3661, for resistance to the root-knot nematode, Meloidogyne incognita (Gutiérrez et al, 2010); CIR316, for resistance to M. incognita (Ulloa et al, 2010); JESPR101, related to four production or fiber traits (Zhang et al, 2013); JESPR110, related to fiber traits (Wang et al, 2011); and JESPR304, for resistance to Fusarium oxysporum wilt (Wang et al, 2009). Considering that four primer pairs (BNL3661, CIR165, CIR316, and JESPR101) amplified two distinct loci each in the collection of 96 genotypes, 21 loci were produced for varietal identification, i.e., two more than recommended for the collection of 20 genotypes.…”

Reproduction of Meloidogyne incognita Race 3 on Flue-cured Tobacco Homozygous for Rk1 and/or Rk2 Resistance Genes

“…Two quantitative trait loci (QTLs) recently discovered in cotton each confer only moderate resistance to M. incognita when present alone, but when present together confer near immunity (Guti errez et al, 2010;He et al, 2014;Batista da Silva et al, 2015). Both QTLs reduced nematode egg production, but qMi-C11 reduced galling, while qMi114 did not (He et al, 2014).…”