Towards the saturation of the pepper linkage map by alignment of three intraspecific maps including known-function genes

Abstract

Three populations composed of a total of 215 doubled haploid lines and 151 F2 individuals were used to design an intraspecific consensus map of pepper (Capsicum annuum L.). The individual maps varied from 685 to 1668 cM with 16 to 20 linkage groups (LGs). The alignment of the three individual maps permitted the arrangement of 12 consensus major linkage groups corresponding to the basic chromosome number of pepper and displaying a complex correspondence with the tomato map. The consensus map contained 100 known-function gene markers and 5 loci of agronomic interest (the disease-resistance loci L, pvr2, and Pvr4; the C locus, which determines capsaicin content; and the up locus, controlling the erect habit of the fruits). The locations of three other disease-resistance loci (Tsw, Me3, and Bs3) and the y locus, which determines the yellow fruit colour, were also found on this consensus map thanks to linked markers. Here we report on the first functional detailed map in pepper. The use of candidate gene sequences as genetic markers allowed us to localize four clusters of disease-resistance gene analogues and to establish syntenic relationships with other species.

QTL Analysis for Resistance to Ralstonia solanacearum in Capsicum Accession ‘LS2341’

“…The present linkage map covered 974 cM of the pepper genome, and the coverage was somewhat shorter than in the published pepper maps (Lefebvre et al, 2002); however, the map distance calculated by JoinMap is always shorter than that by Mapmaker (Bradeen et al, 2001); therefore, the present map is thought to cover most of the pepper genome. Nevertheless, QTL other than that in LG11 was not found in this study, indicating that the present QTL in LG11 might be the most effective QTL in this resistant accession, 'LS2341'.…”

Mapping of the ms8 male sterility gene in sweet pepper (Capsicum annuum L.) on the chromosome P4 using PCR-based markers useful for breeding programmes

“…NuMex RNaky indicate that the ms8 locus is located on the lower arm of the pepper chromosome P4. In addition to the ms8 locus, a number of other important traits of pepper were mapped to the P4 chromosome: the pvr2 locus for PVY resistance (Caranta et al 1997;Lefebvre et al 2002), the C2 locus for fruit color (Thorup et al 2000), QTLs for fruit weight and shape (Barchi et al 2009;Zygier et al 2005), and QTL for Phytophthora capsici resistance (Thabuis et al 2004). It has to be considered in the breeding programmes aimed to introgress ms8 gene into the different breeding lines.…”

“…Middle the ms8 linkage group. Right simplified P4 linkage group derived from the genetic map of Perennial x Yolo Wonder, published earlier by Lefebvre et al (2002), with SCAR_V01 and SCAR_N2 markers mapped. Markers common for particular linkage groups were connected with solid lines.…”

“…Male fertility in F 3 families was evaluated visually by scoring flower morphology and the segregation ratios were calculated. A mapping reference population of pepper Perennial x Yolo Wonder, consisting of 114 DH lines (Lefebvre et al 2002) was used to map the SCAR markers N2 and V01 and to determine on which chromosome (linkage group) the ms8 locus maps.…”

Resistance of Chili Pepper Cultivars to Isolates of Phytophthora capsici

“…고추 역병에 대한 유전자원들의 저항성에 관한 연구가 모두 이해된 것은 아니다. 처음에는 독립적으 로 작용하는 2개의 우성유전자에 의해 (Polach and Webster, 1972;Smith et al, 1967) 혹은 modifier와 함께 단일 우성 유전자 (Barksdale et al, 1984)가 저항성을 나타낸다고 하였 으나, 최근에는 고추의 역병 저항성을 질적 저항성보다는 chromosome 4, 5, 6, 11 및 12에 존재하는 6개 영역이 저항 성을 책임지는 QTL 저항성으로 인식하고 있다 (Lefebvre and Palloix, 1996;Lefebvre et al, 2002;Pflieger et al, 2001;Thabuis et al, 2003Thabuis et al, , 2004. 또한 고추의 역병 저항성은 접 종원 농도와 배양시간에 따라 영향을 받으며, 또 고추의 생 육시기가 증가할수록 저항성 발현이 뚜렷하게 증가한다고 알려져 있어 이를 뒷받침한다 (Barksdale et al, 1984;Hwang, 2002;Kim et al, 1989).…”