An Extended Linkage Map of Sugar Beet (Beta vulgaris L.) Including Nine Putative Lethal Genes and the Restorer Gene X

Abstract

An extended genetic map of sugar beet {Beta vulgaris L.) is presented encompassing 177 segregating markers (2 morphological traits, 7 isozymes, and 168 RFLP markers) on 9 linkage groups. The linkage map comprises 1057.3 cM equivalent to an average genetic spacing of 6.0 cM/marker. The length of individual linkage groups varies between 80.7 (group VIII) and 167.4 cM (group VII). The number of markers per linkage group ranges between 13 and 24. No indication of duplicate regions was found, confirming the true diploid nature of B. vulgaris. Twenty-six markers (15 %) deviated significantly (a = 0.01) from the expected segregation ratio. This distorted segregation was probably caused by Hnkage with lethal genes. Four such genes (designated Let lb. Let 5b, Let 6b, Let 8) could be located at discrete positions due to their absolute Hnkage to skewed RFLP markers. The restorer gene X has been located terminally on linkage group III, 9.6 cM distant from RFLP marker pKP1238.

A first linkage map of olive (Olea europaea L.) cultivars using RAPD, AFLP, RFLP and SSR markers

“…Distorted segregation ratios, which occur in several annual and perennial plants, may be attributed to the presence of incompatibility or lethal alleles, as in sugar beet (Pilien et al 1993), or may result from competition among gametes or from abortion of the gamete or zygote, such as in Aegilops (Faris et al 1998). Nevertheless, the inclusion of skewed markers in the olive maps did not affect the linkage arrangement, and they were distributed along the linkage groups (Figs.…”

The distribution of normal and male-sterile cytoplasms in Chinese sugar-beet germplasm

“…The Owen cytoplasm is known to be associated with the gain of a HindIII restriction site in the petGpsbE intergenic spacer within the chloroplast genome (Ran and Michaelis 1995;Y. Yanai et al Research Faculty of Agriculture, Hokkaido University, DDBJ/ EMPL/GenBank accession number AB242560; Dufay et al 2008).…”

Genome Analysis: Mapping in Sugar Beet

“…Location of genes for Mendelian traits and quantitatively inherited characters (QTL) on the nine chromosomes of sugar beet. The chromosomes were designated as suggested by Butterfass (1963) and PsbO, cTRF, PsaL, PsbR, PetH, PsbP, PsaE, PsbQ, PsaH, PetC (Pillen et al 1996) d Butterfass (1963) e Keller (1936); Owen et al (1940); Owen and Ryser (1942) f Early bolting B (Boudry et al 1994) g Root color Y, curly top resistance C, cited from (Wagner et al 1992) h Stem fasciation Fas, restoration of male fertility Z and X, and more isozyme loci (Wagner et al 1992) i Nematode resistance gene Nema (Uphoff and Wricke 1995) j Pillen et al (1993) k Resistance to rhizomania, Rr1, monogerm character M (Barzen et al 1995) l Skdh2 might be linked with a restorer gene, perhaps X (Abe et al 1993) m Z might be linked with M (Roundy and Theurer 1974) n Late bolting, Nb, sugar content, Sc (Savitsky 1958) o Laporte et al (1998) Weber et al (2000) t Setiawan et al (2000) u Schäfer-Pregl et al (1999) v Scholten et al (1999) w Hjerdin-Panagopoulos et al (2002) x Schneider et al (2002) cence were processed, resulting in the identification of 30,444 clusters (Herwig et al 2002). After sequencing 10,961 clones, 9745 different cDNAs were identified.…”

“…Linkage maps of sugar beet. The map of Schumacher et al (1997) combines markers from different maps previously published by Schondelmaier et al (1996) and Barzen et al (1995) Size Pillen et al (1993); Schondelmaier et al (1995Schondelmaier et al ( , 1996 49 248 Nema nematode resistance sponding loci, while Rae et al (2000) reported 23 markers mapped to the nine linkage groups of beet previously established by Barnes et al (1996). Single nucleotide polymorphisms (SNP) are highly abundant in the genome of sugar beet.…”

“…Those maps were extended by molecular markers and later the linkage groups were assigned to the nine chromosomes of beet (Table 1). The RFLP map of Pillen et al (1992Pillen et al ( , 1993 and Schondelmaier et al (1995) contained the gene for red hypocotyl color R, the restorer gene X, the gene for early bolting B and the Hs1 pro-1 gene for nematode resistance together with six isozyme markers previously mapped by Wagner et al (1992). Later, this map was extended by amplified fragment length polymorphisms (AFLPs; Schondelmaier et al 1996).…”