A Database for Triticeae and Avena
Coordinator’s report: Chromosome 2H (2)
of Plant Sciences
Dakota State University
ND 58105, U.S.A.
Hard-copy edition pages 13 - 21.
Marquez-Cedillo et al., 2001
published a more complete report on the analysis of agronomic traits in a
doubled-haploid population from a cross between the two-rowed cv. Harrington
and the six-rowed cv. Morex. The vrs1
(six-rowed spike 1) locus was associated with QTL effects for yield, kernel
plumpness, test weight, and plant height across most test environments. A
region of chromosome 2H proximal from the vrs1
locus was associated with early heading in all eight environments tested.
Schmierer et al., 2001 used a
molecular marker-assisted backcross breeding scheme to demonstrate that
molecular markers near QTLs for yield can be used to identify high yielding
selections from crosses between the high yielding cv. Baronesse and the malting
barley cv. Harrington. Based on studies in the BC2 generation, two
regions in chromosome 2HL and one region in chromosome 3HL were reported to
contain potential QTLs for high yield. Studies on the next backcross generation
further localized the yield QTLs. The QTL in 3HL was estimated to be between
markers MWG571A and MWG961 in Bins 3H-09 and 3H-12, respectively. (See http://barleygenomics.wsu.edu for the latest
barley Bin maps.) The two critical regions in 2HL were between Bmy2 and MWG699 (Bins 2H-07 and 2H-10)
and between ABG072 and ksuD22 (Bins 2H-11 and 2H-12). Since Baronesse has the Vrs1.t (deficiens) allele at the vrs1 locus, which is located in Bin
2H-10, spike type might be useful as visual marker to identify segregates
having as least one QTL for high yield.
Kolb et al., 2001 and Rudd et al., 2001 summarized recent mapping
and breeding studies on resistant to Fusarium head blight (FHB) in barley and
wheat. They reported that QTLs for FHB resistance were identified frequently in
barley chromosome 2H. The critical region of chromosome 2H probably includes
the vrs1 locus and the QTL for early
maturity reported by Marquez-Cedillo et
al., 2001. The early heading QTL is likely the same dominant, photoperiod
sensitive gene identified by Tohno-oka et
al., 2000 in Bin 2H-08 of Morex. The early maturity allele in Morex was
tentatively named Eam6.h
Costa et al., 2001 mapped 12
morphological markers using molecular markers and the doubled-haploid
population named the Oregon Wolfe Barleys. The loci vrs1, wst7 (white streak
7), and Zeo1 (zeocriton 1) were
placed in chromosome 2HL in Bins 2H-10, 2H-15, and 2H-14, respectively. The
relative positions of these morphological markers are similar to those reported
based on studies using only morphological markers (Franckowiak, 1997).
In their study of doubled-haploid lines from a ‘Leger’/CIho 9831 cross,
Frégeau-Reid et al., 2001 found that
the vrs1 region of chromosome 2H has
a major effect on feed quality parameters. Although they used the Vrs1.t (deficiens) allele instead of the
Vrs1.b allele, they observed changes in the
chemical other crosses between two- and six-rowed cultivars. Frégeau-Reid et al., 2001 also studied the effects of
the Pre2 (red lemma and pericarp 2)
gene on grain quality. The higher protein, low starch, and higher beta-glucan
of purple seeded lines was composition similar to those reported for attributed
to linkage between the Pre2 and vrs1 loci, a distance of about 11 cM.
Frégeau-Reid et al., 1996 determined
in a previous study of the same material that the deficiens lines produce
larger, rounder seeds than six-rowed lines.
Castiglioni et al. 1998
demonstrated procedures for mapping morphological mutants using AFLP markers
and placed branched spike mutant (brc-5)
in chromosome 2HS about 2.5 cM from AFLP marker E3636-2. This marker is
proximal from molecular marker CDO665A in Bin 2H-05. The brc-5 mutant causes rachillas in the basal part of the spike
elongate to form rachis-like branches or a second-order ramification of the
Pozzi et al., 2000 using AFLP
markers and the map published by Castiglioni et al., 1998 mapped several calcaroides (cal) mutants and a leafy lemma (lel1)
mutant. In the calcaroides mutants, lemma appendages or modifications are situated
somewhat below the top of the lemma. Only one of the five cal loci was placed in chromosome 2H. The cal-a locus is in chromosome 2HS distal from molecular marker
CDO057A and probably near Bin 2H-01. Since the sbk (subjacent hood) gene in chromosome 2HS is the only previously
mapped calcaroides-like mutant, Pozzi et
al., 2000 assumed that cal-a and sbk are alleles. This information
provides a much better position estimate for the sbk locus than previous linkage studies (Franckowiak, 1997).
Scheurer et al., 2001 reported
further on resistance to barley yellow dwarf virus strain BYDV-PAV and provided
molecular mapping data that indicate two QTLs are associated with plant growth
after infection. The main QTL from ‘Post’ is located near molecular marker HVCSG
in Bin 2H-13 of chromosome 2H. The QTL from ‘Vixen’ is in chromosome 3HL and
was identified as the Ryd2 (reaction
to BYDV 2) gene.
Castiglioni, P., C. Pozzi, M. Heun, V. Terzi, K.J.
Müller, W. Rohde, and F. Salamini. 1998. An AFLP-based procedure for the
efficient mapping of mutations and DNA probes in barley. Genetics
Costa, J.M., A. Corey, P.M. Hayes, C. Jobet, A.
Kleinhofs, A. Kopisch-Obusch, S.F. Kramer, D. Kudrna, M. Li, O. Riera-Lizarazu,
K. Sato, P. Szucs, T. Toojinda, M.I. Vales, and R.I. Wolfe. 2001. Molecular
mapping of the Oregon Wolfe Barleys: a phenotypically polymorphic
doubled-haploid population. Theor. Appl. Genet. 103:415-421.
Franckowiak, J.D. 1997. Revised
linkage maps for morphological markers in barley, Hordeum vulgare. BGN 26:9-21.
Franckowiak, J.D. 2001. Coordinator’s
report: Chromosome 2H (2). BGN 31:45-51. http://wheat.pw.usda.gov/ggpages/bgn/31/ul1txt.htm#2H.
Frégeau-Reid, J., T.M. Choo, P. Jui, and K.M. Ho.
1996. Inheritance of kernel size and shape of barley. SABRAO J. 28:47-55.
Frégeau-Reid, J., T.M. Choo, K.M. Ho, R.A. Martin,
and T. Konishi. 2001. Comparison of two-row and six-row barley for
chemical composition using doubled-haploid lines. Crop Sci. 41:1737-1743.
Kolb, F.L., G-H. Bai, G.J. Muehlbauer, J.A.
Anderson, K.P. Smith, and G. Fedak. 2001. Symposium on genetic solutions
to Fusarium head blight in wheat and barley: Challenges, opportunities, and
imperatives. Crop Sci. 41:611-619.
Marquez-Cedillo, L.A., P.M. Hayes, A. Kleinhofs,
W.G. Legge, B.G. Rossnagel, K. Sato, S.E. Ullrich, and D. M. Wesenberg. 2001. QTL analysis
of agronomic traits in barley based on the doubled haploid progeny of two elite
North American varieties representing different germplasm groups. Theor. Appl.
Pozzi, C., P. Faccioli, V. Terzi, A.M. Stanca, S.
Cerioli, P. Castiglioni, R. Fink, R. Capone, K.J. Müller, G. Bossinger, W.
Rohde, and F. Salamini. 2000. Genetics of mutations affecting the development of
a barley floral bract. Genetics 154:1335-1346.
Rudd, J.C., R.D. Horsley, A.E. McKendry, and E.M.
Elias. 2001. Host plant resistance genes for Fusarium head blight: Sources,
mechanisms, and utility in conventional breeding systems. Crop Sci. 41:620-627.
Scheurer, K.S., W. Friedt, W. Huth, R. Waugh, and
F. Ordon. 2001. QTL analysis of tolerance to a German strain of
BYDV-PAV in barley (Hordeum vulgare L.). Theor. Appl. Genet. 103:1074-1083.
Schmierer, D., N. Kandemir, D. Kudrna, D.
Wesenberg, S. Ullrich, and A. Kleinhofs. 2001. Molecular
marker-assisted selection for increased yield of traditional malting barley
cultivars. BGN 31:6-11. http://wheat.pw.usda.gov/ggpages/bgn/31/schmierer.htm.
Tohno-oka, T., M. Ishit, R. Kanatani, H. Takahashi,
and K. Takeda. 2000. Genetic analysis of photoperiodic response of
barley in different daylength conditions. p. 239-241. In S. Logue (ed.), Barley Genetics VIII. Proc. Eighth Int. Barley
Genet. Symp., Departm. of Plant Science, Waite Campus, Adelaide University,
Glen Osmond, South Australia 5064. Vol. 3:239-241.