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Molecular cytogenetic characterization of pre-breeding material produced
with perennial Thinopyrum species in Martonvásár
Gabriella Linc – Gyula Vida – Ottó Veisz – Márta Molnár-Láng
Agricultural Institute, Centre for Agricultural Research, Hungarian Academy of Sciences
Martonvásár 2462, Brunszvik Str.2. Hungary
This research was supported by the Hungarian National Grant (OTKA) nr. 104382 and a Janos Bolyai research fellowship to G.L.
Introduction
Wild relatives of cultivated wheat in the tribe Triticeae represent a rich potential source of
genetic variation for many agriculturally significant characteristics. Perennial species such as wheat
grasses includes diploid and polyploid species, containing genomes that are non-homologous to those
of wheat, are important as tertiary gene pools for wheat improvement. Species belonging to the
Thinopyrum genus are known to possess genes conferring resistance to various diseases and are
capable to produce hybrids with bread wheat.
Materials and methods
• probe labelling by Nick translation using DIG- or Biotin NT-mix and detected with streptavidin- FITC and anti-
digoxigenin-Rhodamine
• FISH and GISH according to Linc et al. 2012.
• rows of varieties were inoculated in development stage 37-39 on the Zadoks scale (Zadoks et al. 1974) using the
uredospore mixture
• the extent of infection at development stage 77-83 was evaluated in terms of severity (according to the modified Cobb
scale) and host response (resistant, moderately resistant, intermediate, moderately susceptible and susceptible; Stubbs et
al. 1986).
Aim
Our main goal is the characterization of pre-breeding material produced previously in Martonvásár
using BE-1 (wheat–Thinopyrum ponticum partial amphiploid) and different wheat genotypes (leaf
rust resistant and susceptible genotypes) using molecular cytogenetic methods.
Results and future prospects
Pre-breeding material developed earlier in Martonvásár were
maintained in nursery and greenhouse (Fig 1). After the 12
generations, new partial amphiploid lines with higher chromosome
number (50-56) were isolated and Thinopyrum chromosomes were
detected by GISH (Fig 2). Several stable pre-breeding line with 42
chromosomes were selected and analyzed by FISH using repetitive
DNA sequences (Fig 3). Chromosome 3B of the LRMAS 10 line showed
polymorphism compared to the 3B FISH chromosome pattern of the
GK Öthalom genotype (Fig 4a, b). Their leaf rust resistance was
evaluated in an artificially inoculated nursery. LRMAS 10 line
produced by BE-1 and GK Öthalom (leaf rust susceptible wheat
genotype) crosses was selected as a leaf rust resistant genotype
after the artificial infection (Fig 5). Further experiments in order to
detect alien DNA in the wheat background by GISH and molecular
marker analysis is in progress.
References
Zadoks JC, Chang TT, Konzak CF (1974) A decimal code for the growth stages of cereals. Weed Res 14, 415-421.
Stubbs RW, Prescott EE, Saari EE, Dubin HJ (1986) Cereal disease methodology manual. CIMMYT, Mexico
Linc G, Sepsi A, Molnár-Láng M (2012) A FISH karyotype to study chromosome polymorphisms for the Elytrigia elongata E genome. Cytogenet. Genome Res.
136:138-144 DOI: 10.1159/000334835
Fig 1. LRMAS 10 line maintained in nursery,Martonvásár.
Pseudoroegneria spicata Triticum aestivum
Fig 2. LRMAS 9 line chromosomes after
GISH. Pseudoroegneria spicata DNA
detected anti-DIG-Rhodamine (red colour),
wheat chromosomes counterstained with
DAPI (blue colour).
Fig 5. The extent of infection 1 week after
the inoculation. a; BE1, b; GK Öthalom,
c; LRMAS 10.
a b c
Fig 3. FISH chromosome pattern of the LRMAS 10 line.
pSc119.2 Afa family
a b
Fig 4. FISH pattern of 3B chromosome of the
genotypes a; GK Öthalom and b; LRMAS 10 using
pSc119.2 (green) and Afa family (red) repetitiv DNA
sequences.