Molecular tagging of a senescence gene by introgression mapping of a stay-green mutation from Festuca pratensis.
* Intergeneric hybrids between Lolium multiflorum and Festuca pratensis (Lm/Fp) and their derivatives exhibit a unique combination of genetic and cytogenetic characteristics: chromosomes undergo a high frequency of homoeologous recombination at meiosis; the chromosomes of the two species can easily be discriminated by genomic in situ hybridization (GISH); recombination occurs along the entire length of homoeologous bivalents; a high frequency of marker polymorphism is observed between the two species. * This combination of characters has been used to transfer and isolate a F. pratensis chromosome segment carrying a mutant 'stay-green' gene conferring a disrupted leaf senescence phenotype into L. multiflorum. * The genetic location within the introgressed F. pratensis segment of the senescence gene has been mapped using amplified fragment length polymorphisms (AFLPs), and F. pratensis-specific AFLP markers closely flanking the green gene have been cloned. * The use of these cloned sequences as markers for the stay-green locus in marker-assisted selection programmes has been tested. The potential application of Lm/Fp introgressions as a tool for the map-based cloning of introgressed Fp genes is discussed.
Moore
B J
BJ
Molecular and Applied Genetics Team, Institute of Grassland and Environmental Research, Plas Gogerddan, Aberystwyth, SY23 3EB, UK.
Donnison
I S
IS
Harper
J A
JA
Armstead
I P
IP
King
J
J
Thomas
H
H
Jones
R N
RN
Jones
T H
TH
Thomas
H M
HM
Morgan
W G
WG
Thomas
A
A
Ougham
H J
HJ
Huang
L
L
Fentem
T
T
Roberts
L A
LA
King
I P
IP
D002874:Chromosome Mapping; D032461:Chromosomes, Plant; D003433:Crosses, Genetic; D031751:Festuca / Q000235:genetics* / Q000502:physiology; D017343:Genes, Plant; D008040:Genetic Linkage; D008129:Lolium / Q000235:genetics; D009154:Mutation; D021141:Nucleic Acid Amplification Techniques; D010641:Phenotype; D011110:Polymorphism, Genetic