Molecular physiology and breeding at the crossroads of cold hardiness improvement
Castonguay Yves
Molecular physiology and breeding at the crossroads of cold hardiness improvement - Physiologia Plantarum 2013 - 64-74
Alfalfa (Medicago sativa L) is a major forage legume grown extensively worldwide with important agronomic and environmental attributes. Insufficient cold hardiness is a major impediment to its reliable production in northern climates. Improvement of freezing tolerance using conventional breeding approaches is slowed by the quantitative nature of inheritance and strong interactions with the environment. The development of gene-based markers would facilitate the identification of genotypes with superior stress tolerance. Successive cycles of recurrent selection were applied using an indoor screening method to develop populations with significantly higher tolerance to freezing (TF). Bulk segregant analysis of heterogeneous TF populations identified DNA variations that are progressively enriched in frequency in response to selection. Polymorphisms resulting from intragenic variations within a dehydrin gene were identified and could potentially lead to the development of robust selection tools. Our results illustrate the benefits of feedback interactions between germplasm development programs and molecular physiology for a deeper understanding of the molecular and genetic bases of cold hardiness.
AFLP
Amplified fragment length polymorphism
BSA
Bulk segregant analysis
CBF
CNV
cold-regulated
Copy number variation
COR
c-repeat binding factor
c-repeat/dehydration responsive element
CRT/DRE
GBS
genotyping-by-sequencing
InDel
insertion and deletion
LD
linkage disequilibrium
marker-assisted selection
MAS
next-generation sequencing
NGS
QTL
quantitative trait loci
random amplified polymorphic DNA
RAPD
restriction fragment length polymorphism
RFLP
SCAR
sequence related amplified polymorphism
sequence-characterized amplified region
single-nucleotide polymorphism
SNP
SRAP
TF
tolerance to freezing
Molecular physiology and breeding at the crossroads of cold hardiness improvement - Physiologia Plantarum 2013 - 64-74
Alfalfa (Medicago sativa L) is a major forage legume grown extensively worldwide with important agronomic and environmental attributes. Insufficient cold hardiness is a major impediment to its reliable production in northern climates. Improvement of freezing tolerance using conventional breeding approaches is slowed by the quantitative nature of inheritance and strong interactions with the environment. The development of gene-based markers would facilitate the identification of genotypes with superior stress tolerance. Successive cycles of recurrent selection were applied using an indoor screening method to develop populations with significantly higher tolerance to freezing (TF). Bulk segregant analysis of heterogeneous TF populations identified DNA variations that are progressively enriched in frequency in response to selection. Polymorphisms resulting from intragenic variations within a dehydrin gene were identified and could potentially lead to the development of robust selection tools. Our results illustrate the benefits of feedback interactions between germplasm development programs and molecular physiology for a deeper understanding of the molecular and genetic bases of cold hardiness.
AFLP
Amplified fragment length polymorphism
BSA
Bulk segregant analysis
CBF
CNV
cold-regulated
Copy number variation
COR
c-repeat binding factor
c-repeat/dehydration responsive element
CRT/DRE
GBS
genotyping-by-sequencing
InDel
insertion and deletion
LD
linkage disequilibrium
marker-assisted selection
MAS
next-generation sequencing
NGS
QTL
quantitative trait loci
random amplified polymorphic DNA
RAPD
restriction fragment length polymorphism
RFLP
SCAR
sequence related amplified polymorphism
sequence-characterized amplified region
single-nucleotide polymorphism
SNP
SRAP
TF
tolerance to freezing