A phenotypic screen for genetic analysis of Scottish Crop
Transcript Of A phenotypic screen for genetic analysis of Scottish Crop
A phenotypic screen for genetic analysis of barley seedling root traits
D C Gordon, A G Bengough, S. Clark, H. S. Al-menaie, W T B Thomas And B P Forster Scottish Crop Research Institute, Invergowrie, Dundee DD2 5DA Scotland.
®
Scottish Crop Research Institute
Introduction
Genetic studies of root traits have been hampered by the lack of high throughput phenotyping, i.e. techniques designed to screen a large number of lines (> 100) in replicated experiments. A non-destructive two-dimensional chamber has been designed to observe seminal roots in cereals (Bengough et al., 2004). The usefulness of the two-dimensional observation chambers has been tested in assessing the genetic diversity in the barley gene pool and in genetic mapping of seedling root traits.
Development of a two-dimensional seedling root screen
The test involves placing chitted uniform seed between two gel-coated plates (one black, one transparent of A4 size). The plates are clamped together, leaving a narrow air space between the gel layers. The chambers are incubated upright in the dark at 10 12ºC for 10 days. Images of the developing root system are captured over time and analysed using appropriate software. Traits measured included root number, spread of roots and individual and total root length, growth rates can also be calculated. The results in the gel system are similar to those observed in a 2-D soil system.
Screening a wide range of barley germplasm
Wild
Landrace
Cultivated
Mutant
Wild barley lines tested produced relatively few seminal roots with a narrow spread, this contrasted markedly with cultivated which produced twice as many roots with a wide spread, the landrace line tested was
intermediate. We also tested over 100 mutant lines of barley which exhibit aerial morphological variation. Some of these also showed distinctive root morphologies, e.g. curly roots.
Head(UK)Yield(UK)TotalRSS(All)-
RSS3Head(EgI)Hght(EgR)+ Head(EgR)Yield(EgR)+
High through put screening and genetic mapping
1H
3H
4H
The 2-D test was used to screen a
Spread+
TotRootL+
Hght(Mo)+
genetic mapping population, 156
5H
7H
Hght(UK)+
Head(UK)+
RootNo+
RSS3+
ShootL+
LRootL+
Hght(EgI)+
Hght(EgR)+
Hght(Mo)+
Spread+
Head(Mo)+ Head(Mo)-
doubled haploid lines derived from
Ari-eGP
the cross Derkado x B83-12/21/5
(Thomas, 2003) with four
Spread+ Hght(EgR)-
TotalRSS(All)Hght(UK)+ Head(Mo)-
replications. Quantitative trait loci
were detected for seedling root
SpreadYield(EgI)+
Yield(Mo)+ Head(EgR)-
Head(Mo)-
TotalRSS(All)Head(UK)-
Yield(UK)- Yield(EgR)-
number (RootNo), spread (Spread)
mlo
RSS1&2(All)+ ShDeltaC-
Hght(UK)Head(UK)+ Head(Mo)+
Yield(Tu)+ Yield(Mo)Yield(EgR)-
Head(Tu)+ Head(EgI)+ Head(EgR)+ Hght(EgI)Hght(EgR)Hght(Mo)Hght(EgR)-
and length (RootL), and compared sdw1
with QTL for adult plant root system
size (RSS) and other field
performance traits (yield and height)
Genetic location of root QTLs
References
Bengough A G, Gordon D C, Al-Menaie H S, Allan D, Keith R, Thomas W T B, Forster B P. 2004. Gel observation chamber for rapid screening of root traits in cereal seedlings. Plant and Soil 262: 63-70.
Thomas, W.T.B. 2003. Prospect for molecular breeding of barley. Annals of Applied Biology 142: 1-12
D C Gordon, A G Bengough, S. Clark, H. S. Al-menaie, W T B Thomas And B P Forster Scottish Crop Research Institute, Invergowrie, Dundee DD2 5DA Scotland.
®
Scottish Crop Research Institute
Introduction
Genetic studies of root traits have been hampered by the lack of high throughput phenotyping, i.e. techniques designed to screen a large number of lines (> 100) in replicated experiments. A non-destructive two-dimensional chamber has been designed to observe seminal roots in cereals (Bengough et al., 2004). The usefulness of the two-dimensional observation chambers has been tested in assessing the genetic diversity in the barley gene pool and in genetic mapping of seedling root traits.
Development of a two-dimensional seedling root screen
The test involves placing chitted uniform seed between two gel-coated plates (one black, one transparent of A4 size). The plates are clamped together, leaving a narrow air space between the gel layers. The chambers are incubated upright in the dark at 10 12ºC for 10 days. Images of the developing root system are captured over time and analysed using appropriate software. Traits measured included root number, spread of roots and individual and total root length, growth rates can also be calculated. The results in the gel system are similar to those observed in a 2-D soil system.
Screening a wide range of barley germplasm
Wild
Landrace
Cultivated
Mutant
Wild barley lines tested produced relatively few seminal roots with a narrow spread, this contrasted markedly with cultivated which produced twice as many roots with a wide spread, the landrace line tested was
intermediate. We also tested over 100 mutant lines of barley which exhibit aerial morphological variation. Some of these also showed distinctive root morphologies, e.g. curly roots.
Head(UK)Yield(UK)TotalRSS(All)-
RSS3Head(EgI)Hght(EgR)+ Head(EgR)Yield(EgR)+
High through put screening and genetic mapping
1H
3H
4H
The 2-D test was used to screen a
Spread+
TotRootL+
Hght(Mo)+
genetic mapping population, 156
5H
7H
Hght(UK)+
Head(UK)+
RootNo+
RSS3+
ShootL+
LRootL+
Hght(EgI)+
Hght(EgR)+
Hght(Mo)+
Spread+
Head(Mo)+ Head(Mo)-
doubled haploid lines derived from
Ari-eGP
the cross Derkado x B83-12/21/5
(Thomas, 2003) with four
Spread+ Hght(EgR)-
TotalRSS(All)Hght(UK)+ Head(Mo)-
replications. Quantitative trait loci
were detected for seedling root
SpreadYield(EgI)+
Yield(Mo)+ Head(EgR)-
Head(Mo)-
TotalRSS(All)Head(UK)-
Yield(UK)- Yield(EgR)-
number (RootNo), spread (Spread)
mlo
RSS1&2(All)+ ShDeltaC-
Hght(UK)Head(UK)+ Head(Mo)+
Yield(Tu)+ Yield(Mo)Yield(EgR)-
Head(Tu)+ Head(EgI)+ Head(EgR)+ Hght(EgI)Hght(EgR)Hght(Mo)Hght(EgR)-
and length (RootL), and compared sdw1
with QTL for adult plant root system
size (RSS) and other field
performance traits (yield and height)
Genetic location of root QTLs
References
Bengough A G, Gordon D C, Al-Menaie H S, Allan D, Keith R, Thomas W T B, Forster B P. 2004. Gel observation chamber for rapid screening of root traits in cereal seedlings. Plant and Soil 262: 63-70.
Thomas, W.T.B. 2003. Prospect for molecular breeding of barley. Annals of Applied Biology 142: 1-12