ABSTRACT: 1201 published maize QTLs conferring for 68 traits were collected and imported into local C Map software to construct an integrated
QTL map, which can be used for marker-mining, QTL localization, gene cloning and marker-assisted selection. The maize integrated
QTL map showed that maize QTLs for various traits usually clustered in all chromosomes. 22 plant height QTLs of maize were
co-linear with 64 plant height QTLs of rice, 43 grain yield QTLs of maize were co-liner with 7 grain yield QTLs of rice. 127
plant height QTLs of maize were refined by means of “overview” analysis. At last, 40 “real” QTLs were identified. A substantial
number of candidate quantitative trait genes for plant height of maize were found. These results established an important
bioinformatics platform for extracting most of maize QTL information.
Chinese Science Bulletin 04/2012; 51(18):2219-2230. · 1.32 Impact Factor
ABSTRACT: Association mapping is a powerful approach to identify associations between traits of interest and genetic markers. In this study, 103 wheat germplasm accessions from China were genotyped using 76 SSR markers and 40 EST-SSR markers. The phenotyping of plant height, spike length, spikelets per spike, spikelets density, grains per spike and thousand-kernel weight were carried out in three locations for three years. Six subpopulations were identified among these accessions by population structure analysis based on 49 SSR and 40 EST-SSR markers. Linkage disequilibrium (LD) on chromosome 4A extended up to ~3 cM with r 2 =0.054. Based on the mixed linear model considering population structure and relative kinship, a total of 10 SSR markers (p<0.01) on chromosome 4A were significantly associated with six agronomic traits, and six of them were associated with multiple traits. Some of the associated markers were in agreement with previous quantitative trait loci (QTL) analysis. This study demonstrated that association mapping can be successfully applied in wheat breeding context for detection of marker-traits associations. Furthermore, association mapping can enhance previous QTL information and provide additional QTL information for marker-assisted selection.
Molecular Plant Breeding Authors Molecular Plant Breeding Accepted: Oct. Published: Oct. 01/2010; 1(30).
ABSTRACT: Association mapping is a method to test the association between molecular markers and quantitative trait loci (QTL) based on linkage disequilibrium (LD). In this study, the collection of 108 wheat germplasm accessions form China were evaluated for their plant heights, spike length, spikelets per spike, grains per spike, thousand kernel weight and spikelets density in 3 years at three locations. And they were genotyped with 85 SSR markers and 40 EST-SSR markers. The population structure was inferred on the basis of unlinked 48 SSR markers and 40 EST-SSR markers. The extent of LD on chromosome 2A was 2.3 cM. Association of 37 SSR loci on chromosomes 2A with six agronomic traits was analysed with a mixed linear model. A total of 14 SSR loci were significantly associated with agronomic traits. Some of the associated markers were located in the QTL region detected in previous linkage mapping analysis. Our results demonstrated that association mapping can enhance QTL information and achieves higher resolution with short LD extent.
Genetica 02/2009; 137(1):67-75. · 2.15 Impact Factor