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Identification of genomic regions determining the phenological development leading to floral transition in wheat (Triticum aestivum L.).

Båga M, Fowler DB, Chibbar RN - J. Exp. Bot. (2009)

Bottom Line: Alleles of the LT-tolerant parent, Norstar, delayed floral transition at all QTLs except at the 2A locus.Some of the QTL alleles delaying floral transition also increased the length of vegetative growth and delayed flowering time.The genes underlying the QTLs identified in this study encode factors involved in regional adaptation of cold hardy winter wheat.

View Article: PubMed Central - PubMed

Affiliation: Department of Plant Science, University of Saskatchewan, 51 Campus Drive, Saskatoon, Saskatchewan, S7N 5A8 Canada.

ABSTRACT
Autumn-seeded winter cereals acquire tolerance to freezing temperatures and become vernalized by exposure to low temperature (LT). The level of accumulated LT tolerance depends on the cold acclimation rate and factors controlling timing of floral transition at the shoot apical meristem. In this study, genomic loci controlling the floral transition time were mapped in a winter wheat (T. aestivum L.) doubled haploid (DH) mapping population segregating for LT tolerance and rate of phenological development. The final leaf number (FLN), days to FLN, and days to anthesis were determined for 142 DH lines grown with and without vernalization in controlled environments. Analysis of trait data by composite interval mapping (CIM) identified 11 genomic regions that carried quantitative trait loci (QTLs) for the developmental traits studied. CIM analysis showed that the time for floral transition in both vernalized and non-vernalized plants was controlled by common QTL regions on chromosomes 1B, 2A, 2B, 6A and 7A. A QTL identified on chromosome 4A influenced floral transition time only in vernalized plants. Alleles of the LT-tolerant parent, Norstar, delayed floral transition at all QTLs except at the 2A locus. Some of the QTL alleles delaying floral transition also increased the length of vegetative growth and delayed flowering time. The genes underlying the QTLs identified in this study encode factors involved in regional adaptation of cold hardy winter wheat.

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Related in: MedlinePlus

Frequency distribution of average trait values in the Norstar×winter Manitou DH population. Trait values for parents, Norstar (N), and winter Manitou (wM) are indicated. (This figure is available in colour at JXB online.)
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fig1: Frequency distribution of average trait values in the Norstar×winter Manitou DH population. Trait values for parents, Norstar (N), and winter Manitou (wM) are indicated. (This figure is available in colour at JXB online.)

Mentions: The non-vernalized DH lines of the Norstar×winter Manitou population showed FLN values ranging from 16 to 24 leaves, dFLN varied from 90 d to 147 d, and dANT values were from 103 d to 151 d (Fig. 1). The trait values for the DH lines followed a normal distribution, with slight transgressive segregation towards the Norstar values.


Identification of genomic regions determining the phenological development leading to floral transition in wheat (Triticum aestivum L.).

Båga M, Fowler DB, Chibbar RN - J. Exp. Bot. (2009)

Frequency distribution of average trait values in the Norstar×winter Manitou DH population. Trait values for parents, Norstar (N), and winter Manitou (wM) are indicated. (This figure is available in colour at JXB online.)
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC2724704&req=5

fig1: Frequency distribution of average trait values in the Norstar×winter Manitou DH population. Trait values for parents, Norstar (N), and winter Manitou (wM) are indicated. (This figure is available in colour at JXB online.)
Mentions: The non-vernalized DH lines of the Norstar×winter Manitou population showed FLN values ranging from 16 to 24 leaves, dFLN varied from 90 d to 147 d, and dANT values were from 103 d to 151 d (Fig. 1). The trait values for the DH lines followed a normal distribution, with slight transgressive segregation towards the Norstar values.

Bottom Line: Alleles of the LT-tolerant parent, Norstar, delayed floral transition at all QTLs except at the 2A locus.Some of the QTL alleles delaying floral transition also increased the length of vegetative growth and delayed flowering time.The genes underlying the QTLs identified in this study encode factors involved in regional adaptation of cold hardy winter wheat.

View Article: PubMed Central - PubMed

Affiliation: Department of Plant Science, University of Saskatchewan, 51 Campus Drive, Saskatoon, Saskatchewan, S7N 5A8 Canada.

ABSTRACT
Autumn-seeded winter cereals acquire tolerance to freezing temperatures and become vernalized by exposure to low temperature (LT). The level of accumulated LT tolerance depends on the cold acclimation rate and factors controlling timing of floral transition at the shoot apical meristem. In this study, genomic loci controlling the floral transition time were mapped in a winter wheat (T. aestivum L.) doubled haploid (DH) mapping population segregating for LT tolerance and rate of phenological development. The final leaf number (FLN), days to FLN, and days to anthesis were determined for 142 DH lines grown with and without vernalization in controlled environments. Analysis of trait data by composite interval mapping (CIM) identified 11 genomic regions that carried quantitative trait loci (QTLs) for the developmental traits studied. CIM analysis showed that the time for floral transition in both vernalized and non-vernalized plants was controlled by common QTL regions on chromosomes 1B, 2A, 2B, 6A and 7A. A QTL identified on chromosome 4A influenced floral transition time only in vernalized plants. Alleles of the LT-tolerant parent, Norstar, delayed floral transition at all QTLs except at the 2A locus. Some of the QTL alleles delaying floral transition also increased the length of vegetative growth and delayed flowering time. The genes underlying the QTLs identified in this study encode factors involved in regional adaptation of cold hardy winter wheat.

Show MeSH
Related in: MedlinePlus