Genetic effects of Vrn genes on heading date and agronomic traits in bread wheat

Stelmakh, A. F.

doi:10.1007/bf00022199

Cited by 96 publications

(71 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…For example, the presence of the dominant Vrn-A1 allele results in complete elimination of the vernalization requirement, whereas the presence of the dominant Vrn-D1 allele is associated with some residual vernalization requirement (Halloran 1967;Maystrenko 1974;Kato and Yamagata 1988). Spring varieties including the dominant Vrn-A1 allele are usually earlier than those including only combinations of the dominant Vrn-B1 and Vrn-D1 alleles (Stelmakh 1993).…”

Section: Intronic Regulatory Elementsmentioning

confidence: 99%

Large deletions within the first intron in VRN-1 are associated with spring growth habit in barley and wheat

et al. 2005

View full text Add to dashboard Cite

The broad adaptability of wheat and barley is in part attributable to their flexible growth habit, in that spring forms have recurrently evolved from the ancestral winter growth habit. In diploid wheat and barley growth habit is determined by allelic variation at the VRN-1 and/or VRN-2 loci, whereas in the polyploid wheat species it is determined primarily by allelic variation at VRN-1. Dominant Vrn-A1 alleles for spring growth habit are frequently associated with mutations in the promoter region in diploid wheat and in the A genome of common wheat. However, several dominant Vrn-A1, Vrn-B1, Vrn-D1 (common wheat) and Vrn-H1 (barley) alleles show no polymorphisms in the promoter region relative to their respective recessive alleles. In this study, we sequenced the complete VRN-1 gene from these accessions and found that all of them have large deletions within the first intron, which overlap in a 4-kb region. Furthermore, a 2.8-kb segment within the 4-kb region showed high sequence conservation among the different recessive alleles. PCR markers for these deletions showed that similar deletions were present in all the accessions with known Vrn-B1 and Vrn-D1 alleles, and in 51 hexaploid spring wheat accessions previously shown to have no polymorphisms in the VRN-A1 promoter region. Twenty-four tetraploid wheat accessions had a similar deletion in VRN-A1 intron 1. We hypothesize that the 2.8-kb conserved region includes regulatory elements important for the vernalization requirement. Epistatic interactions between VRN-H2 and the VRN-H1 allele with the intron 1 deletion suggest that the deleted region may include a recognition site for the flowering repression mediated by the product of the VRN-H2 gene of barley.

show abstract

Section: Intronic Regulatory Elementsmentioning

confidence: 99%

Large deletions within the first intron in VRN-1 are associated with spring growth habit in barley and wheat

et al. 2005

View full text Add to dashboard Cite

show abstract

“…However, for developing widely adapted wheat cultivars, the use of vernalization responsive genes in combination with nonresponsive genes has been recommended (Stelmakh 1993;Jedel 1994). Our results suggest that additive gene action plays a major role in the inheritance of both vernalization response and earliness per se.…”

Section: Methodsmentioning

confidence: 87%

A genetic examination of early flowering and maturity in Canadian spring wheat

Iqbal¹,

Navabi²,

Salmon³

et al. 2006

Can. J. Plant Sci.

View full text Add to dashboard Cite

A genetic examination of early flowering and maturity in Canadian spring wheat. Can. J. Plant Sci. 86: 995-1004. Under short-season western Canadian growing conditions, vernalization non-responsiveness is generally considered a preferable spring wheat (Triticum aestivum L.) phenotype, to avoid inconsistent maturity and yield patterns. The objectives of this study were to investigate the genetic factors affecting early flowering and maturity, and related agronomic traits, in a set of five Canadian spring wheat cultivars. The cultivars were first studied under 10-and 16-h photoperiods and 0-and 42-d vernalization treatments. Thereafter, the parents and F 1 hybrids from a one-way diallel mating design were grown with and without a 42-d vernalization treatment. Shorter photoperiod delayed flowering time in all cultivars, and increased final leaf number in AC Barrie. Vernalization hastened flowering and decreased final leaf number in AC Foremost and AC Taber. AC Foremost and AC Taber carry at least one different allele, from the rest of the cultivars studied, at the major loci governing vernalization response. Leaf and spikelet number on the main culm, days to anthesis and maturity, tiller number and yield plant -1 were mainly controlled by additive gene action. Narrow-sense heritability was medium to high (0.53-0.93) for final leaf number, days to anthesis, spikelet number and grain yield, but low to medium (0.20-0.71) for days to maturity and tiller number. Selection for early flowering under non-vernalizing conditions may aid in the breeding of (vernalization non-responsive) early-maturing spring wheat cultivars in western Canada. Early maturity is an important objective of spring wheat breeding programs in northern growing regions. Short growing seasons, low temperatures early and late in the growing season, and long days (>14 h) typify regions such as the Canadian prairies. Due to the short growing season (95-125 d) in western Canada, the development of earlymaturing cultivars is important to avoid frost damage, which can adversely affect production and quality. Early maturing cultivars may also be less prone to pre-harvest sprouting (Hucl and Matus-Cadiz 2002), which is common in years of cold and wet harvest conditions. Growth and developmental phases (tillering, stem elongation, ear emergence, anthesis and ripening) of wheat are controlled by vernalization and photoperiod response, and earliness per se genes (Kosner and Pankova 1998

show abstract

“…Therefore, wheat cultivars with dominant Vrn-A1 allele flower the earliest, whereas those with dominant Vrn-D1, Vrn-D5 and/or Vrn-B1 flower later, respectively, under non-vernalizing conditions (Goncharov, 2004). Besides altering flowering time, different combinations of dominant Vrn alleles may also cause variation in plant height and yield components in wheat (Stelmakh, 1992;Stelmakh, 1998). The presence of two dominant alleles at major vernalization loci confers early maturity as well as higher yield potential.…”

Section: Introductionmentioning

confidence: 99%

Allelic variation at the Vrn-A1, Vrn-B1, Vrn-D1, Vrn-B3 and Ppd-D1a loci of Pakistani spring wheat cultivars

Iqbal¹,

Shahzad²,

Ahmed³

2001

Electron. J. Biotechnol.

View full text Add to dashboard Cite

Flowering time in bread wheat (Triticum aestivum L.) is controlled by vernalization and photoperiod response, and earliness per se genes. The genetic basis of flowering time has not been investigated in Pakistani bread wheat. This study was, therefore, conducted to determine the allelic composition at Vrn-A1, Vrn-B1, Vrn-D1, Vrn-B3 and Ppd-D1a loci of 59 Pakistani spring bread wheat cultivars. These cultivars, along with 4 isogenic lines for vernalization genes were characterized with previously reported DNA markers designed for detecting allelic variation at 4 Vrn (Vernalization) and 1 Ppd (Photoperiod) loci. Spring habit Vrn-A1a allele was found in 36% cultivars either alone or with spring habit Vrn-B1 and Vrn-D1 alleles. Two wheat cultivars had the dominant Vrn-A1c allele, whereas none of the cultivars had Vrn-A1b. Spring habit Vrn-B1 was the most frequent allele (64%) present either alone or with Vrn-A1a, Vrn-A1c and Vrn-D1. Spring habit Vrn-D1 was found in 61% cultivars. Vrn-D1 was singly found in 25% cultivars and along with Vrn-B1 in 29% cultivars. Dominant Vrn-B3 was absent in all cultivars studied. All cultivars except Era had the photoperiod insensitive allele PpdD1a. We did not find any association between the flowering time and Vrn allelic composition of the studied cultivars. This indicated that the partial vernalization requirement of cultivars with Vrn-B1 and Vrn-D1 alleles is probably fulfilled during Pakistani growing season. Earliness per se and the photoperiod sensitive loci other than Ppd-D1 need to be investigated to further understand the genetic basis of flowering time in Pakistani wheat.

show abstract

Genetic effects of Vrn genes on heading date and agronomic traits in bread wheat

Cited by 96 publications

References 4 publications

Large deletions within the first intron in VRN-1 are associated with spring growth habit in barley and wheat

Large deletions within the first intron in VRN-1 are associated with spring growth habit in barley and wheat

A genetic examination of early flowering and maturity in Canadian spring wheat

Allelic variation at the Vrn-A1, Vrn-B1, Vrn-D1, Vrn-B3 and Ppd-D1a loci of Pakistani spring wheat cultivars

Contact Info

Product

Resources

About