47 research outputs found
Allele frequencies in the VRN-A1, VRN-B1 and VRN-D1 vernalization response and PPD-B1 and PPD-D1 photoperiod sensitivity genes, and their effects on heading in a diverse set of wheat cultivars (Triticum aestivum L.)
Heading of cereals is determined by
complex genetic and environmental factors in which
genes responsible for vernalization and photoperiod
sensitivity play a decisive role. Our aim was to use
diagnostic molecular markers to determine the main
allele types in
VRN
-
A1
,
VRN
-
B1
,
VRN
-
D1
,
PPD
-
B1
and
PPD
-
D1
in a worldwide wheat collection of 683
genotypes and to investigate the effect of these alleles
on heading in the field. The dominant
VRN
-
A1
,
VRN
-
B1
and
VRN
-
D1
alleles were present at a low
frequency. The
PPD
-
D1a
photoperiod-insensitive
allele was carried by 57 % of the cultivars and was
most frequent in Asian and European cultivars. The
PPD
-
B1
photoperiod-insensitive allele was carried by
22 % of the genotypes from Asia, America and
Europe. Nine versions of the
PPD
-
B1
-insensitive
allele were identified based on gene copy number
and intercopy structure. The allele compositions in
PPD
-
D1
,
PPD
-
B1
and
VRN
-
D1
significantly influ-
enced heading and together explained 37.5 % of the
phenotypic variance. The role of gene model increased
to 39.1 % when
PPD
-
B1
intercopy structure was taken
into account instead of overall
PPD
-
B1
type (sensitive
vs. insensitive). As a single component,
PPD
-
D1
had
the most important role (28.0 % of the phenotypic
variance), followed by
PPD
-
B1
(12.3 % for
PPD
-
B1
_overall, and 15.1 % for
PPD
-
B1
_intercopy) and
VRN
-
D1
(2.2 %). Significant gene interactions were
identified between the marker alleles within
PPD
-
B1
and between
VRN
-
D1
and the two
PPD1
genes. The
earliest heading genotypes were those with the pho-
toperiod-insensitive allele in
PPD
-
D1
and
PPD
-
B1
,
and with the spring allele for
VRN
-
D1
and the winter
alleles for
VRN
-
A1
and
VRN
-
B1
. This combination
could only be detected in genotypes from Southern
Europe and Asia. Late-heading genotypes had the
sensitivity alleles for both
PPD1
genes, regardless of
the allelic composition of the
VRN1
genes. There was
a 10-day difference in heading between the earliest
and latest groups under field conditions
Effect of genotypic, meteorological and agronomic factors on the gluten index of winter durum wheat
The determination of the gluten index is a widely used method for analysing the gluten strength of bread wheat and spring durum wheat genotypes. The present work was carried out to study the effect of the genotype, meteorological factors (temperature, precipitation and number of days with Tmax ≥ 30 °C) and agronomic treatments (N fertilisation and plant protection) on the gluten index of winter durum wheat varieties and breeding lines. The results indicated that the gluten index had little dependence on the environment, being determined to the greatest extent by the genotype. Compared with varieties having weak gluten, those with a strong gluten matrix responded less sensitively to changes in environmental conditions. Among the meteorological factors, high temperature at the end of the grain-filling period caused the greatest reduction in the mean gluten index of three varieties (R 2 = 0.462), while the fertiliser was found to be a significant factor affecting the gluten strength of winter durum wheat varieties. Using selection based on the gluten index, the gluten strength of winter durum wheat lines can be improved sufficiently to make them competitive with high quality spring varieties
Variation in the Content and Composition of Tocols in a Wheat Population
Wheat is a well-known source of B vitamins but also contains significant amounts of vitamin E and related tocols, which have a number of positive health benefits. However, there are no reports on increasing the tocol content of wheat. A prerequisite for increasing the tocol content is the identification of variation in its amount within wheat and related cereals. We therefore determined the tocol content and composition in the grain of 230 recombinant inbred lines (RILs) of a diverse biparental wheat population (Mv Toborzó/Tommi), showing variation in the total content from 13.69 to 45.18 μg/g d.m. The total content also showed transgressive segregation in the population. The effect of the genotype on the variance components of tocols was studied, and the broad-sense heritability was calculated to be 0.71. The lines were also grouped based on their tocol content and analyzed for their chemical composition and breadmaking quality. The high heritability value and the wide variation found in the total amount indicate that increasing the content of tocols is a possible breeding strategy
Variation in the Content and Composition of Tocols in a Wheat Population
Wheat is a well-known source of B vitamins but also contains significant amounts of vitamin E and related tocols, which have a number of positive health benefits. However, there are no reports on increasing the tocol content of wheat. A prerequisite for increasing the tocol content is the identification of variation in its amount within wheat and related cereals. We therefore determined the tocol content and composition in the grain of 230 recombinant inbred lines (RILs) of a diverse biparental wheat population (Mv Toborzo/Tommi), showing variation in the total content from 13.69 to 45.18 mu g/g d.m. The total content also showed transgressive segregation in the population. The effect of the genotype on the variance components of tocols was studied, and the broad-sense heritability was calculated to be 0.71. The lines were also grouped based on their tocol content and analyzed for their chemical composition and breadmaking quality. The high heritability value and the wide variation found in the total amount indicate that increasing the content of tocols is a possible breeding strategy.Peer reviewe
Variation in the Content and Composition of Tocols in a Wheat Population
Wheat is a well-known source of B vitamins but also contains significant amounts of vitamin E and related tocols, which have a number of positive health benefits. However, there are no reports on increasing the tocol content of wheat. A prerequisite for increasing the tocol content is the identification of variation in its amount within wheat and related cereals. We therefore determined the tocol content and composition in the grain of 230 recombinant inbred lines (RILs) of a diverse biparental wheat population (Mv Toborzó/Tommi), showing variation in the total content from 13.69 to 45.18 μg/g d.m. The total content also showed transgressive segregation in the population. The effect of the genotype on the variance components of tocols was studied, and the broad-sense heritability was calculated to be 0.71. The lines were also grouped based on their tocol content and analyzed for their chemical composition and breadmaking quality. The high heritability value and the wide variation found in the total amount indicate that increasing the content of tocols is a possible breeding strategy