Two durum wheat varieties, Saturn-1 and Neptun-2, were used in the production of
), thus generating two amphiploid lines, designated A1 and A2, respectively. Anther culture response was studied involving callus induction, plant regeneration, albino- and green plants produced. The wild wheat parent did not respond to any of the parameters studied while the tetraploid wheats yielded only albino plants. Amphiploid lines differed in between for plant regeneration ability and produced albino and green plants, ranging from 1.9–3.2 and 0.4–0.8 per 100 plated anthers, respectively. Thus, the lines reacted equally in androgenesis for green plant yields and might be of use in the haploid wheat production.
Authors:I. Szedljak, K. Szántai-Kőhegyi, M. Tóth, and B. Bernhardt
Millet has attracted a great deal of interest due to its valuable agricultural, nutritional, and functional properties. In this study the aim was the investigation of millet usability in dry pasta products. Chemical, enzymological, and sensory parameters were measured and monitored in Triticum aestivum, Triticum durum, and millet containing pasta products during a 12-month-long storage period. According to our results, during the storage, millet had a strong effect on different parameters: because of increased acid value, the shelf life was reduced, and millet significantly influenced the pH value and the water soluble polyphenol content. The highest scores were measured in T. durum and T. durum-millet pasta samples in the sensory test, while the T. aestivum-millet mixture pasta got the lowest scores. Also in our experiment we tested how the drying temperature modifies polyphenol oxidase enzyme (PPO) activity right after drying and during storage. The samples containing millet flour had higher PPO activity in all cases after drying, while pasta made with T. durum had the lowest PPO activity. Our results showed that drying temperature has a significant impact on PPO activity.
Authors:O. Tereshchenko, E. Gordeeva, V. Arbuzova, A. Börner, and E. Khlestkina
Previously, it was suggested that purple grain colour was transferred to bread wheat from purple-grained tetraploid T. durum. In the current study, we demonstrated that the D genome of bread wheat ‘Purple’ carries one of two complementary genes determining purple grain colour. This gene was mapped on the short arm of chromosome 7D 2.5 cM distal to the locus Rc-D1 determining red coleoptile colour. This position is highly comparable with that of the Pp1 gene mapped earlier on the short arm of chromosome 7B in tetraploid T. durum.We suggest the Pp genes on T. durum chromosome 7B and T. aestivum chromosome 7D are orthologous. We designated them Pp-B1 and Pp-D1, respectively. Microsatellite-based genotyping of near-isogenic lines ‘i:S29Pp1Pp2PF’ and ‘i:S29Pp1Pp3P’, their recurrent (T. aestivum ‘Saratovskaya 29’) and donor (T. aestivum ‘Purple Feed’ and ‘Purple’, respectively) parents showed the presence of donor introgressions on chromosomes 2A and 7D in both near-isogenic lines. In addition to previously described purple pericarp, anthers and culms, phenotyping of these lines in the current study showed dark red coleoptile colour (with anthocyanin contents four times higher than in ‘Saratovskaya 29’ coleoptiles) and purple leaf blade and leaf sheath colour. It was concluded that each of the lines ‘i:S29Pp1Pp2PF’ and ‘i:S29Pp1Pp3P’ carry clusters of genes Rc-D1, Pc-D1, Pan-D1, Plb-D1, Pls-D1 and Pp-D1 on chromosome 7D between microsatellite markers Xgwm0044 and Xgwm0676.
One basic precondition for the reliable cultivation of winter durum wheat (Triticum durum Desf.) in Hungary is for the varieties to have good winter hardiness and frost resistance. Field overwintering experiments carried out in Martonvásár between 1995 and 2003 demonstrated that there was a significant difference every year between the overwintering of varieties with poor and good frost resistance, though only in two years was there a significant difference between that of varieties with medium and better frost resistance. Only a medium correlation was observed between the mean annual values of the air temperature in the winter months and the winter hardiness of the varieties, confirming that winter hardiness is influenced jointly by a number of environmental factors (e.g. cold, snow cover). In the experiments carried out on the winter hardiness dynamics of durum wheat, it was found that in milder winters even T. durum varieties which are sensitive to frost overwintered with little damage, while in the two coldest winters during the experimental period the hardiness of these varieties did not provide sufficient protection even in December, and all the plants were destroyed by January. The early spring frosts experienced in 1996 proved in these experiments that spring frosts may cause considerable damage even to durum wheat varieties with relatively good winter hardiness. Averaged over eight years, the results prove that T. durum genotypes are now available whose average state of hardening and winter hardiness are equal or better than those of winter T. aestivum varieties with moderate frost resistance.
Authors:M. Pereyra, R. González, C. Creus, and C. Barassi
Data evaluating the growth promoting effects of
on wheat seedlings according to the inoculum level/root colonization effectiveness (number of bacterial cells), is scarce. Uniform 1-cm size, 72-h old wheat seedlings grown in the dark at 22 °C were inoculated with: i) 10
cv. ProINTA Federal seedling; ii) 10
cv. Buck Topacio seedling; iii) 10
heat killed bacteria (HKB) cells per cultivar seedling; iv) phosphate buffer pH 6.8 (NI) as control seedlings for both cultivars. Afterwards, seedling growth proceeded in water in the dark at 22 °C for another 48 h. Alive or dead
cells were suspended in phosphate buffer pH 6.8. Root and shoot growth were determined measuring the length and projected area of their digitalized images. When treated with inocula concentrations ranging from 10
cells per seedling, both
species reached a maximum level of colonization harboring 10
cells per seedling. No differences could be detected between NI and HKB treated seedlings for both
cv. ProINTA Federal seedlings reached the maximum growth promotion when roots were colonized with a number of bacterial cells ranging from 5 · 10
to 1.5 · 10
cv. Buck Topacio seedlings showed maximum growth promotion when 3.3 · 10
cells were present in their roots. Higher values of colonization showed no growth promoting effects with respect to the controls. It may be concluded that in these experimental conditions the optimum inoculum concentration is 5 · 10
cells per seedling for both
cv. ProINTA Federal and
cv. Buck Topacio.
Authors:O. Tereshchenko, T. Pshenichnikova, E. Salina, and E. Khlestkina
Purple colour of wheat grain is determined by anthocyanin accumulation in the pericarp. This trait is controlled in hexaploid Triticum aestivum or tetraploid T. durum wheats by two complementary dominant genes Pp1 (chromosome 7B) and Pp3 (chromosome 2A). It remained unclear, whether functional alleles of one of the two complementary Pp genes occur in the diploid progenitors of allopolyploid wheat or in tetraploid T. timopheevii. In the current study, a purple-grained wheat line PC was obtained by crossing non-purple-grained T. aestivum Line 821 and Line 102/00i carrying introgressions from T. timopheevii and Aegilops speltoides, respectively. Crosses of lines 821 and 102/00i with a number of tester lines and cultivars did not result in purple-grained genotypes suggesting that expression of this trait in PC was controlled by complementary factors, one located in the T. timopheevii introgression and the other in the introgression inherited from Ae. speltoides. Genotyping of PC and other parental lines using microsatellite markers located on wheat chromosomes 7B and 2A showed that PC carries chromosome 7S of Ae. speltoides substituting for chromosome 7B, whereas chromosome 2A of PC contains an extended introgression from T. timopheevii.
Authors:N. Daskalova, S. Doneva, Y. Stanoeva, I. Belchev, and P. Spetsov
Four amphiploid lines (SHW) based on T. monococcum (Tm) and T. boeoticum (Tb) were crossed to T. durum varieties to generate 13 combinations. Field germination and winter survival of hybrid plants in F2 were assessed. Among all crosses, those with SHW8A-Tb and SHW9A-Tm showed highest field germination but with different degrees of spike fragility. The variation on seed number and weight per main spike was studied in F4–6 from SHW8ATb/ Progres and SHW5A-Tb/Severina crosses after individual selection for these traits. Ten lines with durum phenotype from the former and three genotypes with dicoccum plant shape from the latter cross were developed. SDS-PAGE indicated the presence of HMW-GS 1Ax2*+1Aynull subunits in four lines, among which 1Ax2* was inherited from T. boeoticum acc.110 through SHW8A-Tb. Most of the selected genotypes possessed γ-gliadin45, which was relating to good end-use quality. Powdery mildew testing showed that all progenies resulted from the SHW8A-Tb/Progres were susceptible to 12 races of the pathogen, while three lines derived from the SHW5A-Tb/Severina cross behaved differently: G32 expressed resistance to six, G33 to 2, and G34 to 5 races. The selected genotypes from crosses involving SHW with T. boeoticum exhibited good breeding performance compared to tetraploid wheat parents, and might be of breeding interest to further research.
Wheat genotypes from various Triticum L. genus species (
L.) were analysed by stereological analysis in order to explore the existence of inter-species differences and similarities in anatomical characteristics of wheat flag leaf tissue. The genotypes of the tetraploid species did not differ significantly among themselves in the volume density of the analysed tissues of the flag leaf. Among the hexaploid species, the results showed highly significant differences in volume density of the photosynthetic tissue and volume density of the mechanical tissue; and significant differences for the volume density of the vascular tissue. The analysis of the main vein of the flag leaf showed smaller volumes of the vascular tissue in hexaploid species — of the phloem and parenchyma of the main vein. The analysed species showed the greatest difference in the volume of the main vein, the parenchyma of the main vein and the mechanical tissue. When compared to the volume and volume density of the xylem of the main vein, the tetraploid species had greater volumes and volume densities of the mechanical tissue of the main vein. With hexaploid species the results were reverse.
Authors:A. Pour-Aboughadareh, J. Ahmadi, A.A. Mehrabi, A. Etminan, and M. Moghaddam
The knowledge about genetic diversity in the wild relatives of wheat provides useful information for breeding programs and gene pool management. In the present study, an assessment of agro-morphological diversity and molecular variability among 70 accessions of Triticum, belonging to T. boeoticum, T. urartu, T. durum and T. aestivum species, collected from different regions of Iran was made. According to phenotypic analysis, all traits except peduncle length, stem diameter and the number of seeds per spike indicated a high level of diversity among studied accessions. Also, principal component analysis identified six components that explained 87.53% of the total variation in agro-morphological traits. In molecular analysis, 15 start codon targeted (SCoT) polymorphism primers produced 166 bands, out of which, 162 (97.59%) were polymorphic. Analysis of molecular variance (AMOVA) indicated the 63% of the variation resided among populations. The maximum value of polymorphism information content (PIC), the observed (Na) and effective (Ne) number of alleles, Nie’s gene diversity (He) and Shannon’s information index (I) was detected for T. boeoticum than the other species. The SCoT-based tree revealed three different groups corresponding to the genomic constitution in Triticum germplasm, which was in part confirmed by STRUCTURE and principal coordinate (PCoA) analyses. Our results indicated a remarkable level of genetic diversity among studied Iranian Triticum species, especially T. boeoticum, which can be of interest for future breeding and other analyses associated with future studies of the wild relatives of wheat. More importantly, our results revealed that SCoT markers could be used to accurate evaluate genetic diversity and phylogenetic relationships among different Triticum species.