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In a scenario of climate change and rapidly rising urban populations demanding processed foods, it is necessary to develop new wheat cultivars combining high yield potential, disease resistance, and stability for yield and processing quality, even under heat or drought stress conditions. Allelic variation for gluten proteins (glutenin subunits and gliadins) is a major determinant of differences in dough viscoelastic properties observed between cultivars of both bread wheat and durum wheat. Technical difficulties in allelic identification due to the complexity of the protein profile produced by each cultivar and the use of different nomenclature systems in different laboratories has historically interfered with information exchange between research groups, a situation exacerbated by the vast number of possible profiles found in different cultivars due to the multi-allelic nature of the principal loci encoding gluten proteins (, , and ). For the alleles, we have collaborated to unify criteria across laboratories and to compare four different methods of allelic identification (SDS-PAGE, 2-DE, MALDI-TOF-MS and PCR), and have shown that the four methods can be regarded as complementary techniques for allelic identification. We seek to continue addressing remaining analytical challenges, place the findings in the context of the Catalogue of Gene Symbols for Wheat, and, with unified criteria, initiate work to define better the relationship between specific gluten proteins and processing quality attributes. Therefore, we propose a new system to share materials through public gene banks in collaboration with the Catalogue, and the formation of a wider international group aimed at facilitating the resolution of the remaining problems in the field. We also propose to extend our collaboration by forming a wheat quality expert working group under the Wheat Initiative.

Diverse technological purposes of bread wheat grain requires a broadening the genetic base of selection for quality traits. Introgressions potentially may affect technological properties of grain and flour and add to a genetic variability of the trait. The aim of this work was to investigate the influence of introgressions from exotic tetraploid wheat and wild cereal species, and into bread wheat on grain quality. The introgression from including the microsatellite marker into 2AS chromosome of cv. Saratovskaya 29 resulted in a significant increase of gluten content in grain. The effect was confirmed by re-introducing the recombinant chromosome again into the same genetic background. The analogous effect was observed in the line of winter cultivar Alcedo with the similar alien fragment in 2AS chromosome inherited from . Introgression of 5S chromosome of carrying the gene for grain softness into hard-grain bread wheat cultivars resulted in obtaining the genotypes with soft grain texture. Combining two dominant genes for grain softness and in one genotype allowed us to obtain the plants with grain having the new milling properties – very low vitreousness (about 30 %) and small particle size (about 10 μm).

Evaluation of wheat end-use quality in terms of loaf volume (LV) requires enormous time and labor inputs. Hence, many studies have attempted to use grain, flour and dough properties to predict LV. Many quantitative trait loci (QTL) underlying these traits have also been identified to facilitate breeding. However, correlations between such predictive tests and LV as well as their QTLs could be influenced by the environment. In this chapter, we review recent literature on the correlations and G × E interaction (GEI) of the bread making quality traits grain protein content (GPC), sodium dodecyl sulphate sedimentation volume (SV), dough rheological traits (DRT) and LV. We briefly discuss our results from the evaluation of a hexaploid wheat recombinant inbred line population for GPC, SV, LV and nine DRT by mixograph analysis in six year-location environments in India, which revealed that correlations between DRT and LV were not stable across environments. In addition, GEI measured in terms of principal components using Additive main effects and multiplicative interaction model showed up to 47 % contribution to the total variation of the traits, which was reflected in the location-specificity of QTLs expressed in single as well as multiple environments. Even though 16 QTL clusters for four to seven traits were identified, only one of them involved LV. The strong influence of the environment on complex interrelationships between DRT and the other end-use quality traits suggested that during breeding for wheat end-use quality, marker-based selection of these traits would be more efficient if specific agro-climatic zones are targeted separately.

The soft winter wheat variety, Kitahonami, shows a superior flour yield in comparison to other Japanese soft varieties. In order to map quantitative trait loci (QTL) associated with the flour-yield trait, association mapping was performed using panel lines in Kitahonami’s pedigree, along with leading varieties and advanced breeding lines. Using a mixed linear model corrected for kernel types and familial relatedness, 62 marker-trait associations were identified and classified into 21 QTLs. Five out of eight QTLs tested were validated by linkage analyses using three sets of doubled haploid populations from crosses in which Kitahonami was used as a parent. Among them, QTLs on 3B and 7A chromosome showed highly significant effects and consistency across the three populations. A joint linkage map of 3B showed that the QTL on this chromosome was located at the same interval across the populations. By applying a meta-analysis approach, we have succeeded in identifying QTLs with consistent contributions to high flour yield across various genetic backgrounds.

In Japan, the breeding of new wheat varieties for use in bread, Chinese noodles, as well as other noodles, is an urgently required objective if domestic wheat production and food self-sufficiency ratio have to increase. Many molecular markers are now available; those used in wheat breeding programs in Japan are generally to assess the amylose content, dough strength, grain hardness, wheat yellow mosaic virus, preharvest sprouting, and head blight. Hard and extra-strong wheat varieties have been released using marker-assisted selection.

A variety of diseases of wheat ( L.) occurs every year in the U.S. leading to significant grain yield losses. blotch (SNB), fusarium head blight (FHB) and stem rust (SR) are caused by the fungi and , respectively. These diseases penalize both grain yield and quality. Three resistance factors, , and conferring resistance, respectively, to SNB, FHB and SR, each from a unique donor wheat parent line, have been mapped to chromosome 3BS of wheat and are believed to be closely linked. Based on previously published analyses, is on the distal end, is on the proximal end and is in the middle of and in the 3BS wheat genome. Thus, the objectives of this project are to determine the gene order of , and , in a linkage block on chromosome 3BS and combining them in coupling. The linkage relationships were determined through analysis of a three-way cross between parental lines Arina, Alsen and Ocoroni86, containing the resistance genes , and respectively. A total of 1,600 F plants was screened, along with the parental lines, using KASPar genotyping technology via single-nucleotide polymorphism markers to identify the recombinant progeny. Phenotypic screening for SNB was performed on the entire F population. Knowing the positional order of these resistance genes will enable the development of a wheat line with three genes in coupling to provide durable and broad-spectrum resistance against three major diseases of wheat.

Improvement of resistance to Fusarium head blight (FHB) is a continuous challenge for durum wheat () breeding, where most germplasm are susceptible and low genetic variation is available for this trait. Research has focused on broadening the genetic basis by introducing alleles for FHB resistance from landraces and related species such as bread wheat (), cultivated emmer (), wild emmer () and Persian wheat () into durum wheat. We summarize and compare here QTL mapping studies carried out to date in tetraploid wheat. Thirteen QTL with small to moderate effects were repeatedly detected on 11 chromosomes with alleles improving FHB resistance deriving from relatives and from durum wheat itself. Comparison showed large overlaps of QTL positions with those identified in hexaploid wheat suggesting a common genetic basis for FHB resistance. FHB resistance breeding by allele introgression into durum wheat is feasible and QTL pyramiding in novel cultivars is a promising strategy for resistance breeding.

The use of multiparental populations for QTL discovery has been recently highlighted by different theoretical and experimental developments. Here, we explored the interest of French populations using heterogeneous genetic stocks of cultivated wheat, maintained in situ over 12 sites since 1984 with an outcrossing mating system. We studied one of these populations (Le Moulon, 48.4°N, 21°E), derived from 12 cycles of random crosses between 60 founders, selected to maximize genetic diversity. Outcrossing was allowed by the integration of a nuclear male sterility allele (, Probus donor) in the population. We analyzed 1,000 Single Seed Descent lines (SSD) derived from the 12th generation of cultivation. This population was genotyped using the 9 K i-select SNPs (Single Nucleotide Polymorphisms) array, covering the whole genome. Polymorphism and quality checks resulted in the selection of around 6,500 SNPs. First, the evolution of genetic diversity was explored through the comparison of SSD lines and the inferred initial population. The low population structure and the strong decay in linkage disequilibrium between SSD lines and the inferred initial population confirmed the efficiency of the 12 cycles of the random outcrossing in producing a highly diverse and recombined population. Two years of observations of population earliness under different environments were used to show the complementarity of association genetics, which allowed the detection of already known major genes, and evolutionary approach, which, lead to the discovery of two new minor effect QTLs.

Photoperiod (day-length) response, vernalization (response to extended periods of cold) and earliness per se () genes regulate flowering time in wheat. The vernalization and photoperiod response genes are relatively well studied. However, the role of genes is yet to be fully understood but the current assumption is that genes regulate flowering independent of vernalization and photoperiod. While some genes have been cloned in both and , none has been cloned in to date. The use of near isogenic lines (NILs) in both and has enabled effects to be studied in more detail and candidate genes have been proposed for effects in both species. loci are reported to be involved in fine tuning flowering time and are also responsible for controlling spikelet number and size hence could be manipulated to increase wheat yield. This mini review summarises our current understanding of and how manipulation of genes can be used in predictive wheat breeding.

The Special Session was sponsored by the OECD Co-operative Research Programme on Biological Resource Management for Sustainable Agricultural Systems, whose financial support made it possible for most of the invited speakers to participate in the Special Session.