Characterization of a set of common wheat–Hordeum chilense chromosome 7Hch introgression lines and its potential use in research on grain quality traits

Chromosome 7Hch from Hordeum chilense has potential for improving seed carotenoid content in wheat as it carries a Phytoene synthase 1 (Psy1) gene, which has a major role in this trait. Structural changes in chromosome 7Hch were obtained in common wheat background by crossing the wheat disomic substitution line 7Hch(7D) with a disomic addition line carrying chromosome 2Cc from Aegilops cylindrica in common wheat cv. ‘Chinese Spring’. Rearranged 7Hch chromosomes were cytologically characterized by FISH. A set of 24 molecular markers and the Psy1 gene were used to identify the H. chilense chromosome segments involved in the introgressions. Six structural rearrangements of chromosome 7Hch were identified. They included three homozygous wheat–H. chilense centromeric translocations, one involving the 7HchS arm (T-7HchS·A/B) and two involving the 7HchL arm (T1-7HchL·A/B and T2-7HchL·A/B). In addition, one 7HchS arm deletion, one 7HchL·7HchL isochromosome and one 7HchS telosome were obtained in hemizygous condition. These genetic stocks will be useful for studying the effect of chromosome 7Hch on wheat flour colour.M.G. Mattera received a fellowship from the Ministerio de Economía, Industria y Competitividad (BES-2012-055961). This research was funded by grant AGL2014-53195R from the Ministerio de Economía, Industria y Competitividad, Spain (MINECO), with cofinancing from the European Regional Development Fund.Peer reviewe

Lutein ester profile in wheat and tritordeum can be modulated by temperature: Evidences for regioselectivity and fatty acid preferential of enzymes encoded by genes on chromosomes 7D and 7Hch

The increase of lutein retention through the food chain is desirable for wheat breeding. Lutein esters are more stable than free lutein during post-harvest storage and two loci on chromosomes 7D and 7Hch are important for esterification. We investigated the effect of temperature during grain filling on carotenoid accumulation and lutein ester profile including fatty acid selectivity (palmitic vs. linoleic) and regioselectivity (esterification at positions 3 vs. 3′). Three different temperature regimes were assayed (controlled, semi-controlled and non-controlled). Lutein esters were more stable than free carotenoids in vivo and the enzymes encoded by chromosomes 7Hch and 7D are complementary. Indeed, they show differential preferences for the fatty acid (palmitic and linoleic, respectively) and regioselectivity (3 and 3′, respectively). Besides, H. chilense has additional genes for esterification. Finally, the increase of temperature favoured the accumulation of lutein esters with linoleic acid and the synthesis of regioisomers at position 3′.This research was funded by Grant AGL2014-53195R, from Ministerio de Economía y Competitividad, Spain (MINECO) including FEDER funding. D.H.-M. is a member of CaRed Network, funded by MINECO, Spain, (BIO-2015-71703-REDT). M.G.M. was recipient of a fellowship from MINECO (BES-2012-055961).Peer reviewe

Carotenoid esterification in a collection of Hordeum chilense

Workshop "Caroteno¡ds in Food, Nutrition ond Health", 4th Working Groups and 5th Management Committee Meetings (EUROCAROTEN), Valencia (Spain) 23_25 October, 2018.Tritordeum, the amphiploid derived from the cross between Hordeum chilense Roem. et Schultz' and durum wheat, is being successfully commercialized due to its differential characteristics compared to durum and common wheat. Tritordeum-derived products exhibit a distinctive golden colour due to the presence of lutein in the endosperm. Tritordeum grains show higher carotenoid content than their durum wheat parents due to H. chilense genes' Besides, a high proportion of these carotenoids are esterified with fatty acids in tritordeum. only palmitic and linoleic acids are involved in lutein esterification in tritordeum but palmitate esters are more abundant than linoleate ones. Carotenoid esters are more stable during storage and processing. Thus, a high esterification proportion may be an interesting trait for tr¡tordeum breeding since it would allow increasing carotenoid retention in the food chain. Moreover, carotenoid esterification has been suggested as a mechanism enhancing carotenoid production and accumulation in plant cells. The absence of lutein esters in the endosperm of durum wheat indicates that lutein esterification in tritordeum is controlled by H. chilense genome

Diversidad genética para esterificación de luteína en Hordeum chilense

Trabajo presentado en el VIII Congreso de Mejora Genética de Plantas, celebrado en Vitoria del 12 al 14 de julio de 2016.Los granos de trigo duro y tritórdeo se caracterizan por la presencia de carotenoides que les confieren un característico color amarillo. Las líneas de tritórdeo tienen un contenido de carotenoides muy superior al de sus trigos duros parentales (Atienza et al. 2007). Además, los tritórdeos presentan un perfil de carotenoides distintivo, ya que parte importante de la luteína se encuentra esterificada con ácidos grasos (palmítico y linoléico) debido al genoma de Hordeum chilense Roem. et Schultz. (Mellado-Ortega y Hornero-Ménclez 2015). La csterificación incrementa la estabilidad de los carotenoides durante el almacenamiento (Mellado-Ortega y Hornero Méndez 2016), por lo que es un carácter a tener en cuenta. Estudios recientes con líneas ele sustitución de H. chilense en trigo harinero han demostrado la existencia de genes para esterificación en los cromosomas 7Hch y 70 (Mattera et al. 2015). El objetivo de este trabajo es estudiar la diversidad genética existente en H. chilense para el perfil de carotenoicles. como paso previo para el desarrollo de estudios de GWAS (Genome Wide Association Mapping) en relación con el contenido en carotenoides y su perfil de esterificación.Investigación financiada por AGL2014-53195-R (cofinanciado por PEDER). M.G.M agradece la concesión de una beca FPI (BES-2012-055961). D.H.M es miembro de la red temática CaRed, financiada por MINECO (BI02015-71703-REDT).N

Carotenoid accumulation patterns and lutein esterification process during grain development

Trabajo presentado en el I Simposio Español de Fisiología y Mejora de Cereales, celebrado en Zaragoza el 9 y 10 de abril de 2018.Hexaploid tritordeum (×Tritordeum martini A. Pujadas (Pujadas 2016) is the amphiploid derived from the cross between Hordeum chilense and durum wheat (Martín and Sánchez-Monge 1982). This new crop has higher carotenoid content than durum wheat (Atienza et al.2007) and a distinctive profile of lutein esterification with fatty acids.Carotenoid esters increase carotenoid retention during storage of grains (Mellado-Ortega and Hornero-Méndez 2016; Mellado-Ortega et al. 2015) and flour (Mellado-Ortega and Hornero-Méndez 2017) and thus it is a trait of interest for cereal breeding.Research funded by Grant AGL2014-53195R, from Ministerio de Economía y Competitividad, Spain (MINECO) including FEDER funding. M.G.M. was recipient of FPI (BES-2012-055961). D.H.-H. is a member of CaRed Network, funded by MINECO (BIO2015-71703-REDT). S.G.A. is a member of FiRCMe Network, funded by MINECO (AGL2016-81855-REDT)

Cytological and molecular characterization of wheat-Hordeum chilense chromosome 7Hch introgression lines

Chromosome 7Hch of Hordeum chilense carries the Phytoene synthase 1 (Psy1) gene encoding the first step in the carotenoid biosynthetic pathway. As such it can be used in the improvement of seed carotenoid content in wheat. Four introgressions of chromosome 7Hch into wheat have been characterized by in situ hybridization of labeled DNA probes and by several sets of DNA markers. Chromosome-specific SSR were used for the identification of wheat chromosomes. Besides 113 conserved orthologous set (COS) markers were tested for homoeologous group 7, of which 97 amplified in H. chilense and 32 were polymorphic between H. chilense and wheat, and 28 expressed sequence tag (EST) barley markers previously allocated to chromosome 7. A total of 60 markers (32 COS and 28 EST) were allocated to chromosome 7Hch with 28 assigned to 7HchS and 22 to 7HchL. A combination of in situ probing and marker genotyping have shown that among the four introgressions there was a substitution line 7Hch (7D), a ditelosomic addition line for the long arm of 7Hch and two homozygous centric translocations 7HchS·2DS and 7HchS·5AL. The Psy1 gene was localized on the short arm of 7Hch. The positions of markers from the international barley consortium map (IBSC2012) were determined and the comparative arm location between H. chilense and H. vulgare is discussed. The genetic stocks characterized here include new wheat-H. chilense recombinations useful for genetic studies and with a potential for breeding.M. G. Mattera was recipient of a fellowship from Ministerio de Economía y Competitividad (BES-2012-055961). The authors thank Prof. Tsujimoto (Tottori University, Japan), for providing barley EST primer sequences. This research was funded by Grant AGL2011-24399, from Ministerio de Economía y Competitividad including FEDER funding.Peer reviewe

Potential of chromosomes 7D and 7Hch for the enhancement of lutein esterification in wheat

Trabajo presentado en el 8th international Congress on Pigments in Food (Colored Food for Health Benefits), celebrado en Cluj-Napoca (Rumanía) del 28 de junio al 1 de julio de 2016.Endosperm colour of wheat grains is an important quality criterion in breeding programs (YPC, yellow pigment content). YPC is mainly due to carotenoids. Durum wheat is selected for high YPC for pasta production (Ficco et al. 2014). On the contrary, white flour is usually preferred for bread-making although new yellowish bread types are being producing from einkorn or tritordeum (xTritordeum Aschers. et Graeb .) (reviewed by Rodríguez-Suárez et al. 2010). Lutein is the main carotenoid present in the endosperm of wheat (Digesú et al. 2009) where the gen Phytoene synthase 1 (Psy 1) plays the main role in the determination of seed carotenoid content in grains (Ficco et al. 2014; Rodríguez-Suárez et al.2014). The development of wheat-alien translocations has allowed the enhancement of carotenoid content in durum wheat (Ceoloni et al. 2014). In this work we have investigated the effect of chromosomes 5Hch and 7Hch from H. chilense on total carotenoid content and lutein esterification profile.This research was supported by Grants AGL2011-24399 and AGL2010-14850 from the Ministerio de Economía y Competitividad (MINECO), including FEDER funding. MGM was recipient of a predoctoral grant BES-2012-055961, also from MINECO). D. H. M. is a member of CaRed, funded by Mineco (BIO2015-71703-REDT).N

Lutein esterification in wheat endosperm is controlled by the homoeologous group 7, and is increased by the simultaneous presence of chromosomes 7D and 7Hch from Hordeum chilense

The high carotenoid content in tritordeum (×Tritordeum Ascherson et Graebner) grains is derived from its wild parent, Hordeum chilense Roem. et Schulz. Phytoene synthase 1 (Psy1) is located on chromosome 7HchS and plays a major role in this trait. This study investigates the impact of the introgression of chromosome 7Hch into common wheat background on carotenoid composition, including xanthophylls esterified with fatty acids (monoesters and diesters). All of the genetic stocks carrying Psy1 from H. chilense increased their carotenoid content relative to common wheat. In addition, significant changes in the carotenoid profile were detected in different genetic stocks. The most relevant was the increase in content of lutein diesters when both 7Hch and 7D were present, which indicates the existence of genes involved in the esterification of xanthophylls in both chromosomes. Furthermore, our results suggest that 7Hch genes preferentially esterify lutein with palmitic acid, whereas 7D is either indifferent to the fatty acid or it prefers linoleic acid for lutein esterification. The involvement and complementarity of 7Hch and 7D are highly significant considering the scarcity of previous results on lutein esterification in wheat.M. G. Mattera was recipient of a fellowship from Ministerio de Economía y Competitividad (BES-2012-055961). This research was funded by Grant AGL2011-24399, from Ministerio de Economía y Competitividad includingFEDER funding. D. H. M. is a member of the IBERCAROT Network, funded by CYTED (ref. 112RT0445).Peer Reviewe

Effect of chromosome 7Hch from Hordeum chilense Roem. Et Schultz. On carotenoid content and lutein esterification in common wheat

Trabajo presentado en la EUCARPIA Cereals Section - ITMI Joint Conference (Cereals for Food, Feed and Fuel – Challenge for Global Improvement), celebrada en Wernigerode (Alemania) del 29 de junio al 4 de julio de 2014.Colour is an important quality criterion for most wheat end-use products. Yellow colour has become an important selection criterion in durum wheat (Triticum turgidum spp. durum, 2n=4x=28, AABB) due to its importance for the production in pasta. On the contrary, white flour is traditionally preferred by consumers for the bread-making using common wheat (T. aestivum L. 2n=6x=42, AABBDD). However, lutein also contributes in part to the yellow colour of yellow alkaline noodles which is promoting the development of high lutein materials in Australia. Similarly, new end-use products using either einkorn (T. monoccocum L. ssp. monococcum L., 2n=2x=14, AA), or the new cereal tritordeum (× Tritordeum Ascherson et Graebner, 2x=6x=42, AABBHchHch) are partly yellow due to the high carotenoid content of these species compared to common wheat. Hexaploid tritordeum is the amphiploid derived from the cross between the wild barley (Hordeum chilense Roem et Schultz., 2n=2x=14) and durum wheat. The addition of chromosome 7Hch to common wheat results in the increase of yellow pigment content. However, the effect of this chromosome in wheat has not been tested in euploid combinations. In this work, we have used five genotypes of common wheat with either translocations or substitutions involving the chromosome 7Hch. These lines were characterized using molecular markers and further confirmed using FISH (fluorescent in-situ hybridization). These lines were analyzed for carotenoid content at harvest. Chromosome substitution lines of H. chilense into ‘Chinese Spring’ wheat background available from other sources were used as controls along with durum wheat ‘Kofa’ and tritordeum ‘HT621’. All the lines carrying Psy1 from H. chilense had a higher seed carotenoid content (mainly lutein) than the wheat control. However, the profile of lutein esterification differed among the lines and it depended on the interaction with the wheat genes.This research was supported by Grants AGL2011-24399 and AGL2010-14850 from the Ministerio de Economía y Competitividad (MINECO), including FEDER funding. MGM was recipient of a predoctoral grant BES-2012-055961, also from MINECO).N

Development of DArTseq markers in Hordeum chilense for genetic studies

Trabajo presentado en el 8th International Triticeae Symposium y la 13th Gatersleben Research Conference, celebrados en Wernigerode/Gatersleben (Alemania) del 12 al 16 de junio de 2017.Hordeum chilen e Roem. et chultz. is a wild barley species with potential in cereal breeding. lndeed hexaploid tritordeum, which is being commercialized at present dueto its differential attribute compared to common wheat, is the amphiploid derived from the cross between H chilen e and durum wheat (Martin and Sánchez-Monge 1982). Besides, H chilense has also potential in wheat breeding for important traits such as seed carotenoid content (Mattera et al. 20lSa· Mattera et al. 2015b). Gene~c studies ,ha ve allow~d the identification and mapping of candidate genes for quality traits ~o~guez-Suar.ez and Atlenza 2012; Rodríguez-Suárez and Atienza 2014) but the diversity wlthin the specles .has not been fully exploited. In this context, the availability of highthro~ put genotypmg platform~ constitutes an important tool for genetic studies in H chilense. In this .work, both ~heRIL prev10usly used for mapping (Rodríguez-Suárez et al 2012) anda collect10n of H. chzlense were genotyped using DArTse m k · · de eloped as a previous step for GW AS enome- q. ar ers .. A .new genetic map .~ been coUection for carotenoid profile and agro-mo(g holo . Wld~ assoc1atwn sean) analysts m the structure with the existence oftwo groups el rp 1 d~~ tralts. H chilense revealed a population to provide new insights on the genetic contr~arfy. 1 erentiate~. GWAS analyses are expected 0 Important tralts.N