Simultaneous improvement of protein content and grain yield by index selection is possible but its efficiency largely depends on the weighting of the single traits. The genetic architecture of these indices is similar to that of the primary traits. Grain yield and protein content are of major importance in durum wheat breeding, but their negative correlation has hampered their simultaneous improvement. To account for this in wheat breeding, the grain protein deviation (GPD) and the protein yield were proposed as targets for selection. The aim of this work was to investigate the potential of different indices to simultaneously improve grain yield and protein content in durum wheat and to evaluate their genetic architecture towards genomics-assisted breeding. To this end, we investigated two different durum wheat panels comprising 159 and 189 genotypes, which were tested in multiple field locations across Europe and genotyped by a genotyping-by-sequencing approach. The phenotypic analyses revealed significant genetic variances for all traits and heritabilities of the phenotypic indices that were in a similar range as those of grain yield and protein content. The GPD showed a high and positive correlation with protein content, whereas protein yield was highly and positively correlated with grain yield. Thus, selecting for a high GPD would mainly increase the protein content whereas a selection based on protein yield would mainly improve grain yield, but a combination of both indices allows to balance this selection. The genome-wide association mapping revealed a complex genetic architecture for all traits with most QTL having small effects and being detected only in one germplasm set, thus limiting the potential of marker-assisted selection for trait improvement. By contrast, genome-wide prediction appeared promising but its performance strongly depends on the relatedness between training and prediction sets.

The efficiency of our anther culture protocol was tested with high‐ and low‐responding genotypes, ‘Svilena’ and ‘Berengar’, and 93 F1 winter wheat crosses in 2010 and 2011. Based on data for these genotypes, the effect of genotype influenced the number of embryo‐like structures, regenerated plantlets and green plantlets, while the number of albino plantlets was affected by genotype, year and environmental factors. Although genotype also influenced the production of green plantlets from breeding crosses, with green plantlets per 100 anthers ranging from 0.04 to 28.67, the average regeneration rate over all crosses was 5.3 green plantlets/100 anthers, which resulted in a total of 11 416 well‐rooted green plantlets. The survival rate of green plantlets following acclimatization was 97.21% in 2010 and 96.34% in 2011. In this study, the phenomenon of albinism and genotype dependency did not hinder the production of more than five thousand green plantlets each year. In our experiments, anther culture proved to be an efficient method in winter wheat breeding programmes with lower costs than alternative technologies.

Knowledge of quantitative genetic parameters is crucial in aiiocafing resources for different steps of multistage selection programs. The main objective of the present study was to investigate the magnitude of variance of general combining ability (GCA) and specific combining ability (SCA) effects and their interaction with environments in wheat {Triticum aestivum L.). We used four data sets (Exp.

The use of multi‐angle laser light scattering (MALLS) in conjunction with asymmetrical flow field‐flow fractionation (A‐FFFF) was investigated for the determination of the molecular weight distribution (MWD) of wheat proteins. The wheat flour proteins were dissolved by sonication in 0.1M sodium phosphate (pH 6.9) containing 2% SDS. The results presented make it evident that efficient separation and size characterization of monomeric (M < 105 g/mol) and polymeric protein (105 ≤ M < 108 g/mol) wheat proteins can be achieved with A‐FFFF/MALLS/UV in a single run. Therefore, this method appears to be able to detect significant modifications of MWD of wheat protein, whatever the factor inducing these alterations (i.e., genetic or environmental) and whatever the nature of these alterations (i.e., monomeric‐to‐polymeric ratio or MWD of polymeric protein). In the present study, we have indeed demonstrated that the MWD of wheat proteins can be altered from one cultivar to another in three main ways: by changing the relative amounts of monomeric and polymeric proteins, by changing the MWD of polymeric protein, and then by changing both the monomeric‐to‐polymeric ratio and the MWD of polymeric protein.

No abstract

An inbred genotype of cultivated rye was found that produces unreduced gametes in a very regular fashion. In the cross progeny of this line with another inbred line, which did not show unreduced gametes, the inheritance of this phenomenon was studied. The formation of unreduced gametes appears to be a recessive trait controlled by more than one gene. Chiasma frequency in 4n PMCs is exactly twice that in 2n PMCs. In first metaphase of 4n PMCs only bivalents (no multivalents) were seen. The possible mechanism leading to unreduced gametes and its evolutionary implications are discussed. Key words: rye, unreduced gametes, polyploidy, genetic control, chiasma frequency.

LEIN, V., and LELLEY, T. 1987. A separate control for frequency and within-bivalent distribution of chiasmata in rye (Secale cereale L.). Genome, 29: 4 19-424. Six genetically different inbred genotypes of spring-type rye Secale cereale with differences in the average number and in the positional distribution of chiasmata were used in this study. The line with the lowest chiasma frequency was chosen as the female parent and crossed with the other five lines. Parental, F, , and F2 data were collected on chiasma number and on chiasma distribution between and within bivalents. Evidence for a polygenic control of both phenomena was found. Chiasma distribution between bivalents within pollen mother cells obviously follows a binomial distribution. This is effected by a mechanism that prevents the formation of a second chiasma on a chromosome arm as long as chromosome arms without chiasma remain; i.e., with 14 chiasmata seven ring bivalents will generally be formed. This mechanism causes a very strong negative correlation between frequency and between-cell variance of chiasmata. The number of chiasmata is independent of their position within the bivalents. A very close correlation between the number of pollen mother cells without univalents and the number of fertile pollen grains was found.Key words: inbred rye, genetic control, chiasma frequency, chiasma distribution, heterosis.LEIN, V., et LELLEY, T. 1987. A separate control for frequency and within-bivalent distribution of chiasmata in rye (Secale cereale L.). Genome, 29 : 4.19-424. Six genotypes consanguins gknktiquement diffkrents de seigle de printemps, Secale cereale, qui prksentent des diffkrences quant au nombre moyen de chiasmata et a la distribution de leur position, ont kt6 utilisks pour la prksente etude. La lignke dont la frkquence des chiasmata ktait la plus faible a kt6 choisie comme parent femelle et croiske avec les cinq autres lignkes. Les donnkes relatives au nombre de chiasmata et a leur distribution entre et a I'intkrieur des bivalents ont kt6 prises chez les parents et chez les descendances F1 et F2. L'kvidence qu'il existe un contr6le polygknique pour les deux phknomenes a kt6 trouvke. La distribution des chiasmata entre bivalents chez les cellules-meres des grains de pollen s'opere selon une distribution binomiale. Ceci s'effectue par un mkcanisme qui empeche la formation d'un second chiasma sur un meme bras chromosomique aussi longtemps qu'il existe des bras de chromosomes sans chiasma; ainsi, 14 chiasmata conduiront gknkralement a la formation de sept bivalents en anneaux. Ce mkcanisme cause une corrklation tres fortement negative entre la frkquence des chiasmata et la variance entre cellules. Le nombre de chiasmata est indkpendant de la position de ces derniers a l'intkrieur des bivalents. Une tres ktroite corrklation a kt6 trouvke, cependant, entre le nombre de cellules-meres de pollen qui ne possedent pas d'univalents et le nombre de grains de pollen fertiles.

Pionero INIA es la primera variedad de trigo doble propósito liberado por el Programa Nacional de Trigo del INIA Carillanca. Es una variedad de invierno (Triticum aestivum L.) producto de la selección de germoplasma recibido de la Empresa Saaten Union Research de Francia. Mostró excelente adaptabilidad para siembras tempranas, en zonas de inviernos largos y primaveras húmedas. La altura promedio de planta adulta alcanza los 90 cm, siendo clasificado como una variedad de trigo enano a semi enano. El rendimiento promedio, en diferentes localidades y varios años de evaluación, fue significativamente superior al testigo Kumpa INIA, destacándose por su resistencia a enfermedades y tipo agronómico. Sus características de calidad molinera y de almidón permiten utilizarlo en la industria galletera, ganadera y acuícola.