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Significant results


Barley breeding achievements: from Arda to the new varieties
Arda (taken from the name of the stream that runs through Fiorenzuola) is a two-rows winter variety of barley released in 1986 with a high yield potential, high yield stability and improved harvest index (HI). Arda
was the first two-row winter variety yielding more than six-row varieties in Italian environments.
After Arda, the breeding programs have been orientated towards the selection of new genotypes able to cope with the adverse environmental conditions. The new barley cultivars possessed improved tolerance to cold, and drought stress and carried genes conferring resistance to virosis (Barley Yellow Dwarf Virus (BYDV) and Barley Yellow Mosaic Virus (BaYMV), powdery mildew and leaf stripe. A parallel breeding work was dedicated to the development of new malting cultivars and naked barley for functional foods. A successful breeding program was also established in triticale and oat and new cultivars have been released.

Barley genetics
A barley genetic map was developed on the segregating population derived from the cross “Nure x Tremois” and was used to localise genes responsible for abiotic stress resistance, plant development and flowering. A relevant result was the identification of a region on chromosome 5H responsible for most of the genetic variation observed in the barley for adaptation to cold and drought conditions. The same population was also exploited for the cloning of the HvCEN gene, the determinant of the Earliness per se 2 (EPS2) locus on chromosome 2H involved in the regulation of barley flowering time. Ad hoc barley mapping populations (e.g. Mirco x Thibaut) were developed to identify genetic loci involved in barley resistance to the leaf stripe pathogen Pyrenophora graminea. An high resolution genetic mapping population coupled with a positional cloning approach allowed the map-based cloning of the Rdg2a leaf stripe barley resistance gene, a CC-NB-LRR resistance gene.

Gene cloning and characterization
The capacity of a plant to resist and be productive in adverse situations (e.g. presence of a pathogen, or a physical stress) is linked to the presence and expression of specific genes. A number of genes that are involved in mechanisms of plant-pathogen interaction, cold and drought resistance have been cloned. Among those cloned are regulatory genes (transcription factors) able to activate gene pools that are directly involved in the complex metabolic pathways of stress tolerance in plants. In addition, genes involved in the expression of various agronomic and quality traits (e.g. germination, malting quality) have also been identified. Several albina and xantha mutants have been characterized at transcriptional level highlighting the role of the chloroplast in the acclimation to low temperatures.
Genes involved in the control of the ubiquitination process in response to abiotic stresses have been characterized and the interactome of the corrisponding proteins have been riconstrucded using a yeast-two-hybrid system.
Through the years a number of molecular techniques have been used for gene cloning and gene expression analysis in the laboratory of the Centre: from differential screening of cDNA library and northern analysis to microarray. Mutants, transgenic plants and RNAi have been used to characterized the isolated genes and their role in the determination of the plant phenotype.

Quality traceability and security
The term molecular traceability indicates genomic, proteomic, and metabolomic methods capable of characterising an agricultural production chain or food product in terms of safety, quality, geographic origin, nutritional value and authenticity. Molecular fingerprinting can be applied at all levels of the food production chain from the characterization of the genetic diversity to the traceability of raw materials through transformation, packaging and distribution.
At the Centre new approaches of molecular traceability have been developed based on techniques of DNA profiling for the identification and quantification of plant, animal and microbial species (from allergenic plants to micotoxin producing fungi) as well as for the identification of conventional and transgenic varieties in raw materials, food products and feed stuffs.

Functional foods and malting quality
Barley and oats are ideal ingredients for functional foods considering that they have a high content of β-glucans (soluble fibre that composes the cell wall of the endosperm). β-glucans have the property of forming highly viscous solutions in the intestines and thus reducing plasma-cholesterol and influencing the biosynthesis of endogenous cholesterol, lowering the level of postprandial glucose and the consequent insulin response, enabling the selection of intestinal flora thanks to the fermenting activity, and slowing down gastric emptying giving a sense of satiety.
To produce barley flours enriched in β-glucans, grain micronization and air classification of the flour were used, and a method to predict the relationship between the yield of the enriched flour and its β-glucan content was developed. Enriched flour fractions with 11-15% β-glucans were obtained, with a good flour yield (about 30%). When barley flour is included in the dough the overall quality of bread slightly worsened. However, positive consequences on glycaemia were obtained with a reduction of the glycaemic index.
In contrast, β-glucans are unfavourable for beer production. Elevated levels of β-glucans reduce the malting quality, and makes problematic the filtering capacity of beer. The degradation of β-glucans in the kernel during germination has been studied and barley types that maintain a low level of β-glucans in malt have been selected.
A theoretical framework for β-glucan degradation during barley malting has been studied and it was shown that the kinetics of β-glucan degradation during malting can be explained according to an anomalous evolution of the reverse quasi-steady-state approximation (rQSSA) for enzymatic reactions.
A discriminant function combining Hot Water Extract, wort viscosity and acrospire growth was developed to discriminate malting quality for improving the efficiency of quality selection in breeding programmes for malting barley. This function provides a combined quality score for each genotype which is more stable in respect of the environment than each single parameter. This score, based on a minimal core of parameters, provides an objective scale to rank genotypes for malting quality. Hence, it represents an optimized criterion for basic selection of malting quality and also to identify the genotypes of highest ranking in quality.

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The Genomics Research Centre holds a collection of more than one hundred barley mutants.

Our contacts

Genomics Research Centre
Via S. Protaso, 302
29017 Fiorenzuola d'Arda (PC) - ITALY
Phone:
+39 0523 983758
Fax:
+39 0523 983750
E-mail:
gpg@entecra.it
How to find us

We thank Renzo Alberici, Donata Pagani and Gianni Tacconi for setting up the picture collection.