Proceedings of the XLVI Italian Society of Agricultural Genetics - SIGA Annual Congress

Giardini Naxos, Italy - 18/21 September, 2002

ISBN 88-900622-3-1

Poster Abstract - 4.09

Transformation of Italian durum wheat cultivars with High Molecular Weight Glutenin Subunit genes from the D genome

Gadaleta a.*, Blechl A.**, Nguyen s.**

*) Dipartimento di Biologia e Chimica Agro-Forestale ed Ambientale, Università degli Studi, Bari

**) USDA-ARS Western Regional Research Center, Albany, CA 94710-1105 USA

durum wheat, transformation particle gun, HMW-GS

Durum wheat (Triticum turgidum L. var. durum) is traditionally used for the production of numerous types of pasta, and significant amounts are also used for bread-making, particularly in southern Italy. Durum wheat is a tetraploid cereal (AABB) and does not have the D genome found in bread wheats. Generally durum wheat is considered unsuitable for bread production because it lacks gluten strength. The flour properties of wheat are strongly determined by the gluten protein fraction corresponding to the grain storage proteins. Storage proteins (gliadins and glutenins) have significant effects on baking quality, and both qualitative and quantitative characteristics of these proteins must be considered when attempting to explain the quality variations observed among different wheats. Therefore, breeding efforts have focused on the manipulation of storage protein composition. Glutenin proteins are especially important in determining flour end-use properties because of their unique ability to form the networks that are the frameworks of viscoelastic doughs. Recent studies indicated that the relative proportion of High Molecular Weight Glutenin Subunits (HMW-GS) can be predictive of bread quality. The research reported here centers on the particular glutenin subunits Dx5 and Dy10, which are encoded by chromosome 1D, and whose presence is positively correlated with higher dough strength. In order to improve durum wheat’s suitability for technological properties, four cultivars very commonly grown in the Mediterranean areas (Latino, Svevo, Creso and Varrano), were co-transformed, via particle bombardment of cultured immature embryos, with the two wheat genes that encode the Dx5 and Dy10 glutenin subunits, and a third plasmid containing the bar gene as a selectable marker. Protein gel analyses of T1 generation seed extracts show expression of one or both glutenin genes in four different transformed durum wheat plants.