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

Verona, Italy - 24/27 September, 2003

ISBN 88-900622-4-X

Poster Abstract - 2.41

A DURUM WHEAT LINE PRODUCED BY CHROMOSOME ENGINEERING WITH NOVEL ALIEN TRAITS AND GREAT POTENTIAL FOR VARIETAL DEVELOPMENT

A. GENNARO*, P. FORTE*, G. M. BORRELLI**, M. G. D’EGIDIO***, P. DE VITA**^,****, S. RAVAGLIA*****, C. CEOLONI*

*) Dept. of Agrobiology and Agrochemistry, University of Tuscia, 01100 Viterbo, Italy

**) Experimental Institute for Cereal Research, Section of Foggia, 71100 Foggia, Italy

***) Experimental Institute for Cereal Research, 00191 Rome, Italy

****) Present address: ENEA - C.R. Trisaia, 75026 Rotondella, Matera, Italy

*****) S.I.S. – Società Italiana Sementi, 40068 S. Lazzaro di Savena, Bologna, Italy

Triticum durum, Thinopyrum ponticum, leaf-rust resistance, yellow pigment, alien gene transfer

Two genes of breeding value, i.e. Lr19 (leaf-rust resistance) and Yp (yellow pigmentation), closely linked on the 7AgL chromosome arm of the perennial wheatgrass species Thinopyrum ponticum, have been transferred into durum wheat by chromosome engineering. Several 7AL-7AgL recombinant lines were obtained which, as shown by physical and genetic mapping, incorporated alien segments of different size and gene content. Preliminary assessments of relevant agronomic and quality traits have been carried out on those possessing minimal alien chromatin amounts still including the target genes. Advanced selections from the cross of line R5-2-10, harbouring Lr19+Yp in a distal segment spanning 23% of the total arm length, with the well-adapted but leaf-rust susceptible variety Simeto, were tested during the 2001-2002 seasons. Compared to Simeto, the significantly enhancing effect of Yp gene on yellow pigmentation, already evident in early tests of whole-meal carotenoid pigments of such materials, was confirmed by evaluations of semolina colour parameters. No detrimental effects specifically ascribable to the presence of the alien segment were detected for other relevant grain and semolina traits. As to yield, in spite of non significant differences observed as a whole in both years, yet considerable increments with respect to the control were exerted by most R5-2-10 derivatives in the 2001 season, characterized by a heavy leaf-rust epidemic. Comparable or somewhat reduced productions, depending on the lines, resulted from virtually absent leaf-rust pressure (2002 season). The overall characteristics of some R5-2-10 advanced selections make them highly promising candidates for development of novel varietal germplasm, with added quality and nutritional value, able to respond to traditional agricultural systems, but also to meet more recent concerns on environmental sustainability.