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

Verona, Italy - 24/27 September, 2003

ISBN 88-900622-4-X

Oral Communication Abstract - S2d

MARKER-ASSISTED SELECTION FOR VIRUS AND LOW TEMPERATURE TOLERANCE IN BARLEY

N. PECCHIONI**, E. FRANCIA*, D. BARABASCHI*, G. LAIDÓ*, F. REGGIANI*, B. TOTH***, V. SIP****, F. RIZZA*, G. DELOGU*

*) Istituto Sperimentale per la Cerealicoltura, Sezione di Fiorenzuola, Via San Protaso 302, 29017 Fiorenzuola d'Arda (PC)

**) Università degli Studi di Modena e Reggio Emilia, Facoltà di Agraria, Via J.F. Kennedy 17, 42100 Reggio Emilia

***) Agricultural Research Institute of the Hungarian Academy of Sciences, 2462 Martonvásár, Hungary

****) Research Institute of Crop Production, Prague-Ruzyne, Czech Republic

BaYMV, BYDV, MAS, barley, frost tolerance, STS markers

The soil-borne barley yellow mosaic virus (BaYMV), the aphid-borne barley yellow dwarf virus (BYDV) and the seed-borne fungus Pyrenophora graminea (leaf stripe) are the most serious diseases for the barley crop in Southern Europe environments, where mildew and other foliar diseases have a relatively small or not significant effect on yields. The development of barley cultivars resistant to the three diseases is thus an urgent objective of barley breeding for the area, in a context of increasing organic farming for cereals. Nevertheless, breeding for multiple diseases encounters several economical and technical problems, and cultivars resistant to the former diseases are not yet available. The bottlenecks of barley breeding for resistance to BYDV are the availability of sources of resistance, mainly based on semi-dominant Yd2 gene, and the labour-intensive inoculation test made with infected aphids. Availability of resistant germplasm and inoculation test are easier for BaYMV and, in relative terms, also for leaf stripe resistance. In this view, two schemes of marker-assisted selection (MAS) have been followed to develop high yielding advanced lines: an assisted pedigree by introducing the two virus resistances, and a "gene pyramiding" scheme to introduce four loci of resistance - two to leaf stripe, and one each to BYDV and BaYMV. STS and SSR markers have been selected for the aim and applied to segregating progenies together with phenotypic selection for agronomic traits.

Results of the two MAS processes are here presented, including yield performances of the advanced breeding lines.

Also frost tolerance is an important trait for winter barley breeding. Field selection for this trait is not always efficient since, especially in Southern Europe, severe winter frost is an erratic event. Recent advances in terms of cloned genes and of molecular markers in barley can give to molecular breeders the necessary informations for the development of new, simple PCR-based molecular markers that can be important tools to select quickly the frost tolerant genotypes. We report here the development of three PCR-based markers, two STS markers, derived from the WG644 and PSR637 RFLP probes, and one RAPD, OPA17, chosen for their location on chromosome 5H, where most important loci for frost tolerance had been previously mapped. In the 'Nure' x 'Tremois' barley map, based on a segregating population of doubled haploid lines, the PSR637, the WG644 STSs and the OPA17 RAPD were mapped on the long arm of chromosome 5H. The developed markers were also validated on a set of winter and spring barley genotypes with different levels of frost tolerance. The efficiency of the developed markers to separate the frost tolerant and susceptible genotypes was clear.