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

Salsomaggiore Terme, Italy - 26/29 September, 2001

ISBN 88-900622-1-5

Poster Abstract

MAPPED MARKERS ASSOCIATED TO QUANTITATIVE TRAITS OF THE SPIKE IN DURUM WHEAT GERMPLASM

FIGLIUOLO G., POMARICO M.

Dipartimento di Biologia Difesa Biotecnologie Agro-Forestali, Università degli Studi della Basilicata, Potenza

figliuolo@unibas.it

germplasm, linkage, MAS, wheat

A sample of 56 durum wheat germplasm lines, extracted from a world core collection differentiated for traits component of yield, was analysed with a core of 61 RFLP probes distributed over the whole set of wheat linkage groups.

Multivariate (cluster) and univariate (ANOVA, t-test) analyses were carried out to identify the distribution of genetic variation and the associations between genetic markers and useful variation for quantitative traits of the spike. Three RFLP groups were detected by cluster analysis: Group I composed of lines highly diversified from different geographic origins, group II with lines mainly from the Eastern side and group III mainly from the Western side of the distribution area. The most genetically diversified lines (group I) had greater variation for all morphological quantitative traits.

Significant differences for number of nodes per spike was detected between RFLP group II and I. Six RFs were found associated (P<0.01) with at least one of these traits: number of nodes, number of kernels, kernel weight per spike and spike length. A consistent grouping for both quantitative spike traits and RFLPs was observed. Lines having high number of kernels per spike clustered together with either the whole set (293) of RFLP markers or only with the markers statistically associated using t-test (32 RF with P<0.05 or 6 RF with P<0.01). Linkage disequilibrium test was used to distinguish between marker associations due to linkage and marker associations due to selection and drift. The identification of genetic groups bearing differential patterns of variation for both QTLs and genetic markers, within durum wheat genepool, can promote the use in breeding programs of germplasm accessions conserved ex situ.