Resistance to Melampsora larici-epitea leaf rust in Salix : analyses of quantitative trait loci

• Quantitative resistance of Salix to Melampsora larici--epitea leaf rust was studied in 2 Salix mapping populations. One population was a backcross between a S, schwerinii x S. viminalis hybrid and S. viminalis, and the other was all F-2 population between S. viminalis and S. dasyclados. A leaf disc bioassay was used to study the components of quantitative resistance (latent period, uredinia number, and uredinia size) to 3 isolates of the leaf rust. The analysis of quantitative trait loci (QTLs) revealed 9 genomic regions in the backcross population and 7 genomic regions in the F-2 population that were important for rust resistance, with QTLs explaining 8-26% of the phenotypic variation. An important genomic region was identified for the backcross population in linkage group 2, where QTLs were identified for all resistance components for 2 of the rust isolates. Four of the QTLs had overlapping mapping intervals, demonstrating a common genetic background for latent period, uredinia diameter, and uredinia number. QTLs specific to some rust isolates and to some resistance components were also found, indicating a combination of common and specific mechanisms involved in the various resistance components. Breeding implications in relation to these findings are discussed.

Ämnesord

NATURVETENSKAP  -- Biologi (hsv//swe)

NATURAL SCIENCES  -- Biological Sciences (hsv//eng)

Nyckelord

leaf disc inoculation

Melampsora larici-epitea

QTL mapping

quantitative resistance

Salix dasyclados

Salix schwerinii

Salix viminalis

short-rotation coppice

hybrid poplars

populina

willow

gene

aflp

components

mixtures

races

spp.

Biology

Biologi

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)