Seeking stable traits to characterize the root system architecture. Study on 60 species located at two sites in natura.

Background And Aims: In several disciplines, identifying relevant root traits to characterize the root system architecture of species or genotypes is a crucial step. To address this question, we analysed the inter-specific variations of root architectural traits in two contrasting environments.

Methods: We sampled 60 species in natura, at two sites, each presenting homogeneous soil conditions.

Simulating genotypic variation of fruit quality in an advanced peach x Prunus davidiana cross.

Ecophysiological models are increasingly expected to describe genotypic variation within breeding populations. Accordingly, the ability of an ecophysiological model of peach to explain variation in fruit quality among 100 genotypes of a second backcross progeny derived from a clone of wild peach (Prunus davidiana) crossed with two commercial nectarine (Prunus persica) varieties was explored. Experimental measurements were carried out to calibrate the model for each genotype.

Analysing the genetic control of peach fruit quality through an ecophysiological model combined with a QTL approach.

Ecophysiological models are increasingly expected to include genetic information via genotype-dependent parameters. These parameters could be considered as quantitative traits and submitted to analysis. A pre-existing ecophysiological model of fruit quality was used and the distribution of the genotypic parameters in a second backcross population derived from a clone of a wild peach (Prunus davidiana) and commercial nectarine varieties (P.

Analogues of virus resistance genes map to QTLs for resistance to sharka disease in Prunus davidiana.

Plum pox virus (PPV), the causative agent of sharka disease in Prunoideae, is one of the most serious problems affecting stone fruit production in Europe and America. Resistance to PPV was previously described in a Prunus davidiana clone, P1908, and introduced into peach (Prunus persica) genotypes. Genetic resistance to PPV displays a complex pattern of quantitative inheritance.

QTL analysis of quality traits in an advanced backcross between Prunus persica cultivars and the wild relative species P. davidiana.

Genetic control of the different attributes involved in peach quality has been investigated in an advanced backcross population derived from a cross between Prunus davidiana clone P1908, a wild parent with poor agronomic performance, and a commercial variety, Summergrand. A total of 24 physical and biochemical traits were investigated. Quantitative trait loci (QTLs) were detected for all the traits studied.