Eugenia Martin

New genetic maps for globe artichoke and wild cardoon and their alignment with an SSR-based consensus map

An F1 mapping population was bred by crossing an accession of wild cardoon with a single Argentinian globe artichoke plant of the variety Estrella del Sur FCA with a view to generating new Cynara cardunculus linkage maps. Genotyping was conducting using a set of 553 SRAP, SSR, AFLP and SNP markers. The 1,465.5 cM map based on the segregation of alleles present in the wild cardoon parent comprised 214 loci distributed across 16 linkage groups (LGs), while the 910.1 cM globe artichoke-based map featured 141 loci falling into 12 LGs covering the total length. Three of the morphological traits (head spininess, leaf spininess and head color) for which the parents contrasted were inherited monogenically, and the genes conditioning them were mapped. A set of 48 co-dominant loci was used to align the LGs with those derived from a reference SSR-based consensus map of the species.

Response of Productive and Morphovegetative Traits of Globe Artichoke (Cynara cardunculus var. scolymus) to Mass Selection and Estimation of their Heritability

There have been few reports on genetic parameters or artificial selection for growth traits in globe artichoke (Cynara cardunculus var. scolymus), the study of the effect of one cycle of mass selection and realized heritability estimates would be valuable for planning breeding strategies in this species. A C0 segregating population was formed from the cross of two contrasting seed-grown cultivars, Imperial Star and Estrella del Sur FCA. Selected plants for productive traits were intercrossed to produce a C1 population. The C1 population along with the C0 population, both parents and the F1 were evaluated obtaining the response to selection and estimating realized heritability. Mass selection for increased yield and precocity was particularly successful, where for the first trait realized heritability reached 0.71 and 0.60 for the second one. For most traits, the observed values for realized heritability in the experiment (0.75, 0.61 and 0.52 for weight of the main head, marketable yield and length of the main head, respectively) indicate that a substantial part of the observed phenotypic variance is of additive nature. Therefore, in general, selection for these traits in seed-grown globe artichoke populations will be effective.

Comparison of morphological and molecular data for pea (Pisum sativum) in low and high yielding environments.

Abstract Genotypes by year interactions are considered to be among the major factors limiting response to selection. The objectives of this study were to estimate the heritability via variance components and genotype × year interactions for different traits determining the consensus between morphological and molecular data under two environmental conditions. Forty pea accessions were evaluated during 2005, a year with no temperature or rainfall stress, and 2006, a stress year. Morphologic, productive, and sequence‐related amplified polymorphism (SRAP) data were collected. Phenotypic and genotypic variances were determined and heritability estimated. One hundred and sixty‐two polymorphic SRAP bands were scored. Regressions between morphological and SRAP data were conducted. In a stressful year the correlation between SRAP and morphological data was higher than in a non‐stressed season (r = 0.72 versus r = 0.55). The results suggest that exposure to combinations of environmental stresses may increase expression of genetic variability for productive traits.