Hempseed could be a new source of proteins and oil for both humans and animals. In this study, the proximate composition of a collection of hempseed cultivars and accessions of different geographical origins grown under the same conditions was analyzed. Fatty acids, tocopherols and antinutritional components, as well as concentrations of crude protein and oil were quantified. Hempseed oil concentrations varied between 285 and 360 g kg-1 dry seed (DS), while crude protein ranged between 316 and 356 g kg-1 dry matter (DM). The hempseed oil was mainly composed of unsaturated fatty acids and, as expected, the dominant fatty acids were linoleic and α-linolenic acid. A high variability among the cultivars and accessions was also detected for polyphenolic content which ranged from 5.88 to 10.63 g kg-1 DM, cv. Felina was the richest, whereas cv. Finola had the lowest polyphenolic content. Regarding antinutritional compounds in seed, a high variability was detected among all genotypes analyzed and phytic acid was particularly abundant (ranging between 43 and 75 g kg-1 DM). In conclusion, our results reveal noticeable differences among hempseed genotypes for antinutritional components, oil and protein content. Collectively, this study suggests that the hempseed is an interesting product in terms of protein, oil and antioxidant molecules but a reduction of phytic acid would be desirable for both humans and monogastric animals. The high variability detected among the different genotypes indicates that an improvement of hempseed might be possible by conventional and/or molecular breeding.

In higher eukaryotes, the DNA composition of centromeres displays a high degree of variation, even between chromosomes of a single species. However, the long-range organization of centromeric DNA apparently follows similar structural rules. In our study, a comparative analysis of the DNA at centromeric regions ofBetaspecies, including cultivated and wild beets, was performed using a set of repetitive DNA sequences. Our results show that these regions inBetagenomes have a complex structure and consist of variable repetitive sequences, including satellite DNA, Ty3-gypsy-like retrotransposons, and microsatellites. Based on their molecular characterization and chromosomal distribution determined by fluorescent in situ hybridization (FISH), centromeric repeated DNA sequences were grouped into three classes. By high-resolution multicolor-FISH on pachytene chromosomes and extended DNA fibers we analyzed the long-range organization of centromeric DNA sequences, leading to a structural model of a centromeric region of the wild beet speciesBeta procumbens. The chromosomal mutants PRO1 and PAT2 contain a single wild beet minichromosome with centromere activity and provide, together with cloned centromeric DNA sequences, an experimental system toward the molecular isolation of individual plant centromeres. In particular, FISH to extended DNA fibers of the PRO1 minichromosome and pulsed-field gel electrophoresis of large restriction fragments enabled estimations of the array size, interspersion patterns, and higher order organization of these centromere-associated satellite families. Regarding the overall structure,Betacentromeric regions show similarities to their counterparts in the few animal and plant species in which centromeres have been analyzed in detail.[The sequence data described in this paper have been submitted to the EMBL data library under accession nos.AJ278751,AJ278752, andAJ243337.