Synthetic taxonomy of Rosa races using ACT-STATIS.

Fifteen Rosa cultivated races were described by means of phenotypic frequencies (11 tables). Two groups of correlated contingency tables were identified by ACT-STATIS (Analyse Conjointe de Tableaux-Structuration de Tableaux à Trois Indices de la Statistique) interstructure analysis. Three data sets appeared to be independent from the others. Typologies of races were obtained after ACT-STATIS compromise analyses for the two groups of correlated tables, and after Principal Component Analyses for the independent data sets. Each typology was original and variously influenced by genealogical structure, mutation or artificial selection pressures. A weighted synthesis was attempted in order to build a taxonomy of races taking into account these diversity factors. The good agreement between the resulting classification and the assumptions about the history of Rosa domestication advocated for a wider utilization of ACT-STATIS and RV coefficient when the relationships between individuals or populations have to be studied on the basis of their similarities.

The domestication syndrome within Hybrid Perpetuals roses: the effect of unconscious selection on flavonoids.

Cultivated GallicanaexChinenses hybrids of roses, namely Hybrid Perpetuals, were compared with their parents as to morphology, petal colour, flavonol and anthocyanin metabolism. Morphology exhibited clear patterns of hybridity. An objective measure of petal lightness (L) indicated that Hybrid Perpetuals were submitted to a selection pressure favouring dark-flowered cultivars. When compared to the parental flavonoid metabolisms, Hybrid Perpetuals exhibited increased synthesis of anthocyanin and quercetin. High amounts of anthocyanin in Hybrid Perpetuals resulted from the selection of deeper-coloured flowers. High amounts of quercetin were correlated with enhanced anthocyanin synthesis, so that this originality of the flavonol metabolism was interpreted on biogenetic ground as a repercussion of this same selection pressure. Finally, the patterns of variation of flavonol glycosides within the Hybrid Perpetuals reflected the indirect selection pressure for the quercetin end-products, and with the ancestral hybridizations for the kaempferol derivatives.

Bacterial carotenoids, XLVI. C50-Carotenoids, 14. C50-Carotenoids from Arthrobacter glacialis.

From the psychrophilic bacterium Arthrobacter glacialis have been isolated three C50-carotenoids with molecular formulae C50H72O2: the bicyclic decaprenoxanthin (1a, 7% of total carotenoids), the aliphatic bisanhydrobacterioruberin (2a, 10%) and the monocyclic A.g. 470 (3a, 83%). Decaprenoxanthin (1) and bisanhydrobacterioruberin (2) were in all respects, including chiroptical properties, identical with known carotenoids. The constitution of the previously undescribed A.g. 470 (3a) followed from its spectral properties (electronic, 1H NMR including Eu-shift experiments and mass spectra) and derivatization to 3b and 3c. 3a suffered remarkable elimination to the tridecaene 4a (C47H64O) upon DMSO/KOMe/MeOH treatment. Judged by CD data A.g. 470 (3a) also in stereochemical respect 3a appears to be half decaprenoxanthin (1a)+half bisanhydrobacterioruberin (2a). The intensity ratios of the M-92/M-106 ions on electron impact of 3a,b,c and 4a,b are consistent with the general theory.