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Detailed anatomical studies of flowers and fruits may render traits of phylogenetic importance, but are still rare in the Boraginales. An Old World clade of Cordia comprises many dioecious species, but the floral anatomy is largely unexplored and, hence, the structural basis for sex separation. Fresh material of buds, functionally unisexual flowers and fruits were studied using a stack shot camera. Fixed such material of Cordia crenata, C. cf. grandicalyx and C. sinensis was sectioned using a microtome and stained with safranin red and astra blue, and the gynoecial surface was studied using SEM. The stamens of the female flowers are largely intact, but do not produce pollen, whereas the gynoecium of the male flowers is highly reduced though develops ovules lacking an embryo sac. The morphologically rather unreduced stamens of the female flower may have undergone a shift of function from producing pollen towards attracting pollinators by optical signals. The outer parenchyma of the gynoecium is strongly stained and after fertilisation, one through three ovules are maturing towards seeds. The presence of more than a single seed enclosed in the undivided endocarp is rare in Cordiaceae. [ABSTRACT FROM AUTHOR]

Coffee plants contain well-known xanthines as caffeine. Three Coffea species grown in a controlled greenhouse environment were the focus of this research. Coffea arabica and C. canephora are two first principal commercial species and commonly known as arabica and robusta, respectively. Originating in Central Africa, C. anthonyi is a novel species with small leaves. The xanthine metabolites in flower, fruit and leaf extracts were compared using both targeted and untargeted metabolomics approaches. We evaluated how the xanthine derivatives and FQA isomers relate to the expression of biosynthetic genes encoding N - and O -methyltransferases. Theobromine built up in leaves of C. anthonyi because caffeine biosynthesis was hindered in the absence of synthase gene expression. Despite this, green fruits expressed these genes and they produced caffeine. Given that C. anthonyi evolved successfully over time, these findings put into question the defensive role of caffeine in leaves. An overview of the histolocalisation of xanthines in the different flower parts of Coffea arabica was also provided. The gynoecium contained more theobromine than the flower buds or petals. This could be attributed to increased caffeine biosynthesis before fructification. The presence of theophylline and the absence of theobromine in the petals indicate that caffeine is catabolized more in the petals than in the gynoecium. [Display omitted] • Xanthine biosynthesis of the recently identified Coffea anthonyi species is compared to that of C. arabica and C. canephora. • Caffeine biosynthesis is disrupted in leaves but active in fruits of C. anthonyi. • Data from C. arabica indicate that caffeine synthesis begins in the gynoecium. • C. anthonyi does not express the DXMT genes in leaves, although these are conserved across the majority of Coffea species. [ABSTRACT FROM AUTHOR]