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Premise of the Study: Loranthaceae, Santalaceae, and Viscaceae are the most diversified hemiparasitic families of Santalales in the Andes. Their partial inflorescences (PIs) vary from solitary flowers, or dichasia in most Santalales, to congested floral groups along articles in most Viscaceae. The atypical articled inflorescences in Phoradendreae (Viscaceae), a phylogenetic novelty restricted to this tribe, have been variously described as racemes, spikes, fascicles, or as intercalary inflorescences, but no developmental studies have been performed to compare them with the construction of PIs across Santalales., Methods: We used standard light microscopy and scanning electron microscopy to record the inflorescence development in members of Phoradendreae (Viscaceae) in comparison to those in species of Aetanthus, Gaiadendron, Oryctanthus, Passovia, and Peristethium (Loranthaceae) and Antidaphne (Santalaceae)., Key Results: Morphological and developmental comparisons as well as optimization onto a phylogenetic framework indicate that individual inflorescences in Santalales are indeterminate and are formed by axillary cymose PIs. The latter correspond to dichasia, either simple, compound, or variously reduced by abortion of lateral flowers, abortion of the terminal flower, or loss of bracteoles., Conclusions: Dichasia are plesiomorphic in Santalales. These results favor the interpretation that inflorescences in Phoradendreae are formed by the fusion of serial dichasia (=floral rows) with the main inflorescence axis via syndesmy. We compared this interpretation with the competing one based on the co-occurrence of collateral and serial floral buds., (© 2017 Botanical Society of America.)

Objective: To study species diversity and the host of Thesium chinense community., Method: The investigation on phytocoenology was carried out on the T. chinense community in 7 areas of Anhui Province and Jiangsu Province. The correlation between species diversity of community and T. chinense abundance was analyzed regarding to the abundance of species, the abundant index of species, species diversity index and community even index., Result and Conclusion: The results showed that T. chinense liked light, warm climate, liked acidic to neuter soil. The majority of T. chinense distributed in the humid wasteland and herbaceous community. There was a positive correlation between the abundance of T. chinense and the unity numbers of community, and a negative correlation between the abundance of T. chinense and the abundance, coverage, diversity index, Pielou even index of community. T. chinense host species was various. This investigation found 28 host species belong to 11 Families, among them 5 Families and 18 species were found for the first time.

The "talares" in eastern Buenos Aires province, Argentina, are coastal xerophitic forests structured by few arboreal species surrounded by a lower and moister soil matrix. We studied the reproductive parameters of the most representative arboreal species (Celtis tala, Scutia buxifolia, Jodina rhombifolia, and Schinus longifolia). Pollen dispersion was studied through floral visitor traps (biotic dispersion) and using gravimetric pollen collectors (abiotic dispersion). The reproductive success (fruit formation rate) of the focal species was studied by enclosing flowers with different mesh bags. The reproductive system varied among the different species. C. tala was anemophilous and selfcompatible. S. buxifolia was entomophilous and floral visitors dependant. J. rhombifolia was entomophylous, although spontaneous autogamy could favor reproduction in the absence of pollinators. Lastly, S. longifolia could be an ambophilous species (pollinated by insects and by the wind). This dual system may be the result of system flexibility mechanism or an evolutionary transition.

We have tried to elucidate the origin of phytochemical variation in trees by studying concomitantly the chemical and microsatellite variations in Santalum austrocaledonicum. Eight natural populations were sampled in the New-Caledonian archipelago, a total of 157 individuals being analyzed. The main components, as revealed by gas chromatography (GC), were alpha- and beta-santalol (as in other sandalwood species), although the level of (Z)-lanceol was particularly high. Most of the chemical variation was observed within populations (83.7%). With microsatellites, the variation between populations was more pronounced (32% of the total variation). Although the chemical variation between populations was small, we investigated the effects of genetic drift and migration by comparing the chemical- and molecular-differentiation patterns. The poor congruence between neighbor-joining trees, confirmed by the non-significant Mantel test between the molecular and chemical distance matrices (R=0.26, P=0.12), showed that genetic drift and migration are not the main evolutionary forces acting on chemical differentiation between populations. We could not find any effect of soil and rainfall conditions neither. Although the impact of drift and migration cannot be discounted in rationalizing between-population differentiation, the low variation among populations could result from a stabilizing selection caused by the same phytopathogen charge across the natural range.

From the twigs of Scleropyrum wallichianum, a new unsaturated carboxylic acid, scleropyric acid (1), two new esters, beta-sitosteryl-3-O-scleropyrate (2) and stigmasteryl-3-O-scleropyrate (3), and two well-known sterols, beta-sitosterol (4) and stigmasterol (5), were isolated and characterized using spectroscopic methods. Compound 1 exhibited antimycobacterial activity with an MIC value of 25 microg/ml and showed antiplasmodial activity with an IC50 value of 7.2 microg/ml. Compounds 2 and 3 were inactive in both assays.