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On the Chilean mistletoe “Quintral”, there has been limited literature, despite the fact the numerous uses and ubiquity amongst the Mapuche natives in Chile and Argentina. Therefore, our research group has carried out an exhaustive extraction with solvents of increasing polarity to Quintral flowers and leaves hosted in three different host species. With the extracts of different polarities, a phytochemical screening was performed, finding the presence of glycosides, sterols, terpenoids and quinones which are documented to convey different applications in cardiovascular or gastric afflictions. Likewise, the content of total phenols, total flavonoids and the reducing power of all the extracts were determined, displaying significant differences for the three varieties. Leaf and flower of the “Huayun Quintral” in methanol extracts gave the highest values of reducing power, while leaf and flower methanol extracts of “Maqui Quintral” showed the highest values for total phenols. Also observed are the lower polarity extracts from Quintral, contributing to the reducing capability by means of non-phenolic compounds.

The high Andean forests of the genus Polylepis (Rosaceae) are threatened by extinction due to anthropogenic effects such as timber extraction, burning, and overgrazing. Some species are also affected by Tristerix chodatianus (Loranthaceae), a hemiparasitic plant which induces progressive host damage. To understand this hemiparasitic process, we evaluated the impact of T. chodatianus on growth and the wood anatomy of Polylepis flavipila using growth rings and digital image processing. We found that P. flavipila has a xeromorphic wood anatomy and that the ecological indices of mesomorphism and vulnerability decrease at higher elevations to avoid embolisms and vessel cavitation. Tristerix chodatianus causes anatomical changes in the host wood, mainly in the last 13 years measured. Alterations include a reduction in the vessel density, and an increase in the vessel diameter and Vulnerability Index, all of which are more evident in downstream sections of parasitized branches. These changes in the xylem tissues increase the vulnerability of the parasitized branches to embolisms and cavitation, thus leading to progressive death of the tree crown. Our study confirms that the analysis of the wood anatomy of parasitized branches can be used to determine the years of colonization of a tree branch by a hemiparasite and that it can be a useful tool to monitor the phytosanitary state of parasitized Polylepis trees.

Premise of research. The New World Loranthaceae correspond to a polyphyletic assembly of hemiparasites that exhibit a high floral diversity in terms of size, merism, groundplan, symmetry, and polli...

On the Chilean mistletoe “Quintral”, there has been limited literature, despite the fact the numerous uses and ubiquity amongst the Mapuche natives in Chile and Argentina. Therefore, our research group has carried out an exhaustive extraction with solvents of increasing polarity to Quintral flowers and leaves hosted in three different host species. With the extracts of different polarities, a phytochemical screening was performed, finding the presence of glycosides, sterols, terpenoids and quinones which are documented to convey different applications in cardiovascular or gastric afflictions. Likewise, the content of total phenols, total flavonoids and the reducing power of all the extracts were determined, displaying significant differences for the three varieties. Leaf and flower of the “Huayún Quintral” in methanol extracts gave the highest values of reducing power, while leaf and flower methanol extracts of “Maqui Quintral” showed the highest values for total phenols. Also observed are the lower polarity extracts from Quintral, contributing to the reducing capability by means of non-phenolic compounds.

There are 11 species of mistletoes in the genus Tristerix (Loranthaceae) endemic to the Andes in South America (1,2). Tristerix verticillatus (Ruiz & Pav.) Barlow & Wiens is distributed on the east side of the Andes from Bolivia to Argentina at high elevations (>1,500 m). On the west side of the Andes, it is only found in Chile where it occurs at low to high elevations (50 to 3,000 m). Along its range, the mistletoe parasitizes more than 25 species, mainly Anarcadiaceae and Rhamnaceae. In February of 2007, it was observed to be parasitizing Schinus fasciculatus (Griseb.) I.M. Johnst. (Anacardiaceae) at two locations in the Sierra de San Luis, Argentina. One location was 6 km south of Las Chacras on Route 31 (32°35′56″S, 65°47′6″W, elevation 1,185 m) and the other was 12 km north of El Trapiche on Route 9 (33°1′21″S, 66°4′11″W, elevation 1,260 m). At these localities, the mistletoe was in full flower and parasitized only one host species, S. fasciculatus. No mortality associated with infection by this mistletoe was observed at either location. Specimens of the mistletoe were collected from both locations and deposited at the Centro Regional Universitario Bariloche Herbarium (BCRU), Río Negro, Argentina. To our knowledge, this is the first report of a Tristerix sp. outside the Andes and extends the eastern distribution of the genus by ≈270 km and also of S. fasciculatus serving as a host for T. verticillatus since previous collections were from other species of Schinus. References: (1) G. C. Amico et al. Am. J. Bot. 94:558, 2007. (2) J. Kuijt, Syst. Bot. Monogr. 19, 1988.

A new, large-flowered species of Tristerix, T. rhodanthus, is described and illustrated from Bolivia

Loranthaceae (73 genera and ca. 900 species) comprise mostly aerial hemiparasitic plants. Three monotypic genera considered relicts are root parasites. The family is diverse in tropical areas, but representatives are also found in temperate habitats. Previous classifications were based on floral and inflorescence morphology, karyological information, and biogeography. The family has been divided into three tribes: Nuytsiae, Elytrantheae (subtribes Elytranthinae and Gaiadendrinae), and Lorantheae (subtribes Loranthinae and Psittacanthinae). Nuytsiae and Elytrantheae are characterized by a base chromosome number of x = 12, whereas subtribes Loranthinae (x = 9) and Psittacanthinae (x = 8) numbers are derived via aneuploid reduction. To elucidate the phylogeny of the family, we analyzed sequences from five genes (nuclear small and large subunit rDNA and the chloroplast genes rbcL, matK, and trnL-F) representing most genera using parsimony, likelihood, and Bayesian inference. The three root parasites, Nuytsia, Atkinsonia, and Gaiadendron, are supported as successive sister taxa to the remaining genera, resulting in a monophyletic group of aerial parasites. Three major clades are resolved each corresponding to a subtribe. However, two South American genera (Tristerix and Notanthera) and the New Zealand genus Tupeia, which were previously classified in subtribe Elytranthinae, are weakly supported as part of a clade representing the South American subtribe Psittacanthinae.

Aphids belonging to the genus Aphis collected on species of Discaria, Condalia, Colletia, and Trevoa (Rhamnaceae), and on Tristerix sp. (Loranthaceae) parasitic on Colletia spinosissima, in Argentina and Chile were studied. Apterous parthenogenetic females (fundatrigeniae and fundatrices), viviparous alatae females, oviparous females, and males of Aphis conflicta, n. sp., are described. A key to Aphidini species that could be found on Rhamnaceae in South America is given.

Floral diversification in Loranthaceae reaches its highest peak in the Andes. The flowers of the exclusively Andean genus Tristerix exhibit tubular and vividly coloured flowers pollinated by hummingbirds. We studied inflorescence and flower morphoanatomy of the two Colombian species, T. longebracteatus and the highly endangered T. secundus . Both species have terminal racemes with up to 26 ebracteolate flowers, of which the proximal one opens and sets fruits first. The slightly irregular calyx initiation is followed by the simultaneous initiation of petals and the successive initiation of stamens. Anthesis is fenestrate, explosive, and triggered by the tension of the style against the abaxial petals, a mode so far not reported in Loranthaceae . Anthetic petals spread symmetrically in T. longebracteatus and asymmetrically in T. secundus . Nectar is produced by a supraovarial disk and by the petal mesophyll. Floral lifespan lasts up to 20 days. The hummingbirds Eriocnemis vestita and Pterophanes cyanopterus are the likely pollinators of T. secundus . Morphological traits are inconclusive to support one of the two competing sister group relationships that involve Tristerix , as the lack of cataphylls in renewal shoots links Ligaria and Tristerix , whereas the terminal inflorescences support its relationship with Desmaria and Tupeia .

The alteration and transformation of the areas surrounding native forests due to anthropogenic disturbance can result in differences near this newly created boundary, termed 'edge effects'. Our study describes the consequences of edge creation over two successive stages in the life cycle of a hemi-parasitic mistletoe (Tristerix corymbosus), which determine its reproductive success, in temperate austral forests. We assessed how flower production and pollinator visits change with distance to the nearest forest edge and how these changes affect fruit set, fruit and seed size, and fruit removal by seed dispersers. Edge effects were dominated by fruit removal, which increased with the distance to the edge, height in the canopy and fruit availability. As a result, plant reproduction (in terms of seeds produced and fruits removed, which putatively leads to higher seed dispersal) decreased strongly near to forest edges. In contrast, visitation rates of the main pollinator (the hummingbird) were unaffected by edges, and their strong effects on fruit set (including the alleviation of quality pollen limitation arising in the forest interior) might be mitigating the decrease in bumblebee visitation near to forest edges. Synthesis. Our study shows clearly how secondary and tertiary responses to forest edges acted in opposite directions (increasing or decreasing plant reproductive performance), highlighting the need to study several successive processes that impact upon plant fitness under disturbance. Preserving relatively large patches of old-growth forest with low perimeter/area ratios would be key to the habitat requirements of the main disperser and pollinator and thus for mistletoe reproductive performance. © 2013 The Authors. Journal of Ecology © 2013 British Ecological Society., Funding by the BBVA Foundation (project DOSEL) and the Basque Country Government (pre-doctoral fellowship for A.M.) made this study possible. A.R.L. received funding from the JAEDOC program of the Spanish Research Council (CSIC)

Nectar robbing may have an indirect negative effect on plant reproduction by discouraging legitimate pollinator species from visiting robbed flowers. In this study, we set up a 2 × 2 factorial design with nectar-robbing ants and hummingbird pollination to test for non-additive effects on fruit set, seed mass, and seed germination of the leafless mistletoe Tristerix aphyllus (Loranthaceae). Even though ants caused conspicuous damage at the base of the floral tubes, nectar availability was reduced by only 8 % in the presence of ants. The green-backed firecrown Sephanoides sephaniodes was insensitive to the presence of ants. Rather, the bird responded to flower number and the presence or the absence of damage, but not to the extent of damage within inflorescences. As hummingbirds were largely insensitive to variation in nectar robbing, the interaction ant × hummingbird had no effect on plant-reproductive success. Thus, the factorial experiment did not provide evidence for indirect negative effects of nectar robbing on plant reproduction. These results suggest that indirect effects of nectar robbers on pollinator behaviour may occur under a more restricted set of conditions than those previously considered. We suggest that the low amount of nectar removed by nectar-robbing ants was insufficient for hummingbirds to avoid robbed flowers, which restricted the potential for non-additive effects.

Phylogenies can provide valuable information on biotic and abiotic factors associated with speciation. We examined species relationships in Tristerix (Loranthaceae), a genus of 11 species with an Andean distribution from Colombia to Chile. A previous classification divided Tristerix into subgenera Tristerix (two species) and Metastachys (nine species). We tested this classification by generating a molecular phylogeny of the genus using nuclear ribosomal DNA ITS and chloroplast atpB-rbcL intergenic spacer and trnL-F regions. All partitions generally gave congruent trees, thus a combined analysis was conducted. Tristerix was composed of a northern clade (six species) and a southern clade (four species). Tristerix verticillatus and T. penduliflorus (Metastachys) were strongly supported as members of the (southern) subgenus Tristerix clade. Speciation appears to be correlated with the emergence of matorral and cloud forest biomes and is driven by interactions with pollinators and seed dispersers. Tristerix aphyllus is sister to T. corymbosus of the matorral, not to neighboring temperate forest populations, thus rendering the latter species paraphyletic. This ecological speciation event may have occurred in sympatry. Tristerix provides excellent examples of how, during the orography of the Andes, many dynamic and interacting ecological factors have influenced their speciation.

Lonicera corymbosa Linnaeus, Species Plantarum 1: 175. 1753. "Habitat in Peru." RCN: 1383. Lectotype (Kuijt in Syst. Bot. Monogr. 19: 20. 1988): [icon] " Periclymenum foliis acutis, floribus profunde dissectis, vulgo y tiu " in Feuillée, J. Obs. 2: 760, t. 45. 1714. Current name: Tristerix corymbosus (L.) Kuijt (Caprifoliaceae)., Published as part of Jarvis, Charlie, 2007, Chapter 7: Linnaean Plant Names and their Types (part L), pp. 610-650 in Order out of Chaos. Linnaean Plant Types and their Types, London :Linnaean Society of London in association with the Natural History Museum on page 640, DOI: 10.5281/zenodo.291971

Interactions between a Chilean mistletoe, quintral (Tristerix tetrandrus, Loranthaceae) and its potential host plants were studied at a site with mediterranean type climate. The results show that the distribution of T. tetrandrus is related to the behavior of avian dispersers, which feed on its fruit, and evacuate the seeds at random in the field, but the distribution is also influenced bymicroenvironmental conditions, survival of seedlings is hampered at drier locations. The infection capacity of the seeds is increased after birds have eliminated the fruit coat.Survival of T. tetrandrus seeds differed depending on the species to which they were attached experimentally. Seeds germinated, and plants developed on Colliguaya odorifera and Kageneckia oblonga, previously reported as susceptible to infection. Survival was significantly higher on C. odorifera, although in the field it is infected less frequently than K. oblonga. In species on which no T. tetrandrus has been previously reported, resistance to infection might be ascribed to different mechanisms: in Quillaja saponaria, differentiation of cork layers apparently prevents penetration by haustoria; in Lithraea caustica haustoria enter the cortex and phloem, but no further development ensues. K. oblonga seldom bears more than one T. tetrandrus plant. Experimental inoculations showed that significantly more seeds developed into plants on K. oblonga individuals not previously infected with quintral, suggesting that they become resistant to infection.

The evolution of flowering time can be influenced directly by pollinators and indirectly by seed dispersers. In temperate latitudes, interactions with climate, especially temperature, may affect both plants and their animal mutualists. Winter-flowering plants allow assessment of biotic influences on the evolution of flowering time because temperature is unlikely to select directly for this uncommon reproductive behavior. In northwestern Patagonia, the hemiparasitic mistletoe Tristerix corymbosusflowers from early fall, through the cool winter, to late spring. This species is pollinated by the hummingbird Sephanoides galeritus, and its seeds are dispersed by the marsupial Dromiciops australis. In two pop- ulations during two years, I analyzed seasonal variation in pollination, fruit production, and fruit removal. Hummingbird visitation was lowest in winter and late spring, and flowers opening during those periods showed reduced pollination and fruit set, partly due to pol- linator limitation, compared to flowers that opened during fall or early spring. Fruits that ripened during summer (January-March) had a higher chance of being removed than fruits ripening during either spring or fall, due to their overlap with the period of maximum disperser activity. Timing of flower opening was strongly associated with fruit maturation time and with fruit removal rates. Thus, even though flowers that opened during winter exhibited only moderate fruit production, their fruits benefited from high fruit removal and seed dispersal in mid to late summer. These results suggest that the activity period of this plant's disperser, in combination with a lack of strong pollination constraints, probably governed the evolution of flowering phenology in this mistletoe. However, the proximate influence of temperature on flower and fruit development may prevent a fine-tuned match between flowering phenology and the period of maximum mutualist activity.