En el presente trabajo damos a conocer la diversidad de fl oración y fructifi cación observada du- rante un año de estudio fenológico en la Reserva de Paucarillo (noroeste de la Amazonía Peruana 3°41’ S, 72°24’ W). Registramos un total de 270 especies en 59 familias, de las cuales el 57% son representadas solamente por 1 individuo. Las Arecaceae y Rubiaceae fueron las familias dominantes en este sitio.

Abstract The goal of this study was to determine whether seed longevity is an indicator of invasive potential. We studied annual (Polygonum) and woody perennial (Celastrus, Parthenocissus) non-native species and their native congeners in a three-year buried seed experiment. The woody perennial species formed a transient seed bank lasting only one year. In year one, both perennial non-native species had significantly greater germination than their native congeners. Both Polygonum species formed a persistent seed bank, but the invasive P. perfoliatum had greater longevity than the native P. sagittatum. The study demonstrated that seed bank strategies of invasive species are qualitatively similar to their less abundant native congeners, but there were significant quantitative differences.

AbstractThis chapter considers the process of seed acquisition by animals (or animal acquisition by seeds), the nature of seed treatment by the animals, animal mobility and seed deposition patterns, and finally the diversity of animals that disperse seeds.

Thrushes consume a variety of fruit that differ greatly in nutrient composition, especially lipid content. Thrushes may be efficient at extracting energy from fruit diets by changing how they digest meals differing in lipid content. We tested for this capability in American robins (Turdus migratorius) by acclimating them to diets differing in lipid content and measuring passage rate and absorption efficiency of ingested lipids with radiolabeled markers. Birds acclimated to high-lipid (26% and 40% dwt) diets ingested less dry matter and retained ingested lipids in their gastrointestinal tract three times longer than when acclimated to a low-lipid (9%) diet. Absorption efficiency did not differ among diets (˜74%), suggesting robins minimize feeding time rather than maximize rate of energy gain when processing meals. Thus, robins slowed intake and passage rate of dietary lipids with increasing dietary lipid concentration while maintaining a steady lipid absorption efficiency. J. Exp. Zool. 283:408–417, 1999. © 1999 Wiley-Liss, Inc.

TaxolTM (Paclitaxel), epirubicin and cyclophosphamide (TEC) in the treatment of metastatic breast cancer (MBC): results of a phase I study J-M Nabholtz, K Khoo, JR Mackey, M Smylie, T Al-Tweigeri, D Dudgeon, 0 Keller, 0 Foerster, C Olweny, T Shore, E Sansregret, E Stiles, H Dulude, G Gallant, B Brown Cross Cancer Institute, Edmonton, Alberta: Manitoba Cancer Foundation; Bristol-Myers Squibb, Montreal, Canada

Seed predation may be an important factor influencing the structure of successional plant communities. We used a cafeteria-style experiment, placed in an old field and an early successional forest, to determine predator preferences for seeds of nine species of woody plants. Intensity of seed predation was equivalent in both sites. Seed predators preferred Acer saccharum, Ilex verticillata, and Viburnum dentatum, but this was not related to seed mass. Predation intensity was more variable in the old field than in the forest, possibly related to the higher ground-layer heterogeneity of the old field site. We conclude that predator choice will allow some species to escape seed predation, potentially altering future plant community composition.

We measured pollinator visits of Impatiens capensis flowers found in different-sized patches beneath canopy gaps and beneath closed canopy in a mature, old-growth deciduous forest in New Jersey. Honeybees, bumblebees and halictid bees made up the majority of visitors. Visitation rates per flower increased slightly, but not significantly, in relation to flower patch size (number of open flowers) and floral density. By contrast, pollinator visitation rates, floral density and seed production per pod were all significantly higher in patches located beneath forest canopy gaps compared to patches located beneath closed canopy.

Dispersal of seeds by adhesion to animals, known as epizoochory, is often referred to as a significant mode of dispersal. Few studies have quantitatively examined this method of dispersal; those that do often concentrate on mammalian rather than avian dispersers. To measure the extent of this form of seed dispersal, we studied the external seed loads on the feet and feathers of four waterfowl species found in a salt marsh on the New Jersey shore. More than 75% of the birds were found to be carrying seeds, mostly on their feathers. The seeds of twelve plant species, predominantly from salt marsh plants and particularly salt grass (Distichlis spicata) and cordgrass (Spartina alterniflora), were identified in the samples. All but one species has seeds with potentially adhesive structures. Results indicate that for many salt marsh plant species, seed dispersal by adhesion to waterfowl may be a significant method of seed transport.

Use patterns of lipid-rich, fleshy fruits were examined for frugivorous birds. Approximately 20% of fleshy-fruited species within plant communities bear fruit with >10% dry weight lipids. These fruits are fed upon by the most heavily frugivorous bird species in those communities studied and are the focus of highly specialized relationships among birds and fruits. In aviary tests some temperate frugivores show preference for higher lipid native fruits and prefer higher-lipid artificial fruits with as little as 3% wet weight difference in lipid content. The importance of lipids in fruit preference by birds, and the possible effects of differing digestive physiologies in birds are discussed.

We tested several predictions concerning fungal rot and antifungal defense of vertebrate—dispersed fruit. (1) Fungal fruit to should be generally deterrent to frugivores. But because fungi may vary in their negative effects, antifungal defenses should be allocated in relationship to net effects of particular species on dispersal. (2) Defenses of fruits under selection for high palatability should be directed primarily toward microbes ("microbespecific" defenses). Lower quality fruits, for which high palatability is not crucial to dispersal, may be defended by more general defenses. (3) Preferred fruits should be defended to a lower degree than less preferred fruits, as a result of consistently high dispersal rates (Removal Rate model). We tested our hypotheses using real fruits and artificial—pulp media of six temperate ericaceous plants in feeding trials with captive birds and in fungal growth trials. Plants had been assigned to two temperature fruiting classes (Summer Small—seeded, SS, Fall—Low—quality, FL), and differed in ripening phenology, persistence times, and fungal resistance in the field. We compared feeding rates on fruits rotted by members of a suite of fruit rot fungi. We also determined feeding rates on artifical—pulp media that either contained ripe fruit extracts or did not, and we determined fungal growth rates on identical media. We found that: (1) fungal species depressed feeding rates in general accordance with their reported vertebrate toxicity. Relative to nontoxic fungi, toxic fungi were inhibited more strongly by secondary fruit pulp extracts. (2) Artificial—pulp media of SS fruits were preferred in feeding trials, due both to basic nutritional composition and nondeterrent (microbe—specific) secondary defense. (3) In accordance with the Removal—Rate model, artificial—pulp media of the preferred SS fruits showed significant antifungal activity, but at a much lower level than that of FL fruits. Our results suggest that a primary function of secondary chemicals in ripe fruits may be to defend against destructive fungi that compete with seed dispersers for the pulp. Our results generally support the hypothesis that selective pressures may result in ripe fruit defenses that are directed primarily against organisms having strong negative effects upon dispersal. As such, factors influencing risk of pulp consumption by nondispersers may be useful predictors of fruit defense patterns.

Previous articleNext article No AccessNotes and CommentsFungi as Biotic Defense Agents of Fleshy Fruits: Alternative Hypotheses, Predictions, and EvidenceMartin L. Cipollini, and Edmund W. StilesMartin L. Cipollini Search for more articles by this author , and Edmund W. Stiles Search for more articles by this author PDFPDF PLUS Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinkedInRedditEmail SectionsMoreDetailsFiguresReferencesCited by The American Naturalist Volume 141, Number 4Apr., 1993 Published for The American Society of Naturalists Article DOIhttps://doi.org/10.1086/285498 Views: 5Total views on this site Citations: 14Citations are reported from Crossref Copyright 1993 The University of ChicagoPDF download Crossref reports the following articles citing this article:Christa P. H. Mulder, Katie V. Spellman, Jasmine Shaw BERRIES IN WINTER: A NATURAL HISTORY OF FRUIT RETENTION IN FOUR SPECIES ACROSS ALASKA, Madroño 68, no.44 (Oct 2021).https://doi.org/10.3120/0024-9637-68.4.487Renan F. Moura, Eva Colberg, Estevão Alves-Silva, Isamara Mendes-Silva, Roberth Fagundes, Vanessa Stefani, Kleber Del-Claro Biotic Defenses Against Herbivory, (May 2021): 93–118.https://doi.org/10.1007/978-3-030-66877-8_5Lauren D. Maynard, Heather L. Slinn, Andrea E. Glassmire, Bernal Matarrita‐Carranza, Craig D. Dodson, Trang T. Nguyen, Megan J. Burroughs, Lee A. Dyer, Christopher S. Jeffrey, Susan R. Whitehead Secondary metabolites in a neotropical shrub: spatiotemporal allocation and role in fruit defense and dispersal, Ecology 101, no.1212 (Oct 2020).https://doi.org/10.1002/ecy.3192Josep E. Peris, Ana Rodríguez, Leandro Peña, José María Fedriani Fungal infestation boosts fruit aroma and fruit removal by mammals and birds, Scientific Reports 7, no.11 (Jul 2017).https://doi.org/10.1038/s41598-017-05643-zNoelle G. Beckman, Joanna E. Lambert The Distribution of Fruit and Seed Toxicity during Development for Eleven Neotropical Trees and Vines in Central Panama, PLoS ONE 8, no.77 (Jul 2013): e66764.https://doi.org/10.1371/journal.pone.0066764Noelle G. Beckman, Helene C. Muller-Landau Linking fruit traits to variation in predispersal vertebrate seed predation, insect seed predation, and pathogen attack, Ecology 92, no.1111 (Nov 2011): 2131–2140.https://doi.org/10.1890/10-2378.1Francisco Sánchez, Carmi Korine, Burt P. Kotler, Berry Pinshow Ethanol concentration in food and body condition affect foraging behavior in Egyptian fruit bats (Rousettus aegyptiacus), Naturwissenschaften 95, no.66 (Mar 2008): 561–567.https://doi.org/10.1007/s00114-008-0359-yR Dudley Evolutionary and Historical Aspects of Ethanol Ingestion I thank Paul Gruenewald, Carmi Korine, Berry Pinshow, and Dustin Stephens for commenting on the manuscript., (Jan 2005): 3–13.https://doi.org/10.1016/B978-012564370-2/50003-9Joshua J. Tewksbury Fruits, frugivores and the evolutionary arms race, New Phytologist 156, no.22 (Oct 2002): 137–139.https://doi.org/10.1046/j.1469-8137.2002.00522.x References, (Jan 2001): 131–160.https://doi.org/10.1016/B978-012675555-8/50008-7 Robert Dudley Evolutionary Origins of Human Alcoholism in Primate Frugivory, The Quarterly Review of Biology 75, no.11 (Oct 2015): 3–15.https://doi.org/10.1086/393255Keith Clay, Wim van der Putten Pathogens and Plant Life Histories, (Jan 1999): 275–301.https://doi.org/10.1007/978-94-010-9460-3_9 Martin L. Cipollini and Douglas J. Levey Secondary Metabolites of Fleshy Vertebrate‐Dispersed Fruits: Adaptive Hypotheses and Implications for Seed Dispersal Cipollini & Levey, The American Naturalist 150, no.33 (Jul 2015): 346–372.https://doi.org/10.1086/286069Martin L. Cipollini, Douglas J. Levey ANTIFUNGAL ACTIVITY OF SOLANUM FRUIT GLYCOALKALOIDS: IMPLICATIONS FOR FRUGIVORY AND SEED DISPERSAL, Ecology 78, no.33 (Apr 1997): 799–809.https://doi.org/10.1890/0012-9658(1997)078[0799:AAOSFG]2.0.CO;2

The development of secondary metabolites was examined in fruit pulp of Ilex opaca and Ilex verticillata, two bird-dispersed fruits with different patterns of persistence. Fruit pulp of both species contains phenolics, saponins, sclereids and calcium oxalate crystals. Unripe and ripe fruits were collected from six trees of each species from petal drop until after ripening and again after several hard freezes during 1987 and 1988. Pulp was analyzed for phenolic content using the Folin-Denis test and for saponins using hemolysis. Fruit skins were examined for lignification and quantity of sclereids. Development of phenolics showed similar patterns for both species over two years, while development of saponins was very different between the two species. Ilex verticillata had a sharp rise in mid-development while I. opaca had a constant level. In both species phenolics and saponins showed significant decreases coinciding with color change in fruits from green to red. Lignification of sclereids occur-red early in fruit development of both species. There were significant differences in quantity and position of sclereids in the fruit skins, with fruits of I. opaca having more sclereids closer to epidermal cells than those of I. verticillata.

Yellow-rumped Warblers (Dendroica coronata) and Tree Swallows (Tachycineta bicolor) are among a small group of birds in temperate North America that regularly eat waxy fruits. During the autumn, winter, and spring, these species feed extensively on fruits of the bayberry (Myrica spp.). Covering the pulp of these fruits is a solid, waxy material consisting primarily of saturated long-chain fatty acids. For most animals, saturated fatty acids are poorly assimilated (< 50%). Using H-3-glycerol triether as a nonabsorbable fat marker, we determined that Yellow-rumped Warblers are capable of high assimilation efficiences (> 80%) of bayberry wax when fed berries recoated with radioactive wax tracers. Efficient fatty-acid assimilation extends to berries coated with cetyl palmitate, a common marine, saturated wax ester (> 90%). The fatty-alcohol moiety of the marine wax was assimilated with a much lower efficiency (< 50%). A beeswax coating of the berries is assimilated with an efficiency of approximately 50%. Similar assimilation efficiencies of each wax are recorded for Tree Swallows feeding on recoated bayberries. Yellow Warblers (D. petechia) rejected recoated bayberries and exhibited little (< 5%) lipid assimilation of radiolabeled lipids. Yellow-rumped Warblers possess several gastrointestinal traits that permit efficient saturated-fat assimilation. Among these are an apparent retrograde reflux of intestinal contents to the gizzard, elevated gall-bladder and intestinal bile-salt concentration, and a slow gastrointestinal transit of dietary lipids. These gastrointestinal traits permit efficient assimilation of saturated fatty acids on bayberry fruits and may allow these small passerines to maintain more northerly wintering ranges than closely related species.

To quantify factors influencing the risk of fungal rot for vertebrate-dispersed fruits and to refine predictions concerning antifungal defense patterns, we examined physical, chemical, and phenological characteristics of ericaceous plants in New Jersey. In the field, three summer-ripening species had shorter persistence in the ripe state, shorter total retention times, and lower fungal resistance than three fall-ripening species. Summer fruits also had higher pulp carbohydrate content, lower fiber content, and (or) lower seed/pulp ratios. Whereas fungal colonization rates were somewhat lower during the ripening periods of summer species, fungal growth rates were higher owing to higher summer temperatures. In vitro fungal growth tests indicated only small effects of pulp nutrient content on fungal growth. We suggest that seasonal and chemical nutrient factors influencing risk of fungal rot for our study species are of minor significance relative to the degree to which these factors affect fruit removal by dispersers. We predict that owing to selection for high palatability, summer species should exhibit antifungal defenses with little or no antifrugivore effects (microbe-specific defenses). We also predict that because of consistently high removal rates (lower apparency), summer fruits should exhibit antifungal defenses less effective than those of fall species. Key words: antifungal defense, coadaptation, fruit rot, fruit nutrients, secondary chemistry, seed dispersal.

Chemical characteristics of antifungal extracts of ripe fruit pulp of six ericaceous plants that differ in fruit ripening phenology and other dispersal characteristics were examined. The antifungal activity of these fruits is particularly interesting because of contrasting effects of pulp secondary chemistry upon birds that disperse the seeds. Whereas extracts of summer-ripening fruit do not affect (or affect positively) the feeding rates of birds feeding on artificial-pulp media, extracts of fall-ripening fruit are very much a deterrent Results of fungal growth tests indicate that synergistic interactions of small phenolic constituents with small organic acids were most likely sources of antifungal activity for all but one species (Arctostaphylos uva-ursi), for which astringent polyphenolics and steroidal saponins were implicated. Fall-ripening fruit are apparently more of a deterrent to frugivores due to higher concentrations of organic acids in interaction with phenolic constituents, or higher concentrations of tannins and saponins. In conclusion, we stress the challenges that chemical synergism may present to chemical ecologists, and the importance of interactive effects of "primary" chemicals in plant defense.

We compared bird use of fruits of introduced and native plant species to explore the roles of coevolution, ecological fitting, and chance in shaping seed dispersal interactions. Of 45 bird-dispersed species recorded at three sites in central New Jersey, 15 (33%) were nonnative. In fall samples from seed traps and fecal droppings, introduced species accounted for 0.4-14% of fruit biomass overall and 3 - 30% of the biomass of low-quality fruits. Although absolute fruit use declined from fall to winter, relative use of introduced species increased seasonally to as high as half of winter fruit biomass. Heavy use of non-native fruits appears recent; introductions accounted for only 2% of plant species occurrences in fall and winter records of stomach contents for nine passerine species in New England and mid-Atlantic states between 1881 and 1950. Introduced fruits with fall maturation, low-quality pulp, and high durability now rival native species in fruit diets of birds in late fall arid winter. The success of introductions demonstrates coadaptation through ecological fitting of preadapted partners; nevertheless, the predominant use of introduced fruits after peak bird migration suggests that introduced fruits may be less well matched to local dispersal opportunities than native ones.

We examined the influence of differential reproductive frequency between the sexes on tertiary (phenotypic) sex ratios in the the dioecious tree Nyssa sylvatica (Nyssaceae). Reproduction was evaluated in relation to sex, size and canopy exposure using flowering data collected from 1229 marked trees over a four year period. For subsets of each population we used data on flower number, fruit crop size, fruit/flower ratios, and individual flower and fruit mass to compare biomass invested in reproductive structures of males and females. We also examined seasonal changes in stem nitrogen and soluble carbohydrate content in relation to flower and fruit production for trees of each sex. Our results indicate that: 1) Male-biased tertiary sex ratios could be explained by more frequent reproduction by male trees; 2) Estimated secondary sex ratios based on sums of all known males and females were not significantly different from 1:1; 3) Flowering frequency of males and females was significantly related to plant size (DBH) and exposure of the canopy to light; 4) Estimtes of reproductive biomass allocation ranged from 1.36 to 10.8 times greater for females relative to males; 5) Flower production was related to stem nutrient status for both sexes, but nutrient depletion and its effect on subsequent flowering was much more pronounced for female trees. We conclude that less frequent flowering by female trees may result from depletion of stored reserves, and that differential flowering frequency in N. sylvatica may ultimately reduce apparent sexual differences in the costs of reproduction.