A5004470591- Plant and animal studies
- Plant Parasitism and Resistance
- Ecology and Vegetation Dynamics Studies
- Fern and Epiphyte Biology
- Plant and Fungal Species Descriptions
- Botany, Ecology, and Taxonomy Studies
- Plant Diversity and Evolution
- Plant Pathogens and Fungal Diseases
- Species Distribution and Climate Change
- Insect and Pesticide Research
- Flowering Plant Growth and Cultivation
- Insect and Arachnid Ecology and Behavior
- Plant Reproductive Biology
- Botany and Geology in Latin America and Caribbean
- Plant Pathogens and Resistance
- Yeasts and Rust Fungi Studies
- Plant Physiology and Cultivation Studies
- Genetic diversity and population structure
- Botanical Research and Applications
- Biochemical and biochemical processes
- Biological Control of Invasive Species
- Plant and soil sciences
- Wildlife Ecology and Conservation
- Forest Insect Ecology and Management
- Scarabaeidae Beetle Taxonomy and Biogeography
University of Puerto Rico at Río Piedras
2010-2025
University of Puerto Rico System
2016-2025
University College Cork
2007
Smithsonian Institution
1982-2007
Universidad Nacional de Colombia
2007
California Lutheran University
2005
Smithsonian Tropical Research Institute
1987
University of California, Riverside
1986
Florida State University
1979-1983
Humboldt State University
1977-1980
The great taxonomic diversity of the Orchidaceae is often attributed to adaptive radiation for specific pollinators driven by selection outcrossing. However, when one looks beyond product process, evidence less than overwhelming. We explore this problem discussing relevant aspects orchid biology and asking which reproduction explain intricate pollination mechanisms diversification family. reaffirm that orchids are primarily limited, severity affected resource constraints. Fruit set higher in...
Abstract Orchidaceae show remarkable diversity in pollination strategies, but how these strategies vary globally is not entirely clear. To identify regions and taxa that are data-rich lend themselves to rigorous analyses or data-poor need attention, we introduce a global database of orchid reproductive biology. Our contains > 2900 species representing all subfamilies 23 24 tribes. We tabulated information on habit, breeding systems, means pollinator attraction the identity...
Orchids constitute one of the most spectacular radiations flowering plants. However, their origin, spread across globe, and hotspots speciation remain uncertain due to lack an up-to-date phylogeographic analysis. We present a new Orchidaceae phylogeny based on combined high-throughput Sanger sequencing data, covering all five subfamilies, 17/22 tribes, 40/49 subtribes, 285/736 genera, c. 7% (1921) 29 524 accepted species, use it infer geographic range evolution, diversity, patterns by adding...
Fruit production in interoparous flowering plants can be limited by a variety of conditions that need not mutually exclusive nor immediately evident. We examined short— and long—term constraints to fruit Puerto Rican population the infrequently pollinated orchid Epidendrum ciliare. Average natural maturation rate ranged from 5 15% over 4 yr. To evaluate limitations production, pollinations were augmented for randomly chosen experimental portion two consecutive years. During this period, only...
All orchids have an obligate relationship with mycorrhizal symbionts. Most orchid fungi are classified in the form‐genus Rhizoctonia . This group includes anamorphs of Tulasnella , Ceratobasidium and Thanatephorus can be according to number nuclei young cells (multi‐, bi‐, uninucleate). From nine Puerto Rican we isolated 108 ‐like fungi. Our isolates were either bi‐ or uninucleate, first report uninucleate as endophytes. We sequenced internal transcribed spacer (ITS) region nuclear ribosomal...
The proportionally low fruit set observed in many epiphytic tropical orchids usually has been attributed to insufficient pollination; for example, the orchid Ionopsis utricularioides, a twig epiphyte, offers no floral rewards, is rarely visited, and set. To determine what factors limit fruiting this species, we assessed effects of resources, pollinator service, pollen parentage, quantity using greenhouse field studies which individual plants were followed over two flowering seasons. Plants...
Seasonal and geographic relationships, host pollinator specificities are examined for indications of interdependency in the orchid-euglossine bee interaction. The orchids dependent on bees pollination, their flowering seasonality corresponds well with peak activity pollinators. However, there is little evidence that these fragrance hosts. tap majority euglossine species individuals services during any given season, but most those temporarily lack orchid hosts persist area, continually emerge...
Abstract Orchids parasitize their mycorrhizal fungi and are dependent on them for seed germination. Controversy reigns over how specific the association is in tropical species. Although there little experimental evidence to support any viewpoint, some variation known exist. We compared specificity performance two phylogenetically related epiphytic orchids from Puerto Rico, Tolumnia variegata Ionopsis utricularioides (Oncidiinae) by integrating techniques: phylogenetic analysis of based...
Seasonal changes in species richness, composition, and abundance of male euglossine bees were determined by weekly censusing individuals attracted to 16 chemical baits. Bee populations monitored for >1 yr the lowland tropical moist forest seasonally dry Barro Colorado Island (BCI), Panama. Male also censused one every 4 wk at three nearby mainland sites, two low elevation, a middle—elevation locality. Among sites bee communities varied little; dominance ranks, species' phenological...
Tropical orchids constitute the greater part of orchid diversity, but little is known about their obligate mycorrhizal relationships. The specificity these interactions and associated fungal distributions could influence diversity. We investigated tropical epiphytic Ionopsis utricularioides across an extensive geographical range. DNA ITS sequence variation was surveyed in both plants fungi. Phylogeographic relationships were estimated for Orchid functional outcomes determined through vitro...
In the Guanica Forest Reserve, Puerto Rico, Encyclia krugii lacks pollinator rewards, is visited infrequently and matures few fruits. Hand-pollinations showed that flowers are self- incompatible. 22 censuses, I monitored number of flowers, fruits, vegetative shoots, active inflorescences were produced over two years. During first 20 all open 43 randomly assigned, experimental plants cross-pollinated. Fruiting these was compared with 37 pollinated controls to determine if pollination limited....
The nectar-foraging behavior of male euglossine bees (Hymenoptera: Apidae) was studied at a population Calathea latifolia (Marantaceae) on Barro Colorado Island, Panama, for two weeks. Several marked males Exaerete smaragdina and Euglossa imperialis foraged C. daily basis. Immigration rates were low, the site fidelity high. Selection inflorescences by individuals not random. learned specific locations which they consistently ignored nearby inflorescences. However, all in bee's repertoire...
ABSTRACT Orchid diversity, distribution and host specificity were examined in a tropical watershed the Luquillo Experimental Forest of Puerto Rico. Eleven orchid species occur area. The low diversity is attributed to island isolation large-scale hurricane disturbances. Pleurothallis ruscifolia Maxillaria coccinea by far most abundant area occurred on largest number zones. None orchids specific or zone specialists although preferences for hosts vertical zones encountered. Only 8.2% 426 trees...
Genetic drift can play an important role in population differentiation, particularly when effective sizes are small and gene flow is limited. Such conditions suspected to be common the species-rich Orchidaceae. We investigated likelihood of genetic natural populations three endemic species Lepanthes (Orchidaceae) from Puerto Rico. estimated size, Ne, using ecologically based methods. Two estimates were on variance reproductive potential third was coalescence time. All Ne usually <40%...
Variation in choices and preferences for fragrances are examined a large portion of the euglossine bee assemblages Barro Colorado Island (BCI) Cerro Campana, Panama. Census data were obtained from year-long baiting program utilizing 16 chemical attractants. Interand intraspecific variation fragrance occurred. Within sites, species overlapped considerably, but each was attracted to unique set baits. For some species, infrequently visited chemicals differed among sites. The five baits...
Abstract Aim Understanding the factors driving diversity of alien and native species on islands is crucial for predicting spread proposing management practices to protect unique biodiversity that often occurs in insular ecosystems. The main objective this study was evaluate whether plant respond similarly natural biogeographic human‐related drivers. Location Lesser Antilles, Caribbean. Methods We compiled a dataset with verified status occurring 15 across Antilles. assessed relationship...
Extraordinary floral variation is common among some orchids that employ deception to attract pollinators. This may be maintained by frequency-dependent selection where rare phenotypes are preferred. Over a 2-yr period, 1993-1994, we monitored the reproductive success of Tolumnia variegata, an obligately outcrossing epiphytic orchid, at three localities in Puerto Rico differed pollinator service. Plants varied morphology and fragrance characteristics. Artificial arrays varying frequencies...
Variation in floral fragrance compounds might be a pollination strategy that disrupts associative learning processes and inhibits pollinator's ability to recognize non‐rewarding flowers. Floral fragrances of the nectarless, moth‐pollinated Epidendrum ciliare (Orchidaceae) were obtained from plants Puerto Rico Virgin Islands. Fragrances collected by passive diffusion on tenax adsorbent analyzed using gas chromatography mass spectrometry (GUMS). The analysis was performed at six different...
Comparettia falcata is an epiphytic, neotropical orchid that produces nectar as a pollinator reward. In Puerto Rico, C. allogamous and pollinated by the endemic hummingbird Chlorostilbon maugaeus. Autogamous pollinations are possible, but may result in reduced fruit set. For 1989 1990 flowering seasons, probability of pollinarium removals natural increased with individual inflorescence display size. However, frequency effective visits was independent phenology both years. A positive...
Aim We obtain biogeographical patterns based on the distributions of shared orchid species Caribbean. These are used to define zones. then analyse concordance between distributional with ecological and physical features islands. Location use recorded 49 islands Greater, Lesser, southern Antilles, Bahamas. Three continental areas included: Florida (North America), Yucatan (Central Guianas (South America). Methods a parsimonious analysis that produces best arrangements taxa among areas. The...