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The Challenges Of Growing Orchids From Seeds For Conservation: An Assessment Of Asymbiotic Techniques, Devani Jolman, Martín I. Batalla, Alexis Hungerford, Pryce Norwood, Noah Tait, Lisa E. Wallace Jan 2022

The Challenges Of Growing Orchids From Seeds For Conservation: An Assessment Of Asymbiotic Techniques, Devani Jolman, Martín I. Batalla, Alexis Hungerford, Pryce Norwood, Noah Tait, Lisa E. Wallace

Biological Sciences Faculty Publications

Lewis Knudson first successfully germinated orchid seeds asymbiotically on artificial medium in 1922. While many orchid species have since been grown asymbiotically, the tremendous variation in how species respond to artificial medium and growth conditions ex situ has also become apparent in the past century. In this study, we reviewed published journal articles on asymbiotic orchid seed germination to provide a summary of techniques used and to evaluate if these differ between terrestrial and epiphytic species, to identify areas where additional research is needed, and to evaluate whether asymbiotic germination could be used more often in ex situ conservation. We …


Endless Symbioses Most Intricate, W. John Hayden Jul 2016

Endless Symbioses Most Intricate, W. John Hayden

Biology Faculty Publications

Orchids, such as our Wildflower of the Year for 2016, Downy Rattlesnake Plantain (Goodyera pubescens) (Fig. 1), exemplify the interconnectedness of life on Earth. As would be the case for many kinds of plants, pollination comes readily to mind as a prominent example of mutualistic symbiosis. Downy Rattlesnake Plantain is pollinated by bumblebees and other native bees. The bees gain nectar and the orchid gets an efficient means to move pollen from one flower to another; each organism gains benefit from the interaction, the very definition of mutualism. Pollination by bees is widespread among the orchids, but there …


Jewels Of The Orchidaceae, W. John Hayden Apr 2016

Jewels Of The Orchidaceae, W. John Hayden

Biology Faculty Publications

To temperate-zone plant enthusiasts, the orchid family seems more than a little strange. On the one hand, native orchids grow wild without assistance from people, they are rooted in the soil, and they survive freezing cold winter temperatures. On the other hand, the tropical orchids that we encounter are ornamental plants, pampered by their human caregivers, cultured indoors in pots filled with fir bark or other media designed to mimic the plants’ natural epiphytic habit, and, as a group, these ornamental tropical orchids have essentially zero tolerance to frost. Of course, their flowers, fruits, and seeds define them all as …


2016 Virginia Wildflower Of The Year: Downy Rattlesnake Plantain, Goodyera Pubescens, W. John Hayden Jan 2016

2016 Virginia Wildflower Of The Year: Downy Rattlesnake Plantain, Goodyera Pubescens, W. John Hayden

Biology Faculty Publications

Regardless of season, Downy Rattlesnake Plantain is a delight to encounter in the woods of Virginia. This evergreen orchid is a perennial rhizomatous herb of the forest floor. The horizontal rhizomes, usually covered lightly by leaf litter, bear roots at intervals and terminate in a rosette of leaves. Leaves are alternate, somewhat crowded together, and only slightly elevated above ground level. Leaf blades are ovate, 3–8 cm long, and 1.5–3 cm wide, often of varying size within a rosette. Leaves are present year-round, bluish-green, with prominent white veins; on each leaf, a broad midvein is flanked by two smaller veins …


Molecular Phylogenetics Of Vandeae (Orchidaceae) And The Evolution Of Leaflessness, Barbara Carlsward, W. Whitten, Norris Williams, Benny Bytebier Jan 2006

Molecular Phylogenetics Of Vandeae (Orchidaceae) And The Evolution Of Leaflessness, Barbara Carlsward, W. Whitten, Norris Williams, Benny Bytebier

Faculty Research & Creative Activity

Members of tribe Vandeae (Orchidaceae) form a large, antropical clade of horticulturally important epiphytes. Monopodial leafless members of Vandeae have undergone extreme eduction in habit and represent a novel adaptation to the canopy environment in tropical Africa, Asia, and America. To study the evolution of monopodial leaflessness, molecular and structural evidence was used to generate phylogenetic hypotheses for Vandeae. Molecular analyses used sequence data from ITS nrDNA, trnL-F plastid DNA, and matK plastid DNA. Maximum parsimony analyses of these three DNA regions each supported two subtribes within monopodial Vandeae: Aeridinae and a combined Angraecinae þ Aerangidinae. Adding structural characters to …


Molecular Phylogenetics Of Vandeae (Orchidaceae) And The Evolution Of Leaflessness, Barbara S. Carlsward, W. Mark Whitten, Norris H. Williams, Benny Bytebier Jan 2006

Molecular Phylogenetics Of Vandeae (Orchidaceae) And The Evolution Of Leaflessness, Barbara S. Carlsward, W. Mark Whitten, Norris H. Williams, Benny Bytebier

Faculty Research & Creative Activity

Members of tribe Vandeae (Orchidaceae) form a large, antropical clade of horticulturally important epiphytes. Monopodial leafless members of Vandeae have undergone extreme eduction in habit and represent a novel adaptation to the canopy environment in tropical Africa, Asia, and America. To study the evolution of monopodial leaflessness, molecular and structural evidence was used to generate phylogenetic hypotheses for Vandeae. Molecular analyses used sequence data from ITS nrDNA, trnL-F plastid DNA, and matK plastid DNA. Maximum parsimony analyses of these three DNA regions each supported two subtribes within monopodial Vandeae: Aeridinae and a combined Angraecinae þ Aerangidinae. Adding structural characters to …


Origin And Conservation Genetics Of Threatened Ute Ladies’-Tresses, Spiranthes Diluvialis (Orchidaceae), Allen L. Szalanski, Gerry Steinauer, Richard Bischof, Jessica Lynn Petersen Jan 2001

Origin And Conservation Genetics Of Threatened Ute Ladies’-Tresses, Spiranthes Diluvialis (Orchidaceae), Allen L. Szalanski, Gerry Steinauer, Richard Bischof, Jessica Lynn Petersen

Department of Animal Science: Faculty Publications

The Ute ladies’-tresses, Spiranthes diluvialis, is listed as a threatened orchid in west-central United States by the Federal government. Information on its origin and patterns of genetic variation is needed to develop effective conservation strategies for this species. DNA sequencing and polymerase chain reaction–restriction fragment length polymorphism (PCR-RFLP) was used to evaluate genetic variation and structure of 23 populations of S. diluvialis. In addition, four congeneric species were analyzed to determine possible origins of the putative allotetraploid S. diluvialis. DNA sequencing and PCR-RFLP analysis of the nuclear ribosomal internal transcribed spacer (ITS) and mitochondrial and chloroplast DNA …


Osmophores, Floral Features, And Systematics Of Stanhopea (Orchidaceae), Kenneth J. Curry, Lorraine M. Mcdowell, Walter S. Judd, William Louis Stern May 1991

Osmophores, Floral Features, And Systematics Of Stanhopea (Orchidaceae), Kenneth J. Curry, Lorraine M. Mcdowell, Walter S. Judd, William Louis Stern

Faculty Publications

The floral fragrance glands (osmophores) of 18 species of Stanhopea and Sievekingia were examined through a series of developmental studies at light and electron microscope levels including late bud stages through postanthesis. Various characters were identified to be of potential systematic value and were recorded for each species. These characters included: texture of the osmophore surface, number of distinct cell layers comprising the osmophore, nature of lipid inclusions in osmophore cells, and presence or absence of plastoglobuli in osmophore amyloplasts. These characters were combined with traditional features of floral lip morphology for cladistic analysis. Sievekingia was the postulated outgroup. Stanhopea …