scholarly journals Why Variation in Flower Color May Help Reproductive Success in the Endangered Australian Orchid Caladenia fulva

2021 ◽  
Vol 12 ◽  
Author(s):  
Georgia Basist ◽  
Adrian G. Dyer ◽  
Jair E. Garcia ◽  
Ruth E. Raleigh ◽  
Ann C. Lawrie
Keyword(s):  
Seed Viability ◽  
Its Region ◽  
Flower Color ◽  
Ex Situ ◽  
Seed Collection ◽  
Artificial Pollination ◽  
Flower Color Polymorphism ◽  
Open Woodland ◽  
Color Variants

Caladenia fulva G.W. Carr (Tawny Spider-orchid) is a terrestrial Australian endangered orchid confined to contiguous reserves in open woodland in Victoria, Australia. Natural recruitment is poor and no confirmed pollinator has been observed in the last 30 years. Polymorphic variation in flower color complicates plans for artificial pollination, seed collection and ex situ propagation for augmentation or re-introduction. DNA sequencing showed that there was no distinction among color variants in the nuclear ribosomal internal transcribed spacer (ITS) region and the chloroplast trnT-trnF and matK regions. Also, authentic specimens of both C. fulva and Caladenia reticulata from the reserves clustered along with these variants, suggesting free interbreeding. Artificial cross-pollination in situ and assessment of seed viability further suggested that no fertility barriers existed among color variants. Natural fruit set was 15% of the population and was proportional to numbers of the different flower colors but varied with orchid patch within the population. Color modeling on spectral data suggested that a hymenopteran pollinator could discriminate visually among color variants. The similarity in fruiting success, however, suggests that flower color polymorphism may avoid pollinator habituation to specific non-rewarding flower colors. The retention of large brightly colored flowers suggests that C. fulva has maintained attractiveness to foraging insects rather than evolving to match a scarce unreliable hymenopteran sexual pollinator. These results suggest that C. fulva should be recognized as encompassing plants with these multiple flower colors, and artificial pollination should use all variants to conserve the biodiversity of the extant population.

scholarly journals Pollination Ecology and Breeding System of Delphinium Occidentale

1993 ◽  
Vol 17 ◽  
pp. 87-90
Author(s):  
Ron Scogin
Keyword(s):  
Flower Color ◽  
Pollination Ecology ◽  
Seed Collection ◽  
Local Populations ◽  
Balanced Polymorphism ◽  
Flower Color Polymorphism ◽  
Tall Larkspur ◽  
Alternative Hypotheses ◽  
Flower Form ◽  
Delphinium Occidentale

Delphinium occidentale Nutt. (Ranunculaceae), the tall larkspur, occurs sporatically as isolated local populations in moist locations at lower and middle elevations of Grand Teton National Park. Individual plants of this species exhibit flowers which occur as one of three distinct color morphs and which occur mixed in the local populations. The three floral morphs are 1) plants exhibiting the most familiar, uniformly dark purple pigmented flower form, 2) plants exhibiting an all white, nonpigmented, albino form, and 3) plants whose flowers are intermediate in form between the extremes of 1) and 2), a semi-albino form which exhibits normally pigmented petals, but white, nonpigmented sepals. The occurrence of mixed, polymorphic populations of D. occidentale floral morphs can be rationalized by two alternative hypotheses: 1. A stable, balanced polymorphism exists among the three morphs. This polymorphism is actively maintained by selective pressures, probably on some aspect of the reproductive biology (perhaps pollination ecology) of the floral morphs, or 2. The distribution of polymorphs is merely a founder effect, reflecting the distribution of morphs present in the seed collection which initially established the colonizing population. The research undertaken during 1993 represents an effort to discriminate between these alternative explanations of flower color polymorphism in D. occidentale.

Lactarius guangdongensis sp. nov. (Russulaceae, Russulales), a species of Lactarius sect. Deliciosi growing with a vulnerable five-needle pine, Pinus kwangtungensis

Phytotaxa ◽  
2019 ◽  
Vol 393 (3) ◽  
pp. 278
Author(s):  
YING HAN ◽  
CUN-ZHU LIANG ◽  
PEI-GUI LIU ◽  
JORINDE NUYTINCK ◽  
XIANG-HUA WANG
Keyword(s):  
New Species ◽  
South China ◽  
Ex Situ Conservation ◽  
Phylogenetic Analyses ◽  
Its Region ◽  
Morphological Characters ◽  
Ex Situ ◽  
Dehydrogenase Gene ◽  
A New Species

Lactarius sect. Deliciosi is a group of ectomycorrhizal mushrooms showing high host specificity with trees of Pinaceae and more rarely Fagales. A new species of this section, L. guangdongensis, is described from South China. This new species has the smallest basidiocarps (pileus 1–3 cm) in the section. The pure orange basidiocarps with faint greenish discoloration are similar to those of Abies-associated L. abieticola and L. laeticolor and Pinus-associated L. vividus. The subdistant lamellae and absence of pleuromacrocystidia can be used as valid characters for this species. It grows with Chinese national protected plant Pinus kwangtungensis and might be one of the very few species that form symbiosis with five-needle pines. Phylogenetic analyses of the ITS region and glyceraldehyde-3-phosphate dehydrogenase gene (gpd) show that L. guangdongensis clearly diversified from its relatives and look-alikes and probably represents an early diverging lineage in the section. Molecular and morphological characters provided in this study will be useful for in situ and ex situ conservation of P. kwangtungensis in the future.

scholarly journals Seed germination of Carex lainzii Luceño, E. Rico & T. Romero: An endemic Spanish endangered species

2019 ◽  
Vol 20 (3) ◽  
pp. 704-711
Author(s):  
KAROLINE APARECIDA FELIX RIBEIRO ◽  
CRISTIAN MADEIRA DE MEDEIROS ◽  
JOSÉ ÁNGEL SÁNCHEZ-AGUDO ◽  
JOSÉ SÁNCHEZ-SÁNCHEZ
Keyword(s):  
Seed Germination ◽  
Endangered Species ◽  
Ex Situ Conservation ◽  
Seed Viability ◽  
Potassium Nitrate ◽  
Ex Situ ◽  
Cold Stratification ◽  
Different Temperatures ◽  
Two Populations

Abstract. Ribeiro KAF, Madeira de Medeiros C, Agudo JAS, Sánchez JS. 2019. Seed germination of Carex lainzii Luceño, E. Rico & T. Romero: An endemic Spanish endangered species. Biodiversitas 20: xxxx. Strategies to halt the decline of biodiversity include: in-situ and ex-situ conservation, the latter already considered at the global level essential in conservation programs. The results of the germinative responses of Carex lainzii Luceño, E. Rico & T. Romero (Cyperaceae), an endemic Spanish endangered species, are presented in this work, to different trials carried out in the laboratory with seeds harvested in the two known populations of that community. Treatments with and without 0.2% potassium nitrate (KNO3) were tested for four, six and eight months in cold stratification at 5 °C in two germination chambers at different temperatures (22/10 °C and 27/15 °C with a photoperiod of 12/12 hours). The results indicate that there is a large difference in germination rates between the two populations. The use of KNO3 did not increase germination rates in any case, but differences were found between periods of cold stratification, with six months being the most effective. On the other hand, the germination rates of both populations remain low (17.58% and 2%) compared to the obtained rate of seed viability. With this first approach to the understanding of the germination requirements of C. lainzii, it becomes clear that new essays are needed to obtain better results, in order to effectively implement the protection plans of C. lainzii populations.

Making the case for plant diversity

2010 ◽  
Vol 21 (1) ◽  
pp. 1-4 ◽  
Author(s):  
Paul Smith ◽  
John Dickie ◽  
Simon Linington ◽  
Robin Probert ◽  
Michael Way
Keyword(s):  
Plant Species ◽  
Plant Diversity ◽  
Natural Capital ◽  
Full Range ◽  
Ex Situ ◽  
Plant Science ◽  
Millennium Ecosystem Assessment ◽  
Seed Collection ◽  
Ecosystem Assessment

AbstractThe Millennium Ecosystem Assessment estimates that between 60,000 and 100,000 plant species are threatened with extinction–equivalent to around one-quarter of the total number of known plant species. Why should we care? There are a number of reasons. The first is that these plants may be useful to us in unknown ways. Secondly, ecology has taught us that resilience is found in diversity. Thirdly, we should be saving plant species from extinction because we can–there is no technological reason why any plant species should become extinct. Where we can't protect and manage plant diversity in situ, we should be employing ex situ conservation techniques, ranging from seed banks to habitat restoration. The Millennium Ecosystem Assessment describes such interventions as ‘techno-gardening’. This is not an abstract concept–it is already a reality in the majority of man-managed landscapes. In this context the perception of ex situ conservation as simply a back-up strategy for in situ conservation is mistaken. We are all involved in ex situ conservation to some degree, from cultivating our back gardens, to farming, to management of protected areas. Ex situ conservation should be seen as a complementary approach to in situ conservation and on the same spectrum. Kew's Millennium Seed Bank Partnership, comprising more than 120 plant science institutions in 50 countries, epitomizes this philosophy in action. We work actively on every seed collection we bank, finding out how useful it is and how we can grow it to enable human innovation, adaptation and resilience. Challenges remain at the policy level; for example, the need to factor-in the value of natural capital to development decision making, and better defining a role for public-sector science. At the technical level, also, there is much to do. Perhaps the greatest technical challenges relate to the restoration and management of complex, self-sustaining habitats or species assemblages. If we are to techno-garden effectively, in order to maintain ecosystem services and sustain biodiversity, then a multidisciplinary approach will be required. Many plant science institutions have recognized this and are becoming engaged increasingly in restoration activities and in situ management. Ultimately, humanity's ability to innovate and adapt is dependent on our having access to the full range of plant species and the alleles they contain.

Seed mass and elevation explain variation in seed longevity of Australian alpine species

2018 ◽  
Vol 28 (4) ◽  
pp. 319-331 ◽  
Author(s):  
Annisa Satyanti ◽  
Adrienne B. Nicotra ◽  
Thomas Merkling ◽  
Lydia K. Guja
Keyword(s):  
Seed Mass ◽  
Seed Viability ◽  
Plant Conservation ◽  
Seed Longevity ◽  
Ex Situ ◽  
Accelerated Ageing ◽  
Alpine Regions ◽  
Australian Alps ◽  
Alpine Species

AbstractConserving alpine ecosystems and the plant communities they contain using ex situ conservation requires an understanding of seed longevity. Knowledge of seed longevity may determine the effectiveness of ex situ seed banking for alpine plant conservation, and may provide insight into plant recruitment in situ. We sought to determine the influence of elevation and climatic variables, as well as plant and seed traits, on the seed longevity of 57 species inhabiting a unique biome, (sub-)alpine regions of mainland Australia. Seed longevity was estimated using controlled accelerated ageing tests to determine the time taken for seed viability to fall by 50%. We found that, across the study species, like alpine seeds elsewhere in the world, Australian alpine seeds are relatively short-lived and overall shorter-lived than Australian plants in general. Seed mass and elevation explained most of the variation in seed longevity among the Australian alpine species considered. Species with larger seed mass, and collections made at higher elevations, were found to have relatively short-lived seeds. Phylogeny, however, explained very little of the variation in longevity. Our results suggest that viability testing for Australian alpine seeds in ex situ seed banks should be conducted with shorter intervals than for the non-alpine flora. This study highlights how seed longevity in the Australian Alps is not dictated primarily by evolutionary lineage but rather by a complex combination of environmental variables and intrinsic seed characteristics. Potential implications for conservation ex situ and in situ in the context of climate change are discussed.

An in situ and ex situ TEM study of the formation of thin cobalt silicide films by molecular beam epitaxy on the silicon (100) surface

1988 ◽  
Vol 46 ◽  
pp. 884-885
Author(s):  
D. Loretto ◽  
J. M. Gibson ◽  
S. M. Yalisove ◽  
R. T. Tung
Keyword(s):  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
Defect Density ◽  
High Vacuum ◽  
Ultra High Vacuum ◽  
Ex Situ ◽  
Metal Base ◽  
In Situ Experiments ◽  
Potential Applications

The cobalt disilicide/silicon system has potential applications as a metal-base and as a permeable-base transistor. Although thin, low defect density, films of CoSi2 on Si(111) have been successfully grown, there are reasons to believe that Si(100)/CoSi2 may be better suited to the transmission of electrons at the silicon/silicide interface than Si(111)/CoSi2. A TEM study of the formation of CoSi2 on Si(100) is therefore being conducted. We have previously reported TEM observations on Si(111)/CoSi2 grown both in situ, in an ultra high vacuum (UHV) TEM and ex situ, in a conventional Molecular Beam Epitaxy system.The procedures used for the MBE growth have been described elsewhere. In situ experiments were performed in a JEOL 200CX electron microscope, extensively modified to give a vacuum of better than 10-9 T in the specimen region and the capacity to do in situ sample heating and deposition. Cobalt was deposited onto clean Si(100) samples by thermal evaporation from cobalt-coated Ta filaments.

The use of transmission and analytical electron microscopy in studying reactions and phase transformations in thin film

1993 ◽  
Vol 51 ◽  
pp. 842-843
Author(s):  
K. Barmak
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Phase Transformations ◽  
Analytical Electron Microscopy ◽  
Ex Situ ◽  
Multilayer Thin Films ◽  
Absolute Concentration ◽  
Analytical Electron ◽  
Deposition Step

Generally, processing of thin films involves several annealing steps in addition to the deposition step. During the annealing steps, diffusion, transformations and reactions take place. In this paper, examples of the use of TEM and AEM for ex situ and in situ studies of reactions and phase transformations in thin films will be presented.The ex situ studies were carried out on Nb/Al multilayer thin films annealed to different stages of reaction. Figure 1 shows a multilayer with dNb = 383 and dAl = 117 nm annealed at 750°C for 4 hours. As can be seen in the micrograph, there are four phases, Nb/Nb3-xAl/Nb2-xAl/NbAl3, present in the film at this stage of the reaction. The composition of each of the four regions marked 1-4 was obtained by EDX analysis. The absolute concentration in each region could not be determined due to the lack of thickness and geometry parameters that were required to make the necessary absorption and fluorescence corrections.

Transmission Electron Microscopy of Epitaxial silicides grown by ultra high vacuum deposition

1989 ◽  
Vol 47 ◽  
pp. 462-463
Author(s):  
D. Loretto ◽  
J. M. Gibson ◽  
S. M. Yalisove
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Electron Diffraction ◽  
High Vacuum ◽  
High Energy ◽  
Energy Electron ◽  
Ultra High Vacuum ◽  
Ex Situ ◽  
Transmission Electron

The silicides CoSi2 and NiSi2 are both metallic with the fee flourite structure and lattice constants which are close to silicon (1.2% and 0.6% smaller at room temperature respectively) Consequently epitaxial cobalt and nickel disilicide can be grown on silicon. If these layers are formed by ultra high vacuum (UHV) deposition (also known as molecular beam epitaxy or MBE) their thickness can be controlled to within a few monolayers. Such ultrathin metal/silicon systems have many potential applications: for example electronic devices based on ballistic transport. They also provide a model system to study the properties of heterointerfaces. In this work we will discuss results obtained using in situ and ex situ transmission electron microscopy (TEM).In situ TEM is suited to the study of MBE growth for several reasons. It offers high spatial resolution and the ability to penetrate many monolayers of material. This is in contrast to the techniques which are usually employed for in situ measurements in MBE, for example low energy electron diffraction (LEED) and reflection high energy electron diffraction (RHEED), which are both sensitive to only a few monolayers at the surface.

Atomic Layer Deposition of LiF and Lithium Ion Conducting (AlF3)(LiF)x Alloys Using Trimethylaluminum, Lithium Hexamethyldisilazide and Hydrogen Fluoride

2017 ◽  
Author(s):  
Younghee Lee ◽  
Daniela M. Piper ◽  
Andrew S. Cavanagh ◽  
Matthias J. Young ◽  
Se-Hee Lee ◽  
...  
Keyword(s):  
Lithium Ion ◽  
Atomic Layer ◽  
Mass Gain ◽  
Alloy Film ◽  
Ex Situ ◽  
X Ray ◽  
Layer Deposition ◽  
Ion Conducting ◽  
Good Agreement

<div>Atomic layer deposition (ALD) of LiF and lithium ion conducting (AlF<sub>3</sub>)(LiF)<sub>x</sub> alloys was developed using trimethylaluminum, lithium hexamethyldisilazide (LiHMDS) and hydrogen fluoride derived from HF-pyridine solution. ALD of LiF was studied using in situ quartz crystal microbalance (QCM) and in situ quadrupole mass spectrometer (QMS) at reaction temperatures between 125°C and 250°C. A mass gain per cycle of 12 ng/(cm<sup>2</sup> cycle) was obtained from QCM measurements at 150°C and decreased at higher temperatures. QMS detected FSi(CH<sub>3</sub>)<sub>3</sub> as a reaction byproduct instead of HMDS at 150°C. LiF ALD showed self-limiting behavior. Ex situ measurements using X-ray reflectivity (XRR) and spectroscopic ellipsometry (SE) showed a growth rate of 0.5-0.6 Å/cycle, in good agreement with the in situ QCM measurements.</div><div>ALD of lithium ion conducting (AlF3)(LiF)x alloys was also demonstrated using in situ QCM and in situ QMS at reaction temperatures at 150°C A mass gain per sequence of 22 ng/(cm<sup>2</sup> cycle) was obtained from QCM measurements at 150°C. Ex situ measurements using XRR and SE showed a linear growth rate of 0.9 Å/sequence, in good agreement with the in situ QCM measurements. Stoichiometry between AlF<sub>3</sub> and LiF by QCM experiment was calculated to 1:2.8. XPS showed LiF film consist of lithium and fluorine. XPS also showed (AlF<sub>3</sub>)(LiF)x alloy consists of aluminum, lithium and fluorine. Carbon, oxygen, and nitrogen impurities were both below the detection limit of XPS. Grazing incidence X-ray diffraction (GIXRD) observed that LiF and (AlF<sub>3</sub>)(LiF)<sub>x</sub> alloy film have crystalline structures. Inductively coupled plasma mass spectrometry (ICP-MS) and ionic chromatography revealed atomic ratio of Li:F=1:1.1 and Al:Li:F=1:2.7: 5.4 for (AlF<sub>3</sub>)(LiF)<sub>x</sub> alloy film. These atomic ratios were consistent with the calculation from QCM experiments. Finally, lithium ion conductivity (AlF<sub>3</sub>)(LiF)<sub>x</sub> alloy film was measured as σ = 7.5 × 10<sup>-6</sup> S/cm.</div>

A New Method of Wafer Level Plan View TEM Sample Preparation by DualBeam

2008 ◽  
Author(s):  
Hyoung H. Kang ◽  
Michael A. Gribelyuk ◽  
Oliver D. Patterson ◽  
Steven B. Herschbein ◽  
Corey Senowitz
Keyword(s):  
Sample Preparation ◽  
Ex Situ ◽  
Wafer Level ◽  
Cross Sectional ◽  
Plan View ◽  
Manufacturing Line ◽  
Transmission Electron ◽  
Thin Lamella ◽  
Preparation Techniques

Abstract Cross-sectional style transmission electron microscopy (TEM) sample preparation techniques by DualBeam (SEM/FIB) systems are widely used in both laboratory and manufacturing lines with either in-situ or ex-situ lift out methods. By contrast, however, the plan view TEM sample has only been prepared in the laboratory environment, and only after breaking the wafer. This paper introduces a novel methodology for in-line, plan view TEM sample preparation at the 300mm wafer level that does not require breaking the wafer. It also presents the benefit of the technique on electrically short defects. The methodology of thin lamella TEM sample preparation for plan view work in two different tool configurations is also presented. The detailed procedure of thin lamella sample preparation is also described. In-line, full wafer plan view (S)TEM provides a quick turn around solution for defect analysis in the manufacturing line.

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