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1.
Data Brief ; 57: 110895, 2024 Dec.
Article de Anglais | MEDLINE | ID: mdl-39314890

RÉSUMÉ

In Bangladesh, there are significant number of medicinal plants, but currently no comprehensive record of these valuable species is publicly available. Alarmingly, some of these plants are in a precarious state of endangerment. Therefore, we are creating a unique dataset of Bangladesh's rare, endangered, and threatened medicinal plants to support conservation efforts. It will help us to track and conserve endangered plant species, ensuring a more organized approach to research and preservation efforts. We conducted on-site visits to the National Botanical Garden and The Government Unani and Ayurvedic Medical College, capturing photographs of these plants in optimal sunlight conditions at various times of the day. This involved fieldwork, detailed image annotations, dataset organization, diversity augmentation, and contribution to the preservation of our natural heritage. We have collected a total of 16 types of rare and endangered medicinal plant leaf photos to create our unique dataset consisting of a total of 3494 images. This dataset will help researchers in biodiversity conservation through building efficient machine learning models and applying advanced machine learning techniques to identify rare and endangered medicinal plants.

2.
PhytoKeys ; 229: 185-213, 2023.
Article de Anglais | MEDLINE | ID: mdl-37546371

RÉSUMÉ

We present a review of Orchidaceae Juss. of the northern part of Kazakhstan, within the steppe, forest-steppe and semi-desert habitats of the country (Pavlodar, northern Kazakhstan, Kostanay, Akmola, Aktobe, West Kazakhstan, partially Karaganda and East Kazakhstan regions). The investigation is based on herbarium materials, literature data and field observations. We examined material from the following herbarium collections: LE, MW, TK, MHA, SVER, KUZ, ALTB, AA, NUR, KG, KSPI, NS, NSK, MOSP, ORIS, PPIU, totalling 288 herbarium specimens. The paper presents data in the form of revision, focusing on orchids of the northern part of Kazakhstan. It is accompanied by maps indicating localities, notes on habitat preferences, phenology and conservation status. A total of 25 species of 16 genera were recorded, of which eight are included in the Red Book of Kazakhstan (2014). According to our data, we propose to enlarge the number of protected orchids by adding the following nine species: Corallorhizatrifida, Epipactisatrorubens, Gymnadeniaconopsea, Hammarbyapaludosa, Herminiummonorchis, Liparisloeselii, Malaxismonophyllos, Neottiacamtschatea and Spiranthesaustralis. The most widespread species in the studied region are Dactylorhizaincarnata, D.umbrosa and Epipactispalustris. The rarest species (single locality only) are Epipactisatrorubens, E.helleborine, Epipogiumaphyllum, Hammarbyapaludosa and Herminiummonorchis.

3.
Plants (Basel) ; 12(13)2023 Jul 05.
Article de Anglais | MEDLINE | ID: mdl-37447118

RÉSUMÉ

Iris lacustris, a northern Great Lakes endemic, is a rare species known from 165 occurrences across Lakes Michigan and Huron in the United States and Canada. Due to multiple factors, including habitat loss, lack of seed dispersal, patterns of reproduction, and forest succession, the species is threatened. Early population genetic studies using isozymes and allozymes recovered no to limited genetic variation within the species. To better explore genetic variation across the geographic range of I. lacustris and to identify units for conservation, we used tunable Genotyping-by-Sequencing (tGBS) with 171 individuals across 24 populations from Michigan and Wisconsin, and because the species is polyploid, we filtered the single nucleotide polymorphism (SNP) matrices using polyRAD to recognize diploid and tetraploid loci. Based on multiple population genetic approaches, we resolved three to four population clusters that are geographically structured across the range of the species. The species migrated from west to east across its geographic range, and minimal genetic exchange has occurred among populations. Four units for conservation are recognized, but nine adaptive units were identified, providing evidence for local adaptation across the geographic range of the species. Population genetic analyses with all, diploid, and tetraploid loci recovered similar results, which suggests that methods may be robust to variation in ploidy level.

4.
Plants (Basel) ; 12(7)2023 Mar 28.
Article de Anglais | MEDLINE | ID: mdl-37050111

RÉSUMÉ

Many rare plant species lack up-to-date research about their reproductive ecology, which challenges effective in situ and ex situ conservation, particularly in the face of ongoing environmental and anthropogenic changes. For protected species, outdated and incomplete information also creates barriers to successful recovery planning and delisting. In this study, we gathered a range of reproductive metrics for the federally threatened and state endangered Florida endemic mint, Macbridea alba Chapman (Lamiaceae). We collected data at seven populations within Apalachicola National Forest (Florida, USA) and conducted germination trials to estimate reproductive potential. Additionally, we observed a previously undocumented lepidopteran seed predator for the species and confirmed the occurrence of vivipary. The seed set was low with less than 20% of flowers per inflorescence producing seed across populations; however, germination was high with more than 60% of seeds germinating in five of seven populations. When comparing our results to previous research conducted more than 20 years ago, the results were similar overall (i.e., germination, vivipary); however, new information emerged (i.e., herbivore pressure). As M. alba undergoes reassessment as a potential candidate for delisting from the Endangered Species Act (ESA) list, this information is critical for assessing recovery goals and decisions regarding the species' protected status. For recovery needs related to propagation and reintroduction, these results can inform future seed collection and propagation efforts for the species.

5.
Biodivers Data J ; 11: e113952, 2023.
Article de Anglais | MEDLINE | ID: mdl-38312337

RÉSUMÉ

Background: This study conducted a survey for establishing in-situ and ex-situ conservation measures for northern lineage plants that are vulnerable to climate change and for designating Forest Genetic Resource Reserve for 25 algific talus slope sites, which are specific areas of forest biodiversity. The survey was conducted in South Korea within a distance of 50 m to the east, west, north and south from the core area where wind blows to the algific talus slopes. The study was conducted once or twice per season from April 2016 to November 2021. New information: Vascular plants of 25 algific talus slope sites in South Korea included a total of 1,052 taxa of 125 families, 486 genera, 947 species, 23 subspecies, 75 variety and 7 forma. The maximum surveyed area was 0.09 km2, accounting for only 0.00014% of the 62,860 km2 forest area in Korea, but comprise 22.27% of the 4,724 species of vascular plants in Korea. The algific talus slopes are areas rich in forest biodiversity. Six taxa were categorized as endangered, including Paeoniaobovata Maxim. Sixty-seven taxa, including Astilboidestabularis (Hemsl.) Engl.; 58 taxa endemic to the Korean Peninsula, including Weigelasubsessilis (Nakai) L.H. Bailey; and 317 taxa of floristic target plants were categorized as rare plants in the Red list. Further, 181 taxa were identified as northern lineage plants and 32 taxa, including Sillaphytonpodagraria (H. Boissieu) Pimenov, were limestone area plants. Regarding alien plants, 75 taxa, including Oenotherabiennis L., were identified and the naturalization and urbanization rates were 7.13% and 12.12%, respectively. Plants specific to the phytogeography of the 25 algific talus slope sites in this study were Vacciniumvitis-idaea L., Rosakoreana Kom., SyringavillosaVahlsubsp.wolfii (C.K. Schneid.) Jin Y.Chen & D.Y. Hong, Lonicerachrysantha Turcz. ex Ledeb., Tephroserisflammea (Turcz. ex DC.) Holub, among others.

6.
Biodivers Data J ; 10: e85848, 2022.
Article de Anglais | MEDLINE | ID: mdl-36761563

RÉSUMÉ

This study surveyed the vascular flora present in 455 forest wetlands in South Korea to provide baseline data for conservation, management and monitoring and to support preparation for climate change. The survey period was from April 2015 to November 2019. The vascular flora of 455 forest wetlands were identified and were found to consist of 143 families, 582 genera, 1,246 species, 26 subsp., 104 var., 12 f. and 1,388 individual taxa. Eight taxa were identified as Grade II endangered wild plants, 220 taxa were identified as northern lineage plants of the Korean Peninsula, 66 taxa were endemic to the Korean Peninsula and 94 taxa were rare plants as designated by the Korea Forest Service. Amongst them, eight taxa were Critically Endangered species, 10 taxa were Endangered species, 31 taxa were Vulnerable species, 31 taxa were Least Concern species and 14 taxa were Data Deficient species. Further, 411 taxa were floristic target plants, of which 17 taxa were classified as grade V, 70 taxa as grade IV, 110 taxa as grade III, 90 taxa as grade II and 29 taxa as grade I. There were 64 invasive alien plant taxa. Eighteen of these species were classed as Widespread species, nine taxa were Serious Spread species, 13 taxa were Spread Risk species, 18 taxa were Spread Concern species and six taxa were Continuing Spread species. According to wetland preference, 152 taxa (11.0%) were obligate wetland plants, 138 taxa (9.9%) were facultative wetland plants and 177 (12.77%) taxa were facultative plants. Additionally, 198 taxa (14.3%) were facultative upland plants and 723 taxa (52.1%) were obligate upland plants.

7.
Plants (Basel) ; 9(12)2020 Dec 08.
Article de Anglais | MEDLINE | ID: mdl-33302534

RÉSUMÉ

The current investigation aimed to present an overview of the conservation of biological diversity of rare and endangered plant species. Methods of biodiversity conservation as well as several overview recommendations for the preservation of various rare species have been considered. An overview of the taxa included in the red book has been presented on the example of the Russian Federation. Global and local codes and classifiers of plant rarity were also presented. Future prospects for the conservation of biological diversity and the creation and development of bioresource collections have been considered.

8.
Am J Bot ; 106(6): 807-820, 2019 06.
Article de Anglais | MEDLINE | ID: mdl-31157408

RÉSUMÉ

PREMISE: In patterned fens, patches of short, sparse, species-rich vegetation often occur on substrates rich in precipitated carbonates near calcareous springheads, with taller, denser vegetation farther away. Boyer and Wheeler (1989) hypothesized that phosphorus co-precipitation near springheads limits plant productivity and coverage, and Givnish (1982) proposed that aggregations of rare, short-statured plant species might reflect their competitive restriction to sparsely covered microsites. METHODS: We tested these hypotheses by quantifying species distributions, leaf heights, plant coverage, community composition, and substrate and leaf chemistry of Eupatorium perfoliatum along a gradient of hydrology and geochemistry in a wetland complex in southeastern Wisconsin, USA, ranging from marl flats and fens on peat mounds near springheads to surrounding sedge meadows. RESULTS: Community composition was strongly correlated with a one-dimensional environmental gradient along which coverage and height increased moving downslope from marl flats, while soil carbonate, phosphorus immobilization capacity, and local species richness decreased, consistent with theory. Regionally rare species were short and restricted to sparsely covered microsites; within and among species, leaf height increased with local coverage. NPK tissue stoichiometry did not entirely support the Boyer-Wheeler hypothesis, although nitrogen limitation appeared strongest in sedge meadows. Shifts in stature and tissue chemistry of E. perfoliatum along the marl flat-sedge meadow gradient suggested that zinc toxicity may help limit coverage near springheads despite no significant change in soil zinc content. CONCLUSIONS: We propose a modified Boyer-Wheeler hypothesis to account for cascading effects of phosphorus co-precipitation near springheads on nitrogen fixation, nitrogen+phosphorus co-limitation, and zinc mobility.


Sujet(s)
Biodiversité , Eupatorium/physiologie , Sol/composition chimique , Zones humides , Eupatorium/croissance et développement , Azote/métabolisme , Phosphore/métabolisme , Dispersion des plantes , Dynamique des populations , Potassium/métabolisme , Wisconsin
9.
Ecol Appl ; 29(5): e01911, 2019 07.
Article de Anglais | MEDLINE | ID: mdl-31017349

RÉSUMÉ

In many of the world's arid regions there has been a dramatic increase in grazing pressure with herds of livestock sustained by the provision of artificial water points. In these systems it has been suggested that grazing-sensitive plant species will have contracted to refuges distant from water points where grazing impacts are low. This association was tested using a large data set of presence/absence records for rare plant species throughout the northeastern Australian arid zone. The presence records of only one of 45 species were statistically associated with lower grazing activity, as a function of distance-to-water, than the absence records. The field observation that this species is rarely grazed suggests it is not susceptible to grazing pressure. In general, the study supports assertions that populations of short-lived plants in drylands are resilient in the face of exaggerated livestock grazing because herbivores are not in sufficient densities to have an impact during the sporadic periods of high rainfall when plants can complete their life cycles. However, long-lived palatable species may be extinction-prone in grazed landscapes over long time frames if recruitment is curtailed by grazing.


Sujet(s)
Bétail , Eau , Animaux , Australie , Herbivorie , Plantes
10.
World J Microbiol Biotechnol ; 34(10): 156, 2018 Oct 04.
Article de Anglais | MEDLINE | ID: mdl-30284648

RÉSUMÉ

Microorganisms associated with plants have a great biotechnological potential, but investigations of these microorganisms associated with native plants in peculiar environments has been incipient. The objective of this study was to analyze the plant growth-promoting bacteria potential of cultivable bacteria associated with rare plants from the ferruginous rocky fields of the Brazilian Iron Quadrangle. The roots and rhizospheres of nine endemic plants species and samples of a root found in a lateritiric duricrust (canga) cave were collected, the culturable bacteria isolated and prospected for distinct biotechnological and ecological potentials. Out of the 148 isolates obtained, 8 (5.4%) showed potential to promote plant growth, whereas 4 (2.7%) isolates acted as biocontrol agents against Xanthomonas citri pathotype A (Xac306), reducing the cancrotic lesions by more than 60% when co-inoculated with this phytopathogen in Citrus sinensis plants. Moreover, other 4 (2.7%) isolates were classified as potential bioremediation agents, being able to withstand high concentrations of arsenite (5 mM As3+) and arsenate (800 mM As5+), by removing up to 35% and 15% of this metalloid in solution, respectively. These same four isolates had a positive influence on the growth of both the roots and the aerial parts when inoculated with tomato seeds in the soil contaminated with arsenic. This is the first time that an investigation highlights the potentialities of bacteria associated with rare plants of ferruginous rocky fields as a reservoir of microbiota of biotechnological and ecological interest, highlighting the importance of conservation of this area that is undergoing intense anthropic activity.


Sujet(s)
Bactéries/métabolisme , Phénomènes physiologiques bactériens , Biotechnologie , Développement des plantes/physiologie , Racines de plante/microbiologie , Rhizosphère , Amylases/métabolisme , Arséniates/métabolisme , Arsenic/métabolisme , Arsenic/pharmacologie , Arsénites/métabolisme , Bactéries/classification , Bactéries/effets des médicaments et des substances chimiques , Bactéries/génétique , Dépollution biologique de l'environnement , Biodiversité , Agents de lutte biologique , Brésil , Résistance aux substances , Engrais , Acide cyanhydrique/métabolisme , Acides indolacétiques/métabolisme , Solanum lycopersicum/croissance et développement , Solanum lycopersicum/microbiologie , Microbiote/physiologie , Fixation de l'azote , Peptide hydrolases/métabolisme , Phosphates/métabolisme , Maladies des plantes/microbiologie , Maladies des plantes/prévention et contrôle , Pathologie végétale , Racines de plante/composition chimique , ARN ribosomique 16S/génétique , Sidérophores/métabolisme , Sol/composition chimique , Microbiologie du sol , Polluants du sol/analyse , Polluants du sol/métabolisme , Xanthomonas/physiologie
11.
Annu Rev Entomol ; 62: 207-230, 2017 01 31.
Article de Anglais | MEDLINE | ID: mdl-27813663

RÉSUMÉ

Apparent feeding damage by insects on plants is often slight. Thus, the influences of insect herbivores on plant populations are likely minor. The role of insects on host-plant populations can be elucidated via several methods: stage-structured life tables of plant populations manipulated by herbivore exclusion and seed-addition experiments, tests of the enemy release hypothesis, studies of the effects of accidentally and intentionally introduced insect herbivores, and observations of the impacts of insect species that show outbreak population dynamics. These approaches demonstrate that some, but not all, insect herbivores influence plant population densities. At times, insect-feeding damage kills plants, but more often, it reduces plant size, growth, and seed production. Plant populations for which seed germination is site limited will not respond at the population level to reduced seed production. Insect herbivores can influence rare plant species and need to be considered in conservation programs. Alterations due to climate change in the distributions of insect herbivores indicate the possibility of new influences on host plants. Long-term studies are required to show if density-related insect behavior stabilizes plant populations or if environmental variation drives most temporal fluctuations in plant densities. Finally, insects can influence plant populations and communities through changing the diversity of nonhost species, modifying nutrient fluxes, and rejuvenating over mature forests.


Sujet(s)
Herbivorie , Insectes/physiologie , Plantes , Dynamique des populations , Animaux , Chaine alimentaire
12.
Conserv Biol ; 29(6): 1537-51, 2015 Dec.
Article de Anglais | MEDLINE | ID: mdl-26372611

RÉSUMÉ

We assessed the current status of plant conservation translocation efforts in China, a topic poorly reported in recent scientific literature. We identified 222 conservation translocation cases involving 154 species, of these 87 were Chinese endemic species and 101 (78%) were listed as threatened on the Chinese Species Red List. We categorized the life form of each species and, when possible, determined for each case the translocation type, propagule source, propagule type, and survival and reproductive parameters. A surprisingly large proportion (26%) of the conservation translocations in China were conservation introductions, largely implemented in response to large-scale habitat destruction caused by the Three-Gorge Dam and another hydropower project. Documentation and management of the translocations varied greatly. Less than half the cases had plant survival records. Statistical analyses showed that survival percentages were significantly correlated with plant life form and the type of planting materials. Thirty percent of the cases had records on whether or not individuals flowered or fruited. Results of information theoretic model selection indicated that plant life form, translocation type, propagule type, propagule source, and time since planting significantly influenced the likelihood of flowering and fruiting on the project level. We suggest that the scientific-based application of species conservation translocations should be promoted as part of a commitment to species recovery management. In addition, we recommend that the common practice of within and out of range introductions in nature reserves to be regulated more carefully due to its potential ecological risks. We recommend the establishment of a national office and database to coordinate conservation translocations in China. Our review effort is timely considering the need for a comprehensive national guideline for the newly announced nation-wide conservation program on species with extremely small populations, which is expected to stimulate conservation translocations for many species in the near future.


Sujet(s)
Conservation des ressources naturelles , Écosystème , Espèce en voie de disparition , Dispersion des plantes , Chine
13.
PhytoKeys ; (46): 45-60, 2015.
Article de Anglais | MEDLINE | ID: mdl-25829854

RÉSUMÉ

Cyaneakonahuanuiensis Sporck-Koehler, M. Waite, A.M. Williams, sp. nov., a recently documented, narrowly endemic species from the Hawaiian Island of O'ahu, is described and illustrated with photographs from the field. The closest likely relatives to the species, current conservation needs, and management future are discussed. It is currently known from 20 mature plants from two subpopulations and is restricted to a drainage below the Konahua-nui summit (K1), the highest summit of the Ko'olau Mountains, located on Windward O'ahu. It differs from all other Cyanea species by its combination of densely pubescent leaves, petioles, and flowers; sparsely pubescent to glabrous stems, long calyx lobes, and staminal column being adnate to the corolla.

14.
New Phytol ; 152(3): 511-520, 2001 Dec.
Article de Anglais | MEDLINE | ID: mdl-33862990

RÉSUMÉ

• The dependence of seeds of terrestrial orchids on specific fungi for germination provides a means of locating these fungi in the wild and to investigate the role of appropriate fungi in the germination of orchid seed and development of seedlings under natural field conditions. • Seed baits, comprising orchid (Caladenia arenicola) seed enclosed in fine nylon mesh, were placed at sample points along four transects through two orchid populations in bushland in Western Australia. Seed germination was scored and compared with adult orchid plant distribution and soil factors. • A small fraction of available seed (< 1%) germinated to a stage of tuber formation where survival over the subsequent dry season would have been possible. Germination increased in the vicinity of adult C. arenicola plants, but other factors, such as soil potassium levels and presence of leaf litter, were also correlated with seed germination. • The measurement of the spatial variability in germination events within an orchid habitat demonstrated the availability of new recruitment sites. This information is required to assess the natural recruitment capacity and the potential for orchid reintroduction in natural habitats.

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