scholarly journals A Demographic Model of an Endangered Florida Native Bromeliad (Tillandsia utriculata)

2020 ◽  
Vol 6 (1) ◽  
Author(s):  
Zoe Brookover ◽  
Alexandra Campbell ◽  
Brian Christman ◽  
Sydney Davis ◽  
Erin Bodine
Keyword(s):  
Germination Rate ◽  
Model Analysis ◽  
Population Viability ◽  
Leaf Length ◽  
Conservation Strategies ◽  
Demographic Model ◽  
Population Reduction ◽  
Viable Population ◽  
Specific Conservation ◽  
Myakka River

The large, long-lived, epiphytic bromeliad Tillandsia utriculata is currently listed as state-endangered in Florida due to significant population reduction from predation by an invasive weevil, Metamasius callizona. We have developed a novel demographic model of a population of T. utriculata in Myakka River State Park (MRSP) in Sarasota, Florida using a stage-structured matrix model. Analysis of the model revealed conditions for population viability over a variety of parameter scenarios. Model analysis showed that without weevil predation the minimum germination rate required for population viability is low (4–16%), and that given a viable population at structural equilibrium we would expect to find <1% of the population in flower or post-flowering each year and, at most, about 10% of rosettes with longest leaf length (LLL) > 15 cm in flower or post-flowering each year. Additionally, the model presented here provides a basis for further analyses which explore specific conservation strategies.

Optimizing conservation strategies for Mexican free-tailed bats: a population viability and ecosystem services approach

2014 ◽  
Vol 24 (1) ◽  
pp. 63-82 ◽  
Author(s):  
Ruscena Wiederholt ◽  
Laura López-Hoffman ◽  
Colleen Svancara ◽  
Gary McCracken ◽  
Wayne Thogmartin ◽  
...  
Keyword(s):  
Ecosystem Services ◽  
Population Viability ◽  
Conservation Strategies

scholarly journals The Effects of Salinity on Hibiscus syriacus and H. hamabo Seed Germination

HortScience ◽  
1995 ◽  
Vol 30 (4) ◽  
pp. 899C-899
Author(s):  
Moo R. Huh ◽  
Beyoung H. Kwack ◽  
Leonard P. Perry
Keyword(s):  
Seed Germination ◽  
Saline Solution ◽  
Germination Rate ◽  
Leaf Length ◽  
Distilled Water ◽  
Fresh Weight ◽  
Petri Dishes ◽  
Hibiscus Syriacus

In this experiment, the effects of salinity from 0.0%, 0.5%, 1.0%, and 5.0 % NaCl on Hibiscus syriacus L. and Hibiscus hamabo Sieb. & Zucc. seed germination with various temperature and Ca treatments was investigated in petri dishes with 10 ml of distilled water or with the appropriate saline solution. At 11 days after treatment, the highest germination rate was obtained at 20C with H. syriacus and 25C with H. hamabo without NaCl and Ca treatments. At 25C, only H. hamabo seeds germinated with 1% NaCl, with dry and fresh weight increasing as Ca concentration increased. With 0.5% NaCl treatment, the germination rate of H. hamabo and H. syriacus increased as Ca concentrations (0.0, 13.35, and 133.5 mM) increased. Without NaCl treatments, hypocotyl and leaf length and width of H. syriacus were longer than those of H. hamabo; with NaCl treatments, the inverse was true.

scholarly journals Growth Characteristics of Adenophora triphylla var. japonica Hara Seedlings as Affected by Growing Medium

Plants ◽  
2019 ◽  
Vol 8 (11) ◽  
pp. 466
Author(s):  
Hye Ri Lee ◽  
Hyeon Min Kim ◽  
Hyeon Woo Jeong ◽  
Gam Gon Kim ◽  
Chae In Na ◽  
...  
Keyword(s):  
Production System ◽  
Germination Rate ◽  
Leaf Length ◽  
Growth Characteristics ◽  
Plant Production ◽  
Photon Flux ◽  
Photon Flux Density ◽  
Root Surface Area ◽  
Root Tips ◽  
Closed Type

Adenophora triphylla var. japonica Hara is a highly valued medicinal plant that is used to treat or prevent bronchitis, cough, cancer, and obesity. However, there has been no study on the production of Adenophora triphylla var. japonica Hara seedlings in a closed-type plant production system (CPPS). This study was conducted to examine the growth characteristics of Adenophora triphylla var. japonica Hara seedlings as affected by different growing media. The seeds were sown on a 128-cell plug tray filled with urethane sponges (US), LC grow foam (LC), rockwool (RW), or terra-plugs (TP). The seedlings were cultured for a duration of 54 days under temperature 25 ± 1°C, a photoperiod of 12/12 h (light/dark), and light intensity of 180 µmol·m−2·s−1 photosynthetic photon flux density provided by RB LEDs (red:blue = 8:2) in a closed-type plant production system (CPPS). The germination rate of Adenophora triphylla var. japonica Hara was significantly highest in the TP. Also, seedling shoot growth indicators of plant height, leaf length, leaf width, number of leaves, fresh weight (FW), and dry weight (DW) of the shoot, and leaf area were markedly the greatest in the TP and the lowest in the US. The SPAD (soil-plant analysis development) value was higher in the TP and US than in the LC or RW. In addition, the seedling root growth characteristics of total root length, root surface area, root volume, and number of root tips were significantly greatest in the TP. Moreover, the maximum root diameter, FW and DW of roots were the greatest in the TP. In conclusion, the results suggest that TP are viable for the growth development of Adenophora triphylla var. japonica Hara seedlings.

scholarly journals Ranunculus constantinopolitanus Bitkisinin Bazı Bitkisel Özellikleri, Besleme Değeri ve Tohumlarına Ait Çimlenme Oranlarının Belirlenmesi

2020 ◽  
Vol 8 (7) ◽  
pp. 1553-1558
Author(s):  
Erdal Çaçan ◽  
İhsan Arslan
Keyword(s):  
Nutritive Value ◽  
Germination Rate ◽  
Dry Weight ◽  
Leaf Length ◽  
Toxic Substances ◽  
City Center ◽  
Protein Ratio ◽  
Plant Seeds ◽  
Number Of Leaves ◽  
Plant Characteristics

This study was carried out to determine the plant characteristics, nutritive value and seed germination rate of the Ranunculus constantinopolitanus plant, which is found intensely in meadow-pasture areas and can have toxic effects on animals when consumed. The plant material of this study consists of 50 Ranunculus constantinopolitanus plants collected by random sampling method from the meadow area in Çayağzı village located in Bingöl city center in 2018. Plant length of Ranunculus constantinopolitanus 39-70 cm, stem diameter 1.83-5.53 mm, number of flowers in the plant 3-17, number of leaves in the plant 4-10, leaf length 3-7 cm, leaf width 4-8 cm, plant dry weight 0.75-3.33 grams, stalk ratio in plant 35.1-86.5%, leaf ratio in plant 3.9-42.7%, flower ratio in plant 4.0-43.4%, number of fruit in plant 4.0-11.0, number of achene in fruit 18.0-36.0, number of achene per plant 26-180 and thousand seed weight of achene varied between 4.31-5.03 grams. The dry matter ratio of Ranunculus constantinopolitanus 90.5-90.6%, crude protein ratio 13.1-13.4%, ADF ratio 34.9-35.9%, NDF ratio 47.3-48.9%, ADP ratio 0.33-0.37%, Ca ratio 1.16-1.22%, Mg ratio 0.37-0.38%, P ratio 0.26-0.27% and K ratio varied between 0.94-0.97%. As a result of the germination test with plant seeds, it was determined that 87 seeds germinate at the end of the 21st day, and the total germination rate was 21.8%. Detection of toxic substances and other nutrients contained in this plant with future studies will provide better recognition of this plant.

scholarly journals Germination and Early Seedling Growth of Rare Zamia spp. in Organic and Inorganic Substrates: Advancing Ex Situ Conservation Horticulture

HortScience ◽  
2010 ◽  
Vol 45 (4) ◽  
pp. 679-683 ◽  
Author(s):  
Claudia Calonje ◽  
Chad Husby ◽  
Michael Calonje
Keyword(s):  
Germination Rate ◽  
Leaf Length ◽  
Dry Forest ◽  
Silica Sand ◽  
Ex Situ ◽  
Inorganic Substrates ◽  
Early Seedling ◽  
Survival And Growth ◽  
Propagation Methods ◽  
Germination And Growth

Improved propagation methods greatly benefit conservation of rare cycads. Appropriate substrate conditions, especially excellent root aeration, are crucial to successful cultivation of most cycads. Typical cycad substrates include substantial portions of organic materials that will decompose over time, reducing drainage and increasing water retention. In this study, two inorganic substrates, arcillite (Turface® MVP®) and coarse silica sand, and one mixed cycad substrate (with organic and inorganic components) were evaluated for germination and growth of three rare Zamia species: Z. fairchildiana L.D. Gómez, Z. cunaria Dressler & D.W. Stev., and Z. aff. portoricensis Urb. over a period of 14 months from seed sowing. Substrate type affected leaves per seedling and leaf length. These factors also varied by species as did taproot length and germination rate. There were also significant interactions between substrate and species for caudex diameter and leaf variables, likely reflecting ecological differences among the species, two of which are from rainforest habitats and one from dry forest. All three substrates performed adequately for germination, survival, and growth of Zamia. Turface® and possibly the silica sand likely require additional watering to improve their performance as cycad substrates.

scholarly journals Population Viability and Conservation Strategies for the Eurasian Black Vulture (Aegypius monachus) in Southeast Europe

Animals ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 124
Author(s):  
Kyriakos G. Dimitriou ◽  
Evangelos G. Kotsonas ◽  
Dimitrios E. Bakaloudis ◽  
Christos G. Vlachos ◽  
Graham J. Holloway ◽  
...  
Keyword(s):  
Extinction Risk ◽  
Wind Farms ◽  
Population Viability ◽  
Supplementary Feeding ◽  
Conservation Strategies ◽  
Southeast Europe ◽  
Feeding Site ◽  
Black Vulture ◽  
Demographic Fluctuations ◽  
Site Network

The Eurasian Black Vulture is a globally threatened raptor that in Southeast Europe only occurs in an isolated population in Greece. We examined the population viability for the species under demographic fluctuations and conservation scenarios. The current population showed no possibility of extinction for the next 100 years. However, simulated scenarios showed that the most important factor affecting the viability of the species was medium and high poisoning, leading to 94.8% and 100% probability of extinction, respectively. Furthermore, high reduction of supplementary feeding highlighted an 18.6% extinction possibility. Also, a high increase of wind farms in the area may result in 17.4% extinction possibility. Additionally, the non-establishment of the feeding station in 1987 in the study area would have resulted in an extinction risk of 7%. The species can be translocated to the Olympus National Park by releasing 80 juveniles over 10 years. The implementation of the conservation scenarios concerning the establishment of a supplementary feeding site network, and the reintroduction of the Eurasian Black Vulture in its historic range, along with the elimination of threats posed by poisoning, low food availability, and wind farms would increase the probability of the species persistence and allow the population to become a source for dispersal across Southeast Europe.

Modelling the impact of predation on reintroductions of bridled nailtail wallabies.

1995 ◽  
Vol 22 (2) ◽  
pp. 163 ◽  
Author(s):  
H McCallum ◽  
P Timmers ◽  
. Hoyle.S
Keyword(s):  
Population Viability Analysis ◽  
Population Viability ◽  
Predator Prey ◽  
Viability Analysis ◽  
Standard Population ◽  
Viable Population ◽  
Almost All ◽  
The Impact ◽  
Number Of Individuals ◽  
Simple Stochastic Model

Predation by introduced foxes and cats is generally thought to be the main reason for the poor success rate of macropod reintroductions on the Australian mainland. Predator-prey theory suggests that predation may have particularly severe impacts on very small populations, especially if a more common primary prey species is present (such as the rabbit). Thus, a sufficiently large reintroduction may overcome predation and succeed where a smaller one would fail. The minimum viable population would, however, be much larger than that predicted by standard population-viability analysis. We use a simple stochastic model based upon the bridled nailtail wallaby to explore this possibility. Even very small amounts of predation (2-4 individuals per six months) can be sufficient to cause reintroductions of up to 50 animals to fail. No clear threshold population size beyond which reintroductions will succeed is evident and, for a given mean, the probability distribution of predation has a very limited impact on the success of reintroductions. In almost all circumstances, a single reintroduction of a given size is preferable to multiple reintroductions of the same total number of individuals.

scholarly journals Eco-geographic variation of common wild rice - Oryza ru?pogon Griff. in Sri Lanka

2018 ◽  
Vol 1 (02) ◽  
pp. 36-43
Author(s):  
S Sandamal ◽  
A Tennakoon ◽  
D Ratnasekera ◽  
DABN Amarasekera ◽  
B Marambe
Keyword(s):  
Sri Lanka ◽  
Phenotypic Diversity ◽  
Flag Leaf ◽  
Morphological Diversity ◽  
Population Based ◽  
Leaf Length ◽  
Oryza Rufipogon ◽  
Conservation Strategies ◽  
Leaf Angle ◽  
Flag Leaf Length

Wild species of rice (Oryza) have superior agronomic characteristics to be incorporated in rice breeding programs worldwide.  Population studies of wild relatives of rice in Sri Lanka has not being well documented despite a few of attempts. In the present study, phenotypic diversity of Oryza rufipogon populations exist in Sri Lanka were characterized based on nine quantitative morphological traits. Populations (P1, P2, P3, P4 and P5) were established in a common-garden and were characterized. The results revealed moderate phenotypic diversity among O. rufipogon populations studied. However, flag leaf length and awn length were the most variable traits while plant height, flag leaf angle, flag leaf panicle neck length and spikelet angle were the least variable traits. O. rufipogon can be simply distinguished using flag leaf length and width, panicle branching type and distance from panicle base to lowest spikelet insertion. The dendrogram results indicated that four main clusters are at a similarity level of 98.73, showing the diversely related populations with a high identity based on higher similarity values. P1 and P2 populations grouped together by forming the first cluster. The second, third and fourth clusters consisted of P3, P5 and P4 populations, respectively. One population from first cluster and P3, P5 and P4 populations can be used for conservation. This study highlights the phenotypic diversity of O. rufipogon populations existing in Sri Lanka across the geographic locations and Knowledge on such morphological diversity provides opportunities to design conservation strategies and the potentials of using particular population based on breeding objectives.  

Genetic and morphologic variation in Phyllodoce empetriformis and Phyllodoce glanduliflora (Ericaceae) in Mount Rainier National Park, Washington

2001 ◽  
Vol 79 (2) ◽  
pp. 179-191
Author(s):  
Regina M Rochefort ◽  
David L Peterson
Keyword(s):  
Genetic Diversity ◽  
National Park ◽  
Leaf Length ◽  
Stem Length ◽  
Leaf Width ◽  
Conservation Strategies ◽  
Allozyme Analysis ◽  
Mount Rainier ◽  
Mount Rainier National Park ◽  
Morphologic Variation

Genetic and morphological diversity of Phyllodoce empetriformis (Sw.) D. Don and Phyllodoce glanduliflora (hook.) Cov. were surveyed in Mount Rainier National Park in the Cascade Mountains of Washington State. Paired populations at high and low elevations were sampled at three study areas between 1720- and 2451-m elevation. Allozyme analysis of four polymorphic loci indicates high levels of genetic diversity within populations (P. empetriformis = 94.2% and P. glanduliflora = 93.4% of total diversity) and significant differences in allele frequencies among populations and study areas. Individual populations are composed of multiple clones with high ratios of local to widespread genotypes. The proportion of distinguishable clones ranges from 32 to 83% within individual populations. Within individual populations, 18-67% of genotypes were restricted to one population. Patterns of morphologic variation, estimated through measurements of leaf width, leaf length, stem extension, and plant height paralleled those displayed by allozyme analysis. Significant differences were found in leaf width and stem length for P. empetriformis and among greenhouse populations for leaf width (P. empetriformis) and leaf length (P. glanduliflora). Species conservation strategies for Phyllodoce should concentrate on the maintenance of within-population levels of diversity, protection of adjacent populations, and protection of safe sites for recruitment of new populations.Key words: conservation, Ericaceae, genetic diversity, morphologic variation, Phyllodoce.

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