scholarly journals Morphological and Genetic Diversities of Habenaria radiata (Orchidaceae) in the Kinki Area, Japan

2020 ◽  
Vol 22 (1) ◽  
pp. 311
Author(s):  
Tsutomu Tachibana ◽  
Yuki Nishikawa ◽  
Nakao Kubo ◽  
Seiji Takeda

Floral organs have evolved from leaves for reproduction, and the morphological analyses help to understand the plant diversity and evolution. Habenaria radiata (syn. Pecteilis radiata) is a terrestrial orchid living in wetlands in Japan, Russia, South Korea, and China. The habitats of this plant in Japan have been reduced because of environmental destruction and overexploitation, and thus it is on the Red List of Japan as a Near Threatened species. One of the three petals of the H. radiata flower is called a lip or labellum, which resembles a flying white bird, egret, or white heron, with its proposed function being to attract pollinators. To understand the diversity of H. radiata plants in different areas, we examined the lip morphology and phylogeny of populations from eight habitats in the Kinki area, Japan. The complex shapes of the lips were quantified and presented as a radar chart, enabling characterization of the morphological difference among populations. Phylogenetic analysis with microsatellite markers that we generated showed the variation of genetic diversity among populations, suggesting the different degrees of inbreeding, outbreeding, and vegetative propagation. Our approach offers a basic method to characterize the morphological and genetic diversity in natural populations.

Parasitology ◽  
2002 ◽  
Vol 125 (7) ◽  
pp. S51-S59 ◽  
Author(s):  
J. CURTIS ◽  
R. E. SORENSEN ◽  
D. J. MINCHELLA

Blood flukes in the genus Schistosoma are important human parasites in tropical regions. A substantial amount of genetic diversity has been described in populations of these parasites using molecular markers. We first consider the extent of genetic variation found in Schistosoma mansoni and some factors that may be contributing to this variation. Recently, though, attempts have been made to analyze not only the genetic diversity but how that diversity is partitioned within natural populations of schistosomes. Studies with non-allelic molecular markers (e.g. RAPDs and mtVNTRs) have indicated that schistosome populations exhibit varying levels of gene flow among component subpopulations. The recent characterization of microsatellite markers for S. mansoni provided an opportunity to study schistosome population structure within a population of schistosomes from a single Brazilian village using allelic markers. Whereas the detection of population structure depends strongly on the type of analysis with a mitochondrial marker, analyses with a set of seven microsatellite loci consistently revealed moderate genetic differentiation when village boroughs were used to define parasite subpopulations and greater subdivision when human hosts defined subpopulations. Finally, we discuss the implications that such strong population structure might have on schistosome epidemiology.


2015 ◽  
Vol 57 (3) ◽  
pp. 257-262
Author(s):  
Lasaro Teixeira FERREIRA ◽  
Aparecida Helena de Souza GOMES ◽  
Vera Lucia PEREIRA-CHIOCCOLA

Introduction: American tegumentary leishmaniasis (ATL) can be caused by Leishmania (Viannia) braziliensis complex. The evolution of ATL initially results in lesions and can develop into disseminated or diffuse forms. The genetic diversity of L. (V.) braziliensis in some endemic areas of Brazil has been poorly studied, such as in the state of São Paulo. This study analyzed the genetic diversity of L. (V.) braziliensis isolates collected from patients and dogs with LTA from the state of São Paulo. Methods: Leishmaniasis diagnosis was determined by PCR. The 132 biopsies were collected in different regions of Sao Paulo State, Brazil (36 municipalities). The genetic characterization of L. (V.) braziliensis isolates was tested by RFLP-PCR using DNA extracted from biopsies. The primer set amplified a specific region of Leishmania internal transcribed spacers of the ribosomal DNA locus. Results: Of the 132 samples, 52 (40%) were completely genotyped by RFLP-PCR (44 from human patients and eight from dogs). The results showed nine distinct patterns. The majority of the genotyped samples were from Sorocaba (30), and the others were distributed among 14 other municipalities. The first pattern was more frequent (29 samples), followed by pattern 2 (nine samples) and pattern 3 (three samples). Patterns 4, 6, 7, 8 and 9 were composed of two samples each and pattern 5 of one sample. Conclusion: These results suggest that polymorphic strains of L. (V.) braziliensis circulate in the state of São Paulo. These data agree with studies from other regions of Brazil, showing great variability among the natural populations of endemic foci.


2002 ◽  
Vol 68 (5) ◽  
pp. 2236-2245 ◽  
Author(s):  
K. M. Orcutt ◽  
U. Rasmussen ◽  
E. A. Webb ◽  
J. B. Waterbury ◽  
K. Gundersen ◽  
...  

ABSTRACT The genetic diversity of Trichodesmium spp. from natural populations (off Bermuda in the Sargasso Sea and off North Australia in the Arafura and Coral Seas) and of culture isolates from two regions (Sargasso Sea and Indian Ocean) was investigated. Three independent techniques were used, including a DNA fingerprinting method based on a highly iterated palindrome (HIP1), denaturing gradient gel electrophoresis of a hetR fragment, and sequencing of the internal transcribed spacer (ITS) of the 16S-23S rDNA region. Low genetic diversity was observed in natural populations of Trichodesmium spp. from the two hemispheres. Culture isolates of Trichodesmium thiebautii, Trichodesmium hildebrandtii, Trichodesmium tenue, and Katagnymene spiralis displayed remarkable similarity when these techniques were used, suggesting that K. spiralis is very closely related to the genus Trichodesmium. The largest genetic variation was found between Trichodesmium erythraeum and all other species of Trichodesmium, including a species of Katagnymene. Our data obtained with all three techniques suggest that there are two major clades of Trichodesmium spp. The HIP1 fingerprinting and ITS sequence analyses allowed the closely related species to be distinguished. This is the first report of the presence of HIP1 in marine cyanobacteria.


2003 ◽  
Vol 34 (6) ◽  
pp. 465-466 ◽  
Author(s):  
B. Fan ◽  
S.-L. Yang ◽  
B. Liu ◽  
M. Yu ◽  
S.-H. Zhao ◽  
...  

Author(s):  
Tanita Wein ◽  
Tal Dagan

Abstract Population bottlenecks leading to a drastic reduction of the population size are common in the evolutionary dynamics of natural populations; their occurrence is known to have implications for genome evolution due to genetic drift, the consequent reduction in genetic diversity and the rate of adaptation. Nevertheless, an empirical characterization of the effect of population bottleneck size on evolutionary dynamics of bacteria is currently lacking. Here we show that selective conditions have a stronger effect on the evolutionary history of bacteria in comparison to population bottlenecks. We evolved Escherichia coli populations under three different population bottleneck sizes (small, medium, large) in two temperature regimes (37 °C and 20 °C). We find a high genetic diversity in the large in comparison to the small bottleneck size. Nonetheless, the cold temperature led to reduced genetic diversity regardless the bottleneck size, hence, the temperature has a stronger effect on the genetic diversity in comparison to the bottleneck size. A comparison of the fitness gain among the evolved populations reveals a similar pattern where the temperature has a significant effect on the fitness. Our study demonstrates that population bottlenecks are an important determinant of bacterial evolvability; their consequences depend on the selective conditions and are best understood via their effect on the standing genetic variation.


2017 ◽  
Vol 41 (3) ◽  
pp. 255-262 ◽  
Author(s):  
Ana Veruska Cruz da Silva ◽  
Julie Anne Espíndola Amorim ◽  
Marina Ferreira da Vitória ◽  
Ana da Silva Ledo ◽  
Allivia Rouse Carregosa Rabbani

ABSTRACT The state of Sergipe is the largest mangaba producer, which is a fruit native to Brazil, and has cultural, social and economic importance in its area of occurrence. It is an endangered species due to human actions, and despite its economic potential, there are still no commercial plantations. The study was carried out in order to characterize trees, fruits and the genetic diversity of natural populations of mangaba in Sergipe, Brazil. Fruits from Abaís Beach/Estância (AB) presented, on average, twice the vitamin C content (414.81 mg of vit. C/100g), when compared with the others. The use of ISSR primers was efficient in estimating the genetic similarity of populations. The primers clustered the populations of mangaba according to their origin, which indicates the genetic diversity of mangaba and their isolation. The results can be used to guide the selection of individuals in situ and ex situ conservation actions of these genetic resources.


2018 ◽  
Vol 7 (4) ◽  
pp. 2179
Author(s):  
Sonali Ray ◽  
Nanda Dulal Paria

Seed and Seedling morphology of two species of Cupressaceae – Cupressus cashmeriana Royle ex Carriéreand Cryptomeria japonica (Thunb. Ex L.f.) D. Don have been studied using light microscope (LM) and scanning electron microscope (SEM). Both the species are categorized as Near Threatened (NT) in IUCN Red List Category (2013). For characterization of seed, different parameters like shape, size, base, apex, surface were considered. For the study of seedlings, the parameters like germination pattern, root, hypocotyl, number of paracotyledons, number and nature of first leaf and subsequent leaves have been characterized. The seed and seedling characters as studied in this investigation are important as taxonomic markers for identification purpose.


Pathogens ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 89
Author(s):  
Jiayu Li ◽  
Fuxian Yang ◽  
Ruobing Liang ◽  
Sheng Guo ◽  
Yaqiong Guo ◽  
...  

Cryptosporidiumfelis is an important cause of feline and human cryptosporidiosis. However, the transmission of this pathogen between humans and cats remains controversial, partially due to a lack of genetic characterization of isolates from cats. The present study was conducted to examine the genetic diversity of C. felis in cats in China and to assess their potential zoonotic transmission. A newly developed subtyping tool based on a sequence analysis of the 60-kDa glycoprotein (gp60) gene was employed to identify the subtypes of 30 cat-derived C. felis isolates from Guangdong and Shanghai. Altogether, 20 C. felis isolates were successfully subtyped. The results of the sequence alignment showed a high genetic diversity, with 13 novel subtypes and 2 known subtypes of the XIXa subtype family being identified. The known subtypes were previously detected in humans, while some of the subtypes formed well-supported subclusters with human-derived subtypes from other countries in a phylogenetic analysis of the gp60 sequences. The results of this study confirmed the high genetic diversity of the XIXa subtype family of C. felis. The common occurrence of this subtype family in both humans and cats suggests that there could be cross-species transmission of C. felis.


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