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Author(s):  
Kartika Senjarini ◽  
Lailly Nur Uswatul Hasanah ◽  
Miatin Alvin Septianasari ◽  
Muhammad Khalid Abdullah ◽  
Rike Oktarianti ◽  
...  

The presence of intraspecies variations of An. vagus later categorized as the subspecies of An. vagus vagus and An. vagus limosus, could be an obstacle to the identification process, which is an important step for malaria vector’s competence characterization. Based on morphological identification, those subspecies could be distinguished by the presences of pale scales in prehumeral and pale bands  in proboscis. The objective of this research was to compare subspecies complexes of An. vagus morphologically and molecularly using Internal Transcribed Spacer 2 (ITS2). Anopheles samples were collected from Bangsring, Banyuwangi. Their phylogenetic tree was constructed by using NJ method based on their ITS2 sequences. BLAST result showed that An. vagus vagus and An. vagus limosus were similar to An. vagus FJ654649.1 from East Java Indonesia and East Timor based on its 99% homology and their molecular distance. The Neighbour Joining (NJ) tree grouped those subspecies in one clade with a boostrap value of 82%. This subspeciation might be due to the different rates of evolution. ITS2 sequences of An. vagus vagus and An. vagus limosus were submitted to GenBank with the accession number of MW314227.1 and MW319822.1, respectively. Kemunculan variasi intraspesies An. vagus yang kemudian dikategorikan sebagai subspesies An. vagus vagus dan An. vagus limosus menjadi kendala dalam proses identifikasi yang merupakan langkah penting dalam menentukan kompetensi vektor malaria. Berdasarkan karakter morfologi, subspesies tersebut dibedakan dengan adanya sisik pucat pada bagian prehumeral dan pita pucat pada probosis. Penelitian ini bertujuan untuk membandingkan subspesies An. vagus secara morfologis dan molekuler menggunakan Internal Transcribed Spacer 2 (ITS2). Nyamuk Anopheles didapatkan dari Bangsring, Banyuwangi. Konstruksi pohon filogeni dilakukan berdasarkan sekuen ITS2 yang dianalisis menggunakan metode NJ. Hasil BLAST menunjukkan, ITS2 An. vagus vagus dan An. vagus limosus memiliki tingkat homologi 99% dan jarak evolusi molekuler terendah dengan An. vagus FJ654649.1 dari Jawa Timur Indonesia dan Timor Timur. Pohon NJ mengelompokkan subspesies tersebut dalam satu klade dengan nilai boostrap 82%. Hal ini dapat terjadi karena perbedaan kecepatan evolusi yang memungkinkan terjadinya subspesiasi. Urutan basa ITS2 dari An. vagus vagus dan An. vagus limosus telah didaftarkan ke GenBank dengan nomor aksesi MW314227.1 dan MW319822.1.


2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Tong Wang ◽  
Elizabeth M. Redman ◽  
Arianna Morosetti ◽  
Rebecca Chen ◽  
Sarah Kulle ◽  
...  

Abstract Background Gastrointestinal nematode (GIN) epidemiology is changing in many regions of the world due to factors such as global warming and emerging anthelmintic resistance. However, the dynamics of these changes in northern continental climate zones are poorly understood due to a lack of empirical data. Methods We studied the accumulation on pasture of free-living infective third-stage larvae (L3) of different GIN species from fecal pats deposited by naturally infected grazing cattle. The field study was conducted on three organic farms in Alberta, western Canada. Grass samples adjacent to 24 fecal pats were collected from each of three different pastures on each farm. Internal transcribed spacer-2 nemabiome metabarcoding was used to determine the GIN species composition of the harvested larvae. The rotational grazing patterns of the cattle ensured that each pasture was contaminated only once by fecal pat deposition. This design allowed us to monitor the accumulation of L3 of specific GIN species on pastures under natural climatic conditions without the confounding effects of pasture recontamination or anthelmintic treatments. Results In seven out of the nine pastures, grass L3 counts peaked approximately 9 weeks after fecal deposition and then gradually declined. However, a relatively large number of L3 remained in the fecal pats at the end of the grazing season. Nemabiome metabarcoding revealed that Cooperia oncophora and Ostertagia ostertagi were the two most abundant species on all of the pastures and that the dynamics of larval accumulation on grass were similar for both species. Daily precipitation and temperature across the whole sampling period were similar for most of the pastures, and multiple linear regression showed that accumulated rainfall 1 week prior to sample collection had a significant impact on the pasture L3 population, but accumulated rainfall 3 weeks prior to sample collection did not. Conclusions The results suggest that the pasture L3 population was altered by short-term microclimatic conditions conducive for horizontal migration onto grass. Overall, the results show the importance of the fecal pat as a refuge and reservoir for L3 of cattle GIN on western Canadian pastures, and provide an evidence base for the risk assessment of rotational grazing management in the region. Graphical Abstract


Phytotaxa ◽  
2021 ◽  
Vol 527 (1) ◽  
pp. 41-50
Author(s):  
LEI WANG ◽  
SHI-TONG LIU ◽  
YUN LIU ◽  
YING-MEI LIANG

Three rust fungi belonging to the genus Hyalopsora occurring on ferns were found in China. Hyalopsora minispora and H. tibetica are described as new species in this paper. Hyalopsora minispora can be distinguished from known species by its relatively small urediniospores (19.5–23.0 × 12.0–19.0 μm) with 4–6 scattered germ pores and amphispores in a common pustule. Hyalopsora tibetica is mainly characterized by urediniospores with 2–6 scattered germ pores and amphispores. Hyalopsora neocheilanthis is described and reported as a new record for China. The phylogenetic relationships of Hyalopsora species and related taxa were examined by comparing the sequences of their internal transcribed spacer 2 (ITS2) barcode and 28S rDNA gene segments. Hyalopsora is supported with strong bootstrap support and it differs from the two other fern-infecting genera viz. Milesina and Uredinopsis.


Planta Medica ◽  
2021 ◽  
Author(s):  
Iffat Parveen ◽  
Natascha Techen ◽  
Sara M. Handy ◽  
Jing Li ◽  
Charles Wu ◽  
...  

AbstractMorphological similarity within species makes the identification and authentication of Salvia species challenging, especially in dietary supplements that contain processed root or leaf powder of different sage species. In the present study, the species discriminatory power of 2 potential DNA barcode regions from the nuclear genome was evaluated in 7 medicinally important Salvia species from the family Lamiaceae. The nuclear internal transcribed spacer 2 and the exon 9 – 14 region of low copy nuclear gene WAXY coding for granule-bound starch synthase 1 were tested for their species discrimination ability using distance, phylogenetic, and BLAST-based methods. A novel 2-step PCR method with 2 different annealing temperatures was developed to achieve maximum amplification from genomic DNA. The granule-bound starch synthase 1 region showed higher amplification and sequencing success rates, higher interspecific distances, and a perfect barcode gap for the tested species compared to the nuclear internal transcribed spacer 2. Hence, these novel mini-barcodes generated from low copy nuclear gene regions (granule-bound starch synthase) that were proven to be effective barcodes for identifying 7 Salvia species have potential for identification and authentication of other Salvia species.


2021 ◽  
Vol 8 ◽  
Author(s):  
Matteo Garzia ◽  
Paolo Mariottini ◽  
Daniele Salvi ◽  
Giulia Furfaro

Mediterranean marine biodiversity is still underestimated especially for groups such as nudibranchs. The identification of nudibranchs taxa is challenging because few morphological characters are available and among them chromatic patterns often do not align with species delimitation. Molecular assessments helped unveiling cryptic diversity within nudibranchs and have been mostly based on mitochondrial markers. Fast evolving nuclear markers are much needed to complement phylogenetic and systematic assessments at the species and genus levels. Here, we assess the utility of the nuclear Internal Transcribed Spacer 2 (ITS2) to delimit species in the eolid nudibranchs using both primary and secondary structures. Comparisons between the variation observed at the ITS2 and at the two commonly used mitochondrial markers (COI and 16S) on 14 eolid taxa from 10 genera demonstrate the ability of ITS2 to detect congeneric, closely related, species. While ITS2 has been fruitfully used in several other mollusc taxa, this study represents the first application of this nuclear marker in nudibranchs.


2021 ◽  
Vol 20 (1) ◽  
Author(s):  
James M. Hodge ◽  
Andrey A. Yurchenko ◽  
Dmitriy A. Karagodin ◽  
Reem A. Masri ◽  
Ryan C. Smith ◽  
...  

Abstract Background The malaria mosquito Anopheles punctipennis, a widely distributed species in North America, is capable of transmitting human malaria and is actively involved in the transmission of the ungulate malaria parasite Plasmodium odocoilei. However, molecular diagnostic tools based on Internal Transcribed Spacer 2 (ITS2) of ribosomal DNA are lacking for this species. Anopheles punctipennis is a former member of the Anopheles maculipennis complex but its systematic position remains unclear. Methods In this study, ITS2 sequences were obtained from 276 An. punctipennis specimens collected in the eastern and midwestern United States and a simple and robust Restriction Fragment Length Polymorphism approach for species identification was developed. The maximum-likelihood phylogenetic tree was constructed based on ITS2 sequences available through this study and from GenBank for 20 species of Anopheles. Results The analysis demonstrated a consistent ITS2 sequence length and showed no indications of intragenomic variation among the samples based on ITS2, suggesting that An. punctipennis represents a single species in the studied geographic locations. In this study, An. punctipennis was found in urban, rural, and forest settings, suggesting its potential broad role in pathogen transmission. Phylogeny based on ITS2 sequence comparison demonstrated the close relationship of this species with other members of the Maculipennis group. Conclusions This study developed molecular tools based on ITS2 sequences for the malaria vector An. punctipennis and clarified the phylogenetic position of the species within the Maculipennis group.


2021 ◽  
Vol 75 (6) ◽  
pp. 418
Author(s):  
Kartika Senjarini ◽  
Muhammad Abdullah ◽  
Nuril Azizah ◽  
Miatin Septianasari ◽  
Ahmad Tosin ◽  
...  

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