Evidence for natural interspecific hybridization between the Australian bass (Macquaria novemaculeata) and estuary perch (M. colonorum)

1999 ◽  
Vol 50 (7) ◽  
pp. 661 ◽  
Author(s):  
Dean R. Jerry ◽  
Tarmo A. Raadik ◽  
Stuart C. Cairns ◽  
Peter R. Baverstock
Keyword(s):  
Species Identification ◽  
Interspecific Hybridization ◽  
Interspecific Hybrids ◽  
Natural Populations ◽  
Morphological Characters ◽  
Morphometric Study ◽  
Gradient Gel Electrophoresis ◽  
Breeding Programmes ◽  
Temperature Gradient Gel Electrophoresis ◽  
Allozyme Loci

Australian bass (Macquaria novemaculeata) and estuary perch (M. colonorum) are very similar in their morphology, use of habitat and geographical distribution. Following the capture from four Victorian rivers of specimens possessing species-diagnostic attributes intermediate to the two taxa, an allozyme electrophoresis and morphometric study was undertaken to investigate the possibility that these individuals were the results of interspecific hybridization. Two allozyme loci were found to be useful in species identification and were used to confirm that the individuals in question were indeed interspecific hybrids. The presence of hybrids was further supported by univariate and multivariate analysis of morphological characters. Temperature-gradient gel electrophoresis on mtDNA control- region fragments demonstrated that where interspecific hybrids were identified, the maternal parent species was M. novemaculeata. The demonstration that M. novemaculeata and M. colonorum can hybridize in natural populations emphasizes the importance of correct species identification in breeding programmes to prevent the liberation of large numbers of interspecific hybrids.

Allozyme differentiation among populations, stands, and cohorts in Monterey pine

1986 ◽  
Vol 16 (6) ◽  
pp. 1155-1164 ◽  
Author(s):  
Martha E. Plessas ◽  
Steven H. Strauss
Keyword(s):  
Gene Diversity ◽  
Random Mating ◽  
Natural Populations ◽  
Morphological Characters ◽  
Allele Frequencies ◽  
Monterey Pine ◽  
Fixation Indices ◽  
The One ◽  
Old Trees ◽  
Allozyme Loci

Four- to six-year-old trees were sampled from 9 to 10 stands in each of three natural populations of Monterey pine (Pinusradiata D. Don) and studied for genetic diversity at 37 allozyme loci. Among loci, Nei's gene diversity ranged from 73 to 100% within stands, 0 to 10% between stands within populations, and 0 to 27% between populations; average values were 94.9, 1.6, and 3.5%, respectively. F-statistic analyses (B. S. Weir and C. C. Cockerham. 1984. Evolution (Lawrence, Kans.), 38: 1358–1370) indicated higher levels of stand and population differentiation than did Nei's diversity statistics: 2.6 ± 0.7 and 6.2 ± 2.6%, respectively. Homozygotes were significantly in excess relative to expectations under random mating (FIS = 0.065). Most loci showed highly significant variation of allele frequencies among populations; Nei's genetic distance averaged 0.014. Genetic and geographic distances among stands were correlated only at Año Nuevo. Introgression of genes from knobcone pine (Pinusattenuata Lemm.) was evident in the one stand where the species were sympatric. Contrary to inferences from growth and morphological characters, allozyme frequencies and other biochemical characters suggest that the Año Nuevo population diverged prior to Cambria and Monterey. Differentiation among three cohorts was studied at 10 loci. Allele frequencies varied nonsignificantly between cohorts; mean fixation indices, however, decreased monotonically with cohort age, from 0.081 in embryos to 0.038 in 5-year-old trees to −0.119 in 14- to 17-year-old trees. Selection for the more outbred progeny was the outcome of stand development.

scholarly journals Application of temperature gradient gel electrophoresis to the characterization of a nitrifying bioaugmentation product

2003 ◽  
Vol 43 (2) ◽  
pp. 277-286 ◽  
Author(s):  
Melissa A. Fouratt ◽  
Jeremy S. Rhodes ◽  
Charles M. Smithers ◽  
Nancy G. Love ◽  
Ann M. Stevens
Keyword(s):  
Temperature Gradient ◽  
Gel Electrophoresis ◽  
Gradient Gel Electrophoresis ◽  
Temperature Gradient Gel Electrophoresis

scholarly journals Addressing widespread misidentifications of traditional medicinal mushrooms in Sanghuangporus (Basidiomycota) through ITS barcoding and designation of reference sequences

IMA Fungus ◽  
2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Shan Shen ◽  
Shi-Liang Liu ◽  
Ji-Hang Jiang ◽  
Li-Wei Zhou
Keyword(s):  
Species Identification ◽  
Rolling Circle Amplification ◽  
Practical Method ◽  
Morphological Characters ◽  
Its Sequences ◽  
Commercial Development ◽  
Medicinal Mushrooms ◽  
Rolling Circle ◽  
Reference Sequences ◽  
Its Barcoding

Abstract“Sanghuang” refers to a group of important traditionally-used medicinal mushrooms belonging to the genus Sanghuangporus. In practice, species of Sanghuangporus referred to in medicinal studies and industry are now differentiated mainly by a BLAST search of GenBank with the ITS barcoding region as a query. However, inappropriately labeled ITS sequences of “Sanghuang” in GenBank restrict accurate species identification and, to some extent, the utilization of these species as medicinal resources. We examined all available 271 ITS sequences related to “Sanghuang” in GenBank including 31 newly submitted sequences from this study. Of these sequences, more than half were mislabeled so we have now corrected the corresponding species names. The mislabeled sequences mainly came from strains utilized by non-taxonomists. Based on the analyses of ITS sequences submitted by taxonomists as well as morphological characters, we separate the newly described Sanghuangporus subbaumii from S. baumii and treat S. toxicodendri as a later synonym of S. quercicola. Fourteen species of Sanghuangporus are accepted, with intraspecific distances up to 1.30% (except in S. vaninii, S. weirianus and S. zonatus) and interspecific distances above 1.30% (except between S. alpinus and S. lonicerinus, and S. baumii and S. subbaumii). To stabilize the concept of these 14 species of Sanghuangporus, their taxonomic information and reliable ITS reference sequences are provided. Moreover, ten potential diagnostic sequences are provided for Hyperbranched Rolling Circle Amplification to rapidly confirm three common commercial species, viz. S. baumii, S. sanghuang, and S. vaninii. Our results provide a practical method for ITS barcoding-based species identification of Sanghuangporus and will promote medicinal studies and commercial development from taxonomically correct material.

scholarly journals Influence of Camembert consumption on the composition and metabolism of intestinal microbiota: a study in human microbiota-associated rats

2004 ◽  
Vol 92 (3) ◽  
pp. 429-438 ◽  
Author(s):  
Christophe Lay ◽  
Malène Sutren ◽  
Pascale Lepercq ◽  
Catherine Juste ◽  
Lionel Rigottier-Gois ◽  
...  
Keyword(s):  
Intestinal Microbiota ◽  
Dairy Products ◽  
Basal Diet ◽  
Fermented Milk ◽  
Metabolic Characteristics ◽  
Human Microbiota ◽  
Gradient Gel Electrophoresis ◽  
Metabolic Activities ◽  
Temperature Gradient Gel Electrophoresis ◽  
Micro Organisms

The objective of the present study was to evaluate the consequence of Camembert consumption on the composition and metabolism of human intestinal microbiota. Camembert cheese was compared with milk fermented by yoghurt starters andLactobacillus caseias a probiotic reference. The experimental model was the human microbiota-associated (HM) rat. HM rats were fed a basal diet (HMB group), a diet containing Camembert made from pasteurised milk (HMCp group) or a diet containing fermented milk (HMfm group). The level of micro-organisms from dairy products was measured in faeces using cultures on a specific medium and PCR–temporal temperature gradient gel electrophoresis. The metabolic characteristics of the caecal microbiota were also studied: SCFA, NH3, glycosidase and reductase activities, and bile acid degradations. The results showed that micro-organisms from cheese comprised 105–108bacteria/g faecal sample in the HMCp group.Lactobacillusspecies from fermented milk were detected in HMfm rats. Consumption of cheese and fermented milk led to similar changes in bacterial metabolism: a decrease in azoreductase activity and NH3concentration and an increase in mucolytic activities. However, specific changes were observed: in HMCp rats, the proportion of ursodeoxycholic resulting from chenodeoxycholic epimerisation was higher; in HMfm rats, α and β-galactosidases were higher than in other groups and both azoreductases and nitrate reductases were lower. The results show that, as for fermented milk, Camembert consumption did not greatly modify the microbiota profile or its major metabolic activities. Ingested micro-organisms were able to survive in part during intestinal transit. These dairy products exert a potentially beneficial influence on intestinal metabolism.

scholarly journals Morphological and Pathogenic Variability amongMacrophomina phaseolinaIsolates Associated with Mungbean (Vigna radiataL.) Wilczek from Pakistan

2014 ◽  
Vol 2014 ◽  
pp. 1-9 ◽  
Author(s):  
Umer Iqbal ◽  
Tariq Mukhtar
Keyword(s):  
Macrophomina Phaseolina ◽  
Morphological Characters ◽  
Geographic Origins ◽  
Low Weight ◽  
Breeding Programmes ◽  
Diverse Origin ◽  
Pathogenic Variability ◽  
Slow Growing ◽  
Highly Virulent ◽  
Medium Weight

Macrophomina phaseolinais a serious pathogen of many crops. In the present studies, 65 isolates ofMacrophomina phaseolinafrom different agroecological regions of Punjab and Khyber Pakhtunkhwa provinces of Pakistan were analyzed for morphological and pathogenic variability. Regardless of their geographic origins, significant differences were detected among 65 isolates in their radial growth, sclerotial size, and weight as well as in pathogenicity. Sixteen isolates were rated as fast growing, 11 as slow growing, and the rest of the isolates as medium growing. Nine isolates were classified as large sized, 26 as small sized, and the remaining 30 isolates as medium sized. Thirty five isolates were ranked as heavy weight, 12 as low weight, and the rest of isolates were grouped as medium weight. Ten fungal isolates appeared to be least virulent, whereas eight isolates of diverse origin proved to be highly virulent against mungbean cultivars. The remaining isolates were regarded as moderately virulent. No relationship was found among the morphological characters and pathogenicity of the isolates. These morphological and pathogenic variations in various isolates ofM. phaseolinamay be considered important in disease management systems and will be useful in breeding programmes of mungbean cultivars resistant to charcoal rot.

scholarly journals Nothing in (sponge) biology makes sense – except when based on holotypes

2015 ◽  
Vol 96 (2) ◽  
pp. 305-311 ◽  
Author(s):  
Dirk Erpenbeck ◽  
Merrick Ekins ◽  
Nicole Enghuber ◽  
John N.A. Hooper ◽  
Helmut Lehnert ◽  
...  
Keyword(s):  
New Species ◽  
Reference Material ◽  
Species Identification ◽  
Dna Sequences ◽  
Morphological Plasticity ◽  
Morphological Characters ◽  
Molecular Techniques ◽  
Reference Sequences ◽  
Species Descriptions ◽  
Preservation History

Sponge species are infamously difficult to identify for non-experts due to their high morphological plasticity and the paucity of informative morphological characters. The use of molecular techniques certainly helps with species identification, but unfortunately it requires prior reference sequences. Holotypes constitute the best reference material for species identification, however their usage in molecular systematics and taxonomy is scarce and frequently not even attempted, mostly due to their antiquity and preservation history. Here we provide case studies in which we demonstrate the importance of using holotype material to answer phylogenetic and taxonomic questions. We also demonstrate the possibility of sequencing DNA fragments out of century-old holotypes. Furthermore we propose the deposition of DNA sequences in conjunction with new species descriptions.

scholarly journals Pupae of the Nearctic species of Culicoides Latreille subgenus Monoculicoides Khalaf (Diptera: Ceratopogonidae)

Zootaxa ◽  
2018 ◽  
Vol 4504 (4) ◽  
pp. 451
Author(s):  
PHILLIP SHULTS ◽  
ART BORKENT
Keyword(s):  
Species Identification ◽  
Morphological Characters ◽  
Valid Species ◽  
Biogeographic Region ◽  
Nearctic Region

There are 160 valid species of Culicoides Latreille described from the Nearctic Region, but many are unknown as immatures or, although partially described, cannot be readily identified. We provide pupal diagnoses, descriptions, and a key to all seven known species of Culicoides subgenus Monoculicoides Khalaf occurring in the Nearctic biogeographic region. A diagnosis of several characters unique to this subgenus is provided to allow for the recognition of the included species from those of other subgeneric groupings. Microphotography of important morphological characters for both the key and descriptions are provided. This study highlights the usefulness of examining the pupae of Culicoides as a tool for species identification. The pupae of Culicoides grandensis Grogan & Phillips, C. occidentalis Wirth & Jones, and C. shemanchuki Grogan & Lysyk are newly described and those of C. riethi Kieffer, C. stigma (Meigen), and C. variipennis Wirth & Jones are redescribed in detail. The seventh species, C. sonorensis, was fully described recently. 

scholarly journals Denaturing gradient gel electrophoresis as a fingerprinting method for the analysis of soil microbial communities

2009 ◽  
Vol 55 (No. 10) ◽  
pp. 413-423 ◽  
Author(s):  
V. Valášková ◽  
P. Baldrian
Keyword(s):  
Microbial Communities ◽  
Gel Electrophoresis ◽  
Denaturing Gradient Gel Electrophoresis ◽  
Soil Microbial Communities ◽  
Soil Microbial ◽  
Genes Encoding ◽  
Gradient Gel Electrophoresis ◽  
Temperature Gradient Gel Electrophoresis ◽  
Experimental Treatments ◽  
Multiple Samples

In soil microbial ecology, the effects of environmental factors and their gradients, temporal changes or the response to specific experimental treatments of microbial communities can only be effectively analyzed using methods that address the structural differences among whole communities. Fingerprinting methods are the most appropriate technique for this task when multiple samples must be analyzed. Among the methods currently used to compare microbial communities based on nucleic acid sequences, the techniques based on differences in the melting properties of double-stranded molecules, denaturing gradient gel electrophoresis (DGGE) or temperature gradient gel electrophoresis (TGGE), are the most widely used. Their main advantage is that they provide the possibility to further analyze whole sequences contained in fingerprints using molecular methods. In addition to the analysis of microbial communities based on DNA extracted from soils, DGGE/TGGE can also be used for the assessment of the active part of the community based on the analysis of RNA-derived sequences or for the analysis of sequences of functional genes encoding for proteins involved in important soil processes.

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