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1.
Nine species of Scaphidiinae are newly reported for New Brunswick, Canada, bringing the total number of species known from the province to 12. Scaphium castanipes Kirby, Baeocera inexspectata Löbl and Stephen, Baeocera securiforma (Cornell), Scaphisoma repandum Casey, and Toxidium gammaroides LeConte are reported for the first time from the Maritime provinces. Siagonum punctatum LeConte and Siagonum stacesmithi Hatch, and the subfamily Piestinae are reported for the first time from New Brunswick. The subfamily Osoriinae is reported for the first time from New Brunswick and the Maritime provinces based on the collection of three species: Clavilispinus prolixus (LeConte), Thoracophorus costalis (Erichson), and a Lispinodes species. The Lispinodes species is also newly recorded for Canada. Six species of Oxytelinae are newly recorded from New Brunswick, bringing the total number of species of this subfamily known to the province to 20. Apocellus sphaericollis (Say) and Platystethus americanus Erichson are new to the Maritime provinces. Additional locality and bionomic data are presented for Mitosynum vockerothi Campbell, and the male genitalia are illustrated for the first time. Collection and bionomic data are presented for all included species. 相似文献
2.
Using Escherichia coli for installing and maintaining anaerobiosis for hydrogen production by Clostridium acetobutylicum ATCC 824 is a cost-effective approach for industrial hydrogen production, as it does not require reducing agents or sparging with inert gases. This study was devoted for investigating the feasibility for installing and maintaining anaerobiosis of hydrogen production by C. acetobutylicum ATCC 824 when using E. coli HD701 utilizable versus non utilizable sugars as a-carbon source. Using E. coli HD701 for installing anaerobiosis showed a comparable hydrogen production yield and efficiency to the use of reducing agents and nitrogen sparging in case of hydrogen production from the E. coli HD701 non utilizable sugars. In contrast, using E. coli HD701 for installing anaerobiosis showed a lower hydrogen production yield and efficiency than the use of reducing agents and nitrogen sparging in case of using glucose as a substrate. This is possibly because E. coli HD701 when using glucose compensate for the substrate, and produce hydrogen with lower efficiency than C. acetobutylicum ATCC 824. These results indicated that the use of E. coli HD701 for installing anaerobiosis would not be economically feasible when using E. coli HD701 utilizable sugars as a carbon source. In contrast, the use of this approach for installing anaerobiosis for hydrogen production from sucrose and starch would have a high potency for industrial applications. 相似文献
3.
Jairo Alfonso Mendoza-Roldan Andrea Zatelli Maria Stefania Latrofa Roberta Iatta Marcos Antonio Bezerra-Santos Giada Annoscia Floriana Gernone Jan Votýpka David Modrý Lucie Tich Petr Volf Domenico Otranto 《PLoS neglected tropical diseases》2022,16(8)
The trypanosomatid protist Leishmania tarentolae is a saurian-associated parasite vectored by the Sergentomyia minuta sand fly. This study aimed to confirm the circulation of L. infantum and L. tarentolae in sand flies, reptiles and dogs and to isolate new strains of these protists. Reptilian and sheltered dog blood samples were collected, and sand flies were captured. Samples were tested for Leishmania spp. using duplex real-time PCR (dqPCR) and real-time PCR (qPCR); the origin of blood meal was identified in engorged sand flies by conventional PCR. The reptilian blood and intestinal content of sand fly females were cultured. Dog sera were tested by IFAT using both Leishmania species. Four Tarentola mauritanica geckoes were molecularly positive for L. infantum or L. tarentolae, with no co-infections; moreover, amastigote-like forms of L. infantum were observed in the bone marrow. 24/294 sand flies scored positive for Leishmania spp. by dqPCR, 21 S. minuta and two Phlebotomus perniciosus were positive for L. tarentolae, while only a single Ph. perniciosus was positive for L. infantum. Blood meal analysis confirmed reptile and dog in S. minuta, dog and human in Ph. perniciosus and dog in Phlebotomus neglectus. Two axenic strains of L. tarentolae were obtained. Twelve of 19 dogs scored positive for L. infantum and L. tarentolae by IFAT and three of them also for L. infantum by dqPCR, and six by qPCR. These data confirm the sympatric circulation of L. infantum and L. tarentolae in geckoes, sand flies, and dogs, and suggest that geckoes may be infected with L. infantum. 相似文献
4.
The Waxy Locus in Maize III. Effect of Structural Heterozygosity on Intragenic Recombination and Flanking Marker Assortment 总被引:1,自引:0,他引:1
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Nelson OE 《Genetics》1975,79(1):31-44
The effect of heterozygosity for structural rearrangements on recombination between two wx heteroalleles (C and 90) and the pattern of flanking markers in the resultant Wx gametes has been examined. The rearrangements are Tp9, an insertional translocation in which a segment of chromosome 3 has been inserted into the short arm of chromosome 9 close to the wx locus; In9a, a long pericentric inversion with wx in the inverted segment; and Rearr 9, a complex rearrangement of chromosome 9. Heterozygosity for rearrangements decreases the frequency of Wx gametes to varying degrees.—Heterozygosity for Tp9 enhances the proportion of Wx gametes that are apparent convertants and allows the conclusion that such gametes do not normally arise from an exchange in the wx locus plus a second exchange distal to wx. Heterozygosity for In9a markedly decreases the frequency of Wx gametes that are recombinant for outside markers but does not decrease the frequency of convertants.—Heterozygosity for Rearr 9 permits a low frequency of Wx gametes, all of which are apparent convertants.—A high proportion of the convertants have the flanking markers that entered the cross with C so recombination is polarized in normal homologs and in heterozygotes for all rearrangements. 相似文献
5.
New replacement names are proposed for seven species of the subfamily Typhlocybinae; one new synonym is recognized in the family Delphacidae. The following changes are proposed: Empoasca (Empoasca) angustata
nom.nov. for Empoasca angusta Linnavuori & DeLong (not Dworakowska); Empoasca (Empoasca) chilensis
nom.nov. for Empoasca diversa Linnavuori & DeLong (not Vilbaste); Austroasca verdensis
nom.nov. for Empoasca artemisiae Lindberg (not Lethierry); Kropka vidanoi Dworakowska for Erythroneura unipunctata Dlabola (not Cerutti); Zyginella vietnamica
nom. nov. for Zyginella melichari Dworakowska (not Kirkaldy); Eupteryx (Eupteryx) dlabolai
nom. nov. for Eupteryx octonotata Dlabola (not Hardy); Baaora ahmedi
nom. nov. for Baaora spinosa (Ahmed) (not Beamer); Paradelphacodes insolitus Dmitriev is synonymized with Paradelphacodes gvosdevi (Mitjaev), syn. nov. 相似文献
6.
Anne I. Gondim Carmen Alonso Thelma L. P. Dias Cynthia L. C. Manso Martin L. Christoffersen 《ZooKeys》2013,(307):45-96
We provide the first annotated checklist of ophiuroids from the continental shelf of the State of Paraíba, northeastern Brazil. Identification keys and taxonomic diagnoses for 23 species, belonging to 14 genera and 8 families, are provided. The material is deposited in the Invertebrate Collection Paulo Young, at the Federal University of Paraíba. Ophiopsila hartmeyeri represents the first record for the northeastern region of Brazil, while Ophiolepis impressa, Ophiolepis paucispina, Amphiura stimpsoni, Amphiodia riisei, Ophiactis quinqueradia, Ophiocoma wendtii and Ophionereis olivaceae are new records for the State of Paraíba. The number of species known for the state was increased from 16 to 23, representing approximately 17% of the species known for Brazil and 54% of the species known for northeastern Brazil. The recorded fauna has a large geographical and bathymetrical distribution. 相似文献
7.
Ismael Sánchez-Jiménez Jaume Pellicer Oriane Hidalgo Sònia Garcia Teresa Garnatje Joan Vallès 《Folia Geobotanica》2009,44(3):307-322
Chromosome counts are reported for 15 species of the family Asteraceae from Inner Mongolia (People’s Republic of China). This study includes representatives of the tribes Anthemideae (Artemisia, Chrysanthemum, Filifolium, Hippolytia and Neopallasia), Astereae (Heteropappus) and Cardueae (Echinops and Olgaea). The significance of the chromosome counts is discussed for each species. Within the Anthemideae, chromosome counts for Hippolytia alashanensis (2n?=?36) and the tetraploid level of Artemisia eriopoda (2n?=?36) are reported for the first time. The chromosome number of Heteropappus altaicus (Astereae) agrees with previous reports of one (4x) of the two ploidy levels reported for this taxon. As a complement to the karyological data, genome size of the Cardueae representatives was assessed using flow cytometry. Within this tribe, Echinops gmelini (2n?=?26) and its sister taxon E. acantholepis (2n?=?14) show strongly divergent karyological patterns of difficult interpretation, whereas the count of E. przewalskyi (2n?=?32), assigned here for the first time, coincides with those of its close relatives. In Olgaea tangutica, the chromosome count (2n?=?24) and genome size (2C?=?3.01 pg) given here are the first reports for both the species and the genus. 相似文献
8.
In light of a number of recent studies highlighting the increasing research interest in bruchids, it is crucial to validate suitable reference genes that could be used in quantitative gene expression studies. Callosobruchus maculatus is a serious pest of stored grains and field legumes in which reference genes have not been assessed and validated to date. The present study aimed to identify and validate reference genes in different developmental stages of C. maculatus shortlisted from commonly used reference genes such as VATPase, TRIP12, TBP, TF11D, ACTIN, GST, ANNEXIN, PTCD3, RPL32, and β -Tub in various insects. Dedicated algorithms like GeNorm, NormFinder, and BestKeeper were used to analyze the stability of these candidate genes, which revealed GST for third instar, ANNEXIN and PTCD3 for the fourth instar, TF11D and VATPase for male pupa, RPL32 and β-tub for female pupa, β-tub and TBP for adult male and VATPase and GST for adult females as suitable reference genes for expression studies in C. maculatus. The final comprehensive ranking using RefFinder identified GST and TBP as the best reference genes for all the developmental stages of C. maculatus. To the best of our knowledge, this is the first report which evaluates and validates stable reference genes in C. maculatus. The information of stage-specific gene expression, generated in this study will be useful for future molecular, physiological, and biochemical studies on C. maculatus and other closely related bruchids. 相似文献
9.
10.
Characterization of the Role of para-Aminobenzoic Acid Biosynthesis in Folate Production by Lactococcus lactis
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Arno Wegkamp Wietske van Oorschot Willem M. de Vos Eddy J. Smid 《Applied microbiology》2007,73(8):2673-2681
The pab genes for para-aminobenzoic acid (pABA) biosynthesis in Lactococcus lactis were identified and characterized. In L. lactis NZ9000, only two of the three genes needed for pABA production were initially found. No gene coding for 4-amino-4-deoxychorismate lyase (pabC) was initially annotated, but detailed analysis revealed that pabC was fused with the 3′ end of the gene coding for chorismate synthetase component II (pabB). Therefore, we hypothesize that all three enzyme activities needed for pABA production are present in L. lactis, allowing for the production of pABA. Indeed, the overexpression of the pABA gene cluster in L. lactis resulted in elevated pABA pools, demonstrating that the genes are involved in the biosynthesis of pABA. Moreover, a pABA knockout (KO) strain lacking pabA and pabBC was constructed and shown to be unable to produce folate when cultivated in the absence of pABA. This KO strain was unable to grow in chemically defined medium lacking glycine, serine, nucleobases/nucleosides, and pABA. The addition of the purine guanine, adenine, xanthine, or inosine restored growth but not the production of folate. This suggests that, in the presence of purines, folate is not essential for the growth of L. lactis. It also shows that folate is not strictly required for the pyrimidine biosynthesis pathway. L. lactis strain NZ7024, overexpressing both the folate and pABA gene clusters, was found to produce 2.7 mg of folate/liter per optical density unit at 600 nm when the strain was grown on chemically defined medium without pABA. This is in sharp contrast to L. lactis strains overexpressing only one of the two gene clusters. Therefore, we conclude that elevated folate levels can be obtained only by the overexpression of folate combined with the overexpression of the pABA biosynthesis gene cluster, suggesting the need for a balanced carbon flux through the folate and pABA biosynthesis pathway in the wild-type strain. 相似文献
11.
12.
《Journal of Asia》2022,25(1):101846
Meloidogyne incognita is one of the most important plant parasitic nematodes. This study was conducted to determine the nematicidal potential of Beauveria bassiana and Metarhizium anisopliae against M. incognita. B. bassiana and M. anisopliae spore suspensions and bio -nematicide, Purpureocillium lilacinum were applied. B. bassiana and M. anisopliae revealed considerable nematicidal activity against M. incognita in tomato and cucumber. The gall index decreased gradually from 8.0 for control to 3.2, 2.0 and 2.2 for B. bassiana, M. anisopliae and P. lilacinum in tomato, respectively. The highest reduction (%) in gall formation (control index) was calculated as 75.2 % in M. anisopliae treated group for tomato. The gall index was 7.6 for control, but decreased to 3.6, 2.0 and 2.2 for B. bassiana, M. anisopliae and P. lilacinum in cucumber, respectively. The highest control index was 71.7 % for M. anisopliae in cucumber. The number of the second instar juveniles of M. incognita was recorded as 2240 for control. However, this value reduced to 508, 332 and 328 by B. bassiana, M. anisopliae and P. lilacinum in tomato, respectively. The highest control indexes for the second instar juveniles were 85.2 % and 85.3 % for M. anisopliae and P. lilacinum in tomato, respectively. Alike, the highest control indexes were 84.9 % and 85.7 % for the same applications in cucumber, respectively. B. bassiana and M. anisopliae displayed also positive effect on the number of leaves, dry and fresh root weights of tomato. The results showed that B. bassiana and M. anisopliae can be considered as an alternative. 相似文献
13.
Shuffling of Promoters for Multiple Genes To Optimize Xylose Fermentation in an Engineered Saccharomyces cerevisiae Strain
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We describe here a useful metabolic engineering tool, multiple-gene-promoter shuffling (MGPS), to optimize expression levels for multiple genes. This method approaches an optimized gene overexpression level by fusing promoters of various strengths to genes of interest for a particular pathway. Selection of these promoters is based on the expression levels of the native genes under the same physiological conditions intended for the application. MGPS was implemented in a yeast xylose fermentation mixture by shuffling the promoters for GND2 and HXK2 with the genes for transaldolase (TAL1), transketolase (TKL1), and pyruvate kinase (PYK1) in the Saccharomyces cerevisiae strain FPL-YSX3. This host strain has integrated xylose-metabolizing genes, including xylose reductase, xylitol dehydrogenase, and xylulose kinase. The optimal expression levels for TAL1, TKL1, and PYK1 were identified by analysis of volumetric ethanol production by transformed cells. We found the optimal combination for ethanol production to be GND2-TAL1-HXK2-TKL1-HXK2-PYK1. The MGPS method could easily be adapted for other eukaryotic and prokaryotic organisms to optimize expression of genes for industrial fermentation. 相似文献
14.
Mohamed Hamada Ayman Elbehiry Eman Marzouk Ihab M. Moussa Ashgan Mohamed Hessain Jwaher Haji Alhaji Hassan A. Heme Rasha Zahran Eman Abdeen 《Saudi Journal of Biological Sciences》2018,25(6):1072-1078
Although Helicobacter pylori (H. pylori) is a highly significant pathogen, its source remains unclear. Many people consume chicken daily as a source of animal protein worldwide; thus, hygienic methods of supplying chickens for consumption are critical for public health. Therefore, our study examined the distribution of the glmM (ureC), babA2, vacA and cagA virulence genes in H. pylori strains in chicken meat and giblets (gizzards and livers) and the resistance of the strains to various antibiotics. Ninety chicken meat, gizzard and liver samples were obtained from a semi-automatic abattoir in Sadat City, Egypt, and were cultured and preliminarily analyzed using biochemical tests. The presence of the ureC, babA2, vacA and cagA genotypes was tested for in samples positive for H. pylori by multiplex polymerase chain reaction (Multiplex-PCR). The resistance of H. pylori to various antimicrobial drugs was tested using the disc diffusion method. In total, 7 of the 90 chicken samples were positive for H. pylori (7.78%); in 3/7 (42.85%) samples, the bacteria were found in the chicken liver, while the bacteria were found in the meat in 2/7 (28.57%) and in the gizzard in 2/7 (28.57%) samples. The total prevalence of both the ureC and babA2 genes in the isolated H. pylori strains was 100%, while the prevalence of the vacA and cagA genes was 57.1% and 42.9%, respectively. The resistance of H. pylori to the antibiotics utilized in our study was 100% for streptomycin; 85.7% for amoxicillin and penicillin; 71.4% for oxytetracycline, nalidixic acid and ampicillin; 57.1% for sulfamethoxazole and erythromycin; and 42.9% for neomycin, chloramphenicol and norfloxacin. In conclusion, the chicken meat and giblets were tainted by H. pylori, with a higher occurrence of the ureC, babA2, vacA and cagA genotypes. Future investigations should investigate the resistance of H. pylori to various antimicrobial agents in Egypt. 相似文献
15.
Identification and testing of reference genes for Sesame gene expression analysis by quantitative real-time PCR 总被引:1,自引:0,他引:1
Sesame (Sesamum indicum L.) is an ancient and important oilseed crop. However, few sesame reference genes have been selected for quantitative real-time PCR until now. Screening and validating reference genes is a requisite for gene expression normalization in sesame functional genomics research. In this study, ten candidate reference genes, i.e., SiACT, SiUBQ6, SiTUB, Si18S rRNA, SiEF1α, SiCYP, SiHistone, SiDNAJ, SiAPT and SiGAPDH, were chosen and examined systematically in 32 sesame samples. Three qRT-PCR analysis methods, i.e., geNorm, NormFinder and BestKeeper, were evaluated systematically. Results indicated that all ten candidate reference genes could be used as reference genes in sesame. SiUBQ6 and SiAPT were the optimal reference genes for sesame plant development; SiTUB was suitable for sesame vegetative tissue development, SiDNAJ for pathogen treatment, SiHistone for abiotic stress, SiUBQ6 for bud development and SiACT for seed germination. As for hormone treatment and seed development, SiHistone, SiCYP, SiDNAJ or SiUBQ6, as well as SiACT, SiDNAJ, SiTUB or SiAPT, could be used as reference gene, respectively. To illustrate the suitability of these reference genes, we analyzed the expression variation of three functional sesame genes of SiSS, SiLEA and SiGH in different organs using the optimal qRT-PCR system for the first time. The stability levels of optimal and worst reference genes screened for seed development, anther sterility and plant development were validated in the qRT-PCR normalization. Our results provided a reference gene application guideline for sesame gene expression characterization using qRT-PCR system. 相似文献
16.
Duncan N. Ndegwa Prasun Kundu Jessica B. Hostetler Alejandro Marin-Menendez Theo Sanderson Kioko Mwikali Lisa H. Verzier Rachael Coyle Sophie Adjalley Julian C. Rayner 《PLoS pathogens》2021,17(7)
Plasmodium vivax is responsible for the majority of malaria cases outside Africa. Unlike P. falciparum, the P. vivax life-cycle includes a dormant liver stage, the hypnozoite, which can cause infection in the absence of mosquito transmission. An effective vaccine against P. vivax blood stages would limit symptoms and pathology from such recurrent infections, and therefore could play a critical role in the control of this species. Vaccine development in P. vivax, however, lags considerably behind P. falciparum, which has many identified targets with several having transitioned to Phase II testing. By contrast only one P. vivax blood-stage vaccine candidate based on the Duffy Binding Protein (PvDBP), has reached Phase Ia, in large part because the lack of a continuous in vitro culture system for P. vivax limits systematic screening of new candidates. We used the close phylogenetic relationship between P. vivax and P. knowlesi, for which an in vitro culture system in human erythrocytes exists, to test the scalability of systematic reverse vaccinology to identify and prioritise P. vivax blood-stage targets. A panel of P. vivax proteins predicted to function in erythrocyte invasion were expressed as full-length recombinant ectodomains in a mammalian expression system. Eight of these antigens were used to generate polyclonal antibodies, which were screened for their ability to recognize orthologous proteins in P. knowlesi. These antibodies were then tested for inhibition of growth and invasion of both wild type P. knowlesi and chimeric P. knowlesi lines modified using CRISPR/Cas9 to exchange P. knowlesi genes with their P. vivax orthologues. Candidates that induced antibodies that inhibited invasion to a similar level as PvDBP were identified, confirming the utility of P. knowlesi as a model for P. vivax vaccine development and prioritizing antigens for further follow up. 相似文献
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18.
Pedro E. Fleitas Noelia Floridia-Yapur Elvia E. Nieves Adriana Echazu Paola A. Vargas Nicols R. Caro Ramiro Aveldao Walter Lopez Mariana Fernandez Favio Crudo Rubn O. Cimino Alejandro J. Krolewiecki 《PLoS neglected tropical diseases》2022,16(2)
BackgroundStrongyloidiasis and Chagas disease are endemic in northern Argentina. In this study we evaluate the association between S. stercoralis and T. cruzi infections in villages with diverse prevalence levels for these parasites. Further understanding in the relationship between these Neglected Tropical Diseases of South America is relevant for the design of integrated control measures as well as exploring potential biologic interactions.MethodologyCommunity based cross-sectional studies were carried in different villages of the Chaco and Yungas regions in Argentina. Individuals were diagnosed by serology for S. stercoralis and T. cruzi. The association between S. stercoralis and T. cruzi, and between anemia and the two parasites was evaluated using two approaches: marginal (Ma) and multilevel regression (Mu).ResultsA total of 706 individuals from six villages of northern Argentina were included. A total of 37% were positive for S. stercoralis, 14% were positive for T. cruzi and 5% were positive for both. No association was found between infection with S. stercoralis and T. cruzi in any of the models, but we found a negative correlation between the prevalence of these species in the different villages (r = -0.91). Adults (> 15 years) presented association with S. stercoralis (Ma OR = 2.72; Mu OR = 2.84) and T. cruzi (Ma OR = 5.12; Mu OR = 5.48). Also, 12% and 2% of the variance of infection with S. stercoralis and T. cruzi, respectively, could be explained by differences among villages. On the other hand, anemia was associated with infection with S. stercoralis (Ma OR = 1.73; Mu OR = 1.78) and was more prevalent in adults (Ma OR = 2.59; Mu OR = 2.69).ConclusionWe found that coinfection between S. stercoralis and T. cruzi is not more frequent than chance in endemic areas. However, the high prevalence for both parasites, raises the need for an integrated strategy for the control of STH and Chagas disease. 相似文献
19.
Occurrence of Genes Associated with Enterotoxigenic and Enterohemorrhagic Escherichia coli in Agricultural Waste Lagoons 总被引:1,自引:0,他引:1
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The prevalence among all Escherichia coli bacteria of the LTIIa toxin gene and STII toxin gene, both associated with enterotoxigenic E. coli, and of three genes (stxI, stxII, and eaeA) associated with enterohemorrhagic E. coli was determined in farm waste disposal systems seasonally for 1 year. Single- and nested-PCR results for the number of E. coli isolates carrying each toxin gene trait were compared with a five-replicate most-probable-number (MPN) method. The STII and LTIIa toxin genes were present continuously at all farms and downstream waters that were tested. Nested-MPN-PCR manifested sensitivity increased over that of single-MPN-PCR by a factor of 32 for LTIIa, 10 for STII, and 2 for the stxI, stxII, and eaeA genes. The geometric mean prevalence of each toxin gene within the E. coli community in waste disposal site waters after nested MPN-PCR was 1:8.5 E. coli isolates (1:8.5 E. coli) for the LTIIa toxin gene and 1:4 E. coli for the STII toxin gene. The geometric mean prevalence for the simultaneous occurrence of toxin genes stxI, stxII, and eaeA, was 1:182 E. coli. These findings based on total population analysis suggest that prevalence rates for these genes are higher than previously reported in studies based on surveys of single isolates. With a population-based approach, the frequency of each toxin gene at the corresponding disposal sites and the endemic nature of diseases on farms can be easily assessed, allowing farmers and public health officials to evaluate the risk of infection to animals or humans. 相似文献
20.
Ismael Sánchez-Jiménez Oriane Hidalgo Miguel ángel Canela Sonja Siljak-Yakovlev Marija Edita ?oli? Joan Vallès Teresa Garnatje 《Plant Systematics and Evolution》2012,298(6):1085-1099
This work focuses on the representatives of genus Echinops (Asteraceae, Cardueae) in the Aegean and Balkan regions, from the perspective of their genome evolution. Chromosome numbers were determined by orcein staining in 14 populations of nine taxa, and DNA contents were assessed by flow cytometry in 24 populations of nine taxa. A molecular phylogeny based on the internal transcribed spacer (ITS) and trnL-trnF and including first sequences for two taxa (Echinops sphaerocephalus subsp. taygeteus and E.?spinosissimus subsp. neumayeri) provided a framework for discussing genome changes. From a methodological point of view, similar C-DNA value estimates were obtained when measuring, for a same population, fresh leaves from adult plants collected in the field and from cultivated seedlings. Conversely, despite giving the appearance of being correct (e.g., low coefficient of variation), genome size assessed using silica gel-preserved material differs significantly from values obtained for the same populations with fresh material. Nevertheless, silica gel-preserved material may still provide rough estimates of genome size for, e.g., inferring ploidy level. Suitable—non-silica gel-based—DNA amounts assessed for 23 populations range from 2C?=?6.52?pg (E.?spinosissimus subsp. neumayeri) to 2C?=?9.37?pg (E.?bannaticus). Chromosome counts were established for the first time for Echinops graecus (2n?=?32), E.?sphaerocephalus subsp. albidus (2n?=?32), E.?sphaerocephalus subsp. taygeteus (2n?=?ca.?30), and E.?spinosissimus subsp. neumayeri (2n?=?28). Genome size and chromosome number are confirmed as crucial parameters for deciphering lineage diversification within the genus Echinops. 相似文献