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LUCIANO BULLINI ROSSELLA CIANCHI PAOLA ARDUINO LINO DE BONIS MARIA CRISTINA MOSCO REA VERARDI DANIELE PORRETTA BRUNO CORRIAS WALTER ROSSI 《Biological journal of the Linnean Society. Linnean Society of London》2001,72(2):193-201
The hybrid origin of the western Mediterranean orchid Dactylorhiza insularis was demonstrated by genetic markers. Allozyme data showed that throughout its range D. insularis has an allotriploid constitution and reproduces apomictically. The parental species of D. insularis were identified as D. romana andD. sambucina; they contributed 2 alleles and 1 allele, respectively, at the allozyme loci studied. The maternal species of D. insularis was D. romana , as inferred from cpDNA ( trn L(UAA) intron). High genetic similarities were found when comparing present populations of D. romana and D. sambucina with their respective genomes 'frozen' in D. insularis. Dactylorhiza insularis showed fixed (or nearly fixed) heterozygosity at 11 out of the 19 loci studied, and poor genetic variation: eight multilocus genotypes were detected at allozyme level. No multilocus genotype differs from the most similar one by more than one allele substitution. All D. insularis individuals showed the same cpDNA haplotype (I) , regardless of their geographic origin and multilocus genotype. The I haplotype is similar, but not identical to that found in D. romana (R). No recurrent formation of D. insularis was observed in hybrid zones between D. romana and D. sambucina , where diploid sexual hybrids (F1; Fn , backcrosses) were detected. Available data agree with a single origin for D. insularis , which possibly occurred in the present postglacial, when D. romana and D. sambucina , expanding from their glacial refugia, came into contact. The genetic homogeneity found between D. romana and D. markusii , both from their locus classicus , indicates that the latter is a junior synonym of D. romana; on the other hand, D. romana and D. sambucina are well differentiated species ( DNei = 0.59). 相似文献
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ABSTRACT. 1. The gall-midge Asphondylia boerhaaviae Möhn galls weeds belonging to the Nyctaginaceae in Jamaica and other parts of the Caribbean. The species breeds throughout the year with a generation length of < 1 month.
2. In adult females, plots of wing length on hind tibial length, of maximum potential fecundity (m.p.f.) on wing length, and of m.p.f. on ovariole number, suggested the presence of a small morph, which the use of discriminant function analysis and other investigations confirmed. There was also good evidence of two size morphs in adult males.
3. Both body size and ovariole number had significant effects on m.p.f. but these effects were different in the two morphs. While the food plants had significant influences on size and fecundity, these were relatively small. The m.p.f. of the small morph was 125.8±11.1 eggs, and of the large morph 318.7±8.3 (95% cl).
4. Laboratory experiments on the flight performance of newly-emerged midges indicated that the small morph was not dispersive and that about 80% of the large morph was dispersive. No differences in size, wing length or fecundity could be found between the two behavioural types of the large morph.
5. The nature of the polymorphism is unusual, particularly since the dispersive individuals potentially have similar (or greater) fecundity than the non-dispersive ones.
6. Estimates of achieved fecundity (eggs actually laid, rather than m.p.f.) were 67.8±9.6 (field, minimum) and 138.9±30.4 (laboratory), the latter estimate being based on large-morph females. 相似文献
2. In adult females, plots of wing length on hind tibial length, of maximum potential fecundity (m.p.f.) on wing length, and of m.p.f. on ovariole number, suggested the presence of a small morph, which the use of discriminant function analysis and other investigations confirmed. There was also good evidence of two size morphs in adult males.
3. Both body size and ovariole number had significant effects on m.p.f. but these effects were different in the two morphs. While the food plants had significant influences on size and fecundity, these were relatively small. The m.p.f. of the small morph was 125.8±11.1 eggs, and of the large morph 318.7±8.3 (95% cl).
4. Laboratory experiments on the flight performance of newly-emerged midges indicated that the small morph was not dispersive and that about 80% of the large morph was dispersive. No differences in size, wing length or fecundity could be found between the two behavioural types of the large morph.
5. The nature of the polymorphism is unusual, particularly since the dispersive individuals potentially have similar (or greater) fecundity than the non-dispersive ones.
6. Estimates of achieved fecundity (eggs actually laid, rather than m.p.f.) were 67.8±9.6 (field, minimum) and 138.9±30.4 (laboratory), the latter estimate being based on large-morph females. 相似文献
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Surveillance of biting midges (Culicoides spp.) in Northern Ireland: influence of seasonality,surrounding habitat and livestock housing
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S. JESS G. M. THOMPSON S. CLAWSON I. W. N. FORSYTHE I. REA A. W. GORDON A. K. MURCHIE 《Medical and veterinary entomology》2018,32(1):48-60
Biting midges, Culicoides spp. (Diptera: Ceratopogonidae), are important vectors of viral pathogens. Following the outbreak of bluetongue serotype 8 in Europe between 2006 and 2009, many Culicoides surveillance programmes were initiated to identify vector‐active periods, in accordance with European Commission regulation 2007/1266/EC. This study utilized surveillance data from 4 years of continuous light‐trapping at 14 sites in Northern Ireland. The number of captured Culicoides varied from none during the vector‐free period (December–April) to more than 36 000 per night during peak activity in the summer. The Obsoletus group represented 75% of Culicoides collected and the Pulicaris group represented 21%. A total of 91% of Culicoides were female, of which 42% were parous. Abundance data, sex ratios and parous rates suggested that both the Obsoletus and Pulicaris groups underwent three generations/year. The Obsoletus group was associated with cattle‐rearing habitats and woodland, the Impunctatus group was found in habitats related to sheep rearing and the Pulicaris group were associated with both cattle and sheep. Housing did not reduce incursion of female Obsoletus group Culicoides but it did for males and for the Pulicaris group Culicoides. The influence of housing was strongly affected by time of year, probably reflecting the presence of livestock indoors/outdoors. 相似文献
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MARCOS A. VANNIER-SANTOS JULIO A. URBINA REA MARTINY REA NEVES WANDERLEY DE SOUZA 《The Journal of eukaryotic microbiology》1995,42(4):337-346
ABSTRACT. The antiproliferative effects and ultrastructural alterations induced in vitro by two antifungal compounds, the azole ketoconazole and the allylamine terbinafine on Leishmania amazonensis are reported. Promastigotes treatment with ketoconazole and terbinafine induced growth arrest and cell lysis in 72 hours. Combination of the two agents produced additive effects on promastigote axenic growth and synergistic effects on intracellular amastigote proliferation. The amastigotes, either axenically grown or infecting murine macrophages, were about 100-fold more sensitive to the drugs. These compounds induced the appearance of large multivesicular bodies, especially after ketoconazole treatment, increased amount of lipid inclusions as well as numerous, polymorphic volutin granules, particularly in terbinafine-treated cells. Multivesicular bodies were observed in close apposition with organelles such as mitochondria, which also showed alterations in the distribution and appearance of cristae, and the formation of paracrystalline arrays within the matrix. Some cells presented large portions of cytoplasm wrapped by endoplasmic reticulum and many parasites also presented myelin-like endoplasmic reticulum profiles. Such alterations together with the strong acid phosphatase activity observed in the multivesicular bodies and volutin granules may indicate the existence of an unusual autophagic process in cells treated with ergosterol biosynthesis inhibitors. 相似文献