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41.
Four ‘doubtful species’ are listed in catalogues of the genus Heliconius. All are non–existent: (1) H. Carolina (Herbst) is a forgery made from trimmed fragments of at least three butterflies, the two identifiable ones both beingH. erato; (2) H.cinereo–fuscus (Goeze) is a faded specimen of H.ricini; (3) H.arcuatus (Goeze) is so inadequately described that its identity cannot be determined, although it is apparently some species of heliconiine or ithomiine;(4)H.euclea (Godart) is the valid senior name of an ithomiid in the genus Hypothyris. 相似文献
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43.
RUTH M. BROWN RICHARD A. NICHOLS CHRIS G. FAULKES CARL G. JONES LEANDRO BUGONI VIKASH TATAYAH DADA GOTTELLI WILLIAM C. JORDAN 《Molecular ecology》2010,19(15):3157-3170
Historical records suggest that the petrels of Round Island (near Mauritius, Indian Ocean) represent a recent, long‐distance colonization by species originating from the Atlantic and Pacific Oceans. The majority of petrels on Round Island appear most similar to Pterodroma arminjoniana, a species whose only other breeding locality is Trindade Island in the South Atlantic. Using nine microsatellite loci, patterns of genetic differentiation in petrels from Round and Trindade Islands were analysed. The two populations exhibit low but significant levels of differentiation in allele frequencies and estimates of migration rate between islands using genetic data are also low, supporting the hypothesis that these populations have recently separated but are now isolated from one another. A second population of petrels, most similar in appearance to the Pacific species P. neglecta, is also present on Round Island and observations suggest that the two petrel species are hybridizing. Vocalizations recorded on the island also suggest that hybrid birds may be present within the population. Data from microsatellite genotypes support this hypothesis and indicate that there may have been many generations of hybridization and back‐crossing between P. arminjoniana and P. neglecta on Round Island. Our results provide an insight into the processes of dispersal and the consequences of secondary contact in Procellariiformes. 相似文献
44.
ROBIN A. MARRS RUTH A. HUFBAUER STEVEN M. BOGDANOWICZ REN SFORZA 《Molecular ecology resources》2006,6(3):897-899
Centaurea stoebe (subspecies C. s. stoebe and C. s. micranthos[S. G. Gmelin ex Gugler) Hayek] and Centaurea diffusa are Eurasian plant species that have invaded much of North America. We isolated seven microsatellite loci from C. stoebe and two loci from C. diffusa. All loci described here amplify in both species and have between six and 25 alleles each. These markers will be useful in examining population structure and addressing questions regarding these invasions. 相似文献
45.
RUTH M. HAMILL MOHAMED A. F. NOOR ERIC T. WATSON MICHAEL G. RITCHIE 《Molecular ecology resources》2006,6(2):340-342
Ephippiger ephippiger is a model organism for studies of sexual selection and phylogeography but little is known about fine‐scale population structure. Available microsatellite loci have null allele problems so we used an enrichment technique to isolate 21 new microsatellite loci for E. ephippiger. We present primer pairs for 10 polymorphic loci (3–11 alleles per locus). Observed heterozygosities at polymorphic loci ranged from 0.118 to 0.787, but several were significantly lower than expected. 相似文献
46.
WALTER MAJAK RUTH E. McDIARMID THOMAS W. POWELL ALBERT L. VAN RYSWYK DARRYL G. STOUT RICHARD J. WILLIAMS RICHARD E. TUCKER 《Plant, cell & environment》1979,2(4):335-340
Abstract. The alkaloids of reed canarygrass respond to changes in soil moisture and nitrogen fertility. Gramine and hordenine levels increased under field conditions of moisture deprivation and this effect was enchanced when nitrogen fertilizer was applied. The level of 5-methoxy-N-methyltryptamine was affected mainly by the nitrogen amendment. Exceptional alkaloid levels in reed canarygrass are interpreted in relation to climatic and plant osmotic parameters. Improved TLC fluorescence scanning procedures are presented for quantifying reed canarygrass alkaloids. 相似文献
47.
The fungicide imazalil has potential value for controlling post-harvest diseases caused by Alternaria alternata in pears, apples and persimmons. Imazalil was active in vitro on germination and hyphal growth (ED50) at 1.4 and 0.5 μg/ml, respectively. Protectant action of the fungicide lasted only 1 day after treatment. At 1000 μg/ml the fungicide inhibited development of Alternaria rot in inoculated apples at 0 °C and in naturally infected pears and persimmons at–1 °C. 相似文献
48.
RUTH KIEW F.L.S CHE SU IBRAHIM 《Botanical journal of the Linnean Society. Linnean Society of London》1982,84(2):79-102
The foliar anatomy of 15 Malaysian species of Chionanthus and 3 species of Olea is described and compared with particular reference to sclereids. The anatomy of the two genera is similar except that Chionanthus shows a wider range in sclereid form, eight kinds ofsclereid are recorded. Filiform sclereids are present in all Olea species and most Chionanthus species examined, additional kinds ofsclereid found in these Chionanthus species include astrosclereids, dendrosclereids, osteosclereids and polymorphic sclereids, with brachysclereids of several forms in the petiole. Quantity of sclereids is not related to coriaceousness, which is determined by leaf thickness. Anatomical characters do not support any major grouping of species within Chionanthus and provide further evidence that the sections, Eulinocitra and Ceranthus , are untenable. The distinction between the lepidote scales of Olea and the peltate hairs common to all oleaceous genera is discussed. 相似文献
49.
T. C. E. WELLS P. ROTHERY RUTH COX S. BAMFORD 《Botanical journal of the Linnean Society. Linnean Society of London》1998,126(1-2):39-48
Information taken from two long-term demographic studies on Orchis morio L. and Herminium monorchis (L.) R.Br, is used to explore some of the factors which influence flowering. The proportion of plants which flowered each year varied considerably between species, flowering in O. morio exceeding 40% in all years except one over an 18 year period; over a 30 year period (1966–95), the number of plants of Herminium in flower never exceeded 36% of the population and no inflorescences were produced in 1977 and 1991. The relationship between flowering in Herminium in a given year and the monthly rainfall and temperature for the current and 3 previous years was analysed using logistic regression. Best fits were obtained using data for the summer months in the previous year, with an increasing flowering rate with rainfall and a decline with temperature. It is hypothesized that drought and high temperatures in the summer reduce leaf area and cause premature senescence and the death of leaves, with the result that not enough carbohydrates are stored to enable plants to support or initiate inflorescences the following year. For species such as Orchis morio which produce leaves in the autumn and remain green, summer drought causes no problems as they have no above ground organs. Factors which influence flowering in this species are as yet unknown. 相似文献
50.