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1.
Abstract In much of its range Papilio glaucus L. has two forms of female, black and yellow, and the gene controlling the colour pattern is on the Y chromosome. Thus black mothers produce only black daughters and yellow mothers produce yellow daughters. Reasons are given to explain the occasional exceptions to this rule. The black female form mimics Battus philenor (L.), and an autosomal mutant is described in P.glaucus which is paralleled by a similar aberration in the model - a possible example of a model 'escaping' from a mimic and the mimic 'catching up' at one step.
Sex mosaics are readily seen in the black form of glaucus females and a numberare described from the Strecker collection. The probable cytogenetic constitution of these aberrations is discussed.
Hybrids are described between glaucus and its near relatives, P.rutulus Lucas, P.eurymedon Lucas and P.multicaudatus Kirby. These crosses produce mainly males but, by the use of ecdysterone, females have been obtained in the cross between the black female form of glaucus and the male of rutulus .  相似文献   

2.
ABSTRACT. Pupal diapause in the eastern tiger swallowtail. Papilio glaucus L., is obligatory or facultative depending on subspecies. The southern subspecies, P. g. glaucus has a facultative diapause, induced by a larval exposure to short photoperiods. In the northern subspecies. P.g. canadensis , diapause is obligatory, occurring in each generation. F*** hybrids inherit the diapause response of their father or respond differently from either parent. The incidence of diapause in hybrids was associated with sex, indicating that the diapause response may be determined by an X-linked gene.  相似文献   

3.
This study contrasts the ovipositional profiles of four members of the Papilio glaucus group, P. glaucus , P. multicaudatus , P. canadensis , and P. rutulus. We used seven choice oviposition bioassays containing leaves from hosts in seven plant families utilized by members of the P. glaucus group. Specifically, we contrast the overall ovipositional profiles of these species and their acceptance of a host in a novel plant family ( Populus tremuloides : Salicaceae) and a host in a putatively ancestral host plant family ( Liriodendron tulipifera : Magnoliaceae). Significant differences were observed between the ovipositional profiles of P. glaucus and P. multicaudatus relative to each other and to P. canadensis and P. rutulus. In contrast, no significant differences were observed between the ovipositional profiles of P. canadensis and P. rutulus , which were also the only species that accepted P. tremuloides. Unlike the acceptance of P. tremuloides , the acceptance of L. tulipifera was present throughout the group despite the inability of the larvae of most species in the group to utilize this host. These results support the prediction of the "hierarchical threshold model" that ancestral host plants are likely to be retained in the ovipositional hierarchy while novel hosts should only be accepted by derived populations.  相似文献   

4.
The radionuclide content was estimated in the soil of three black sand habitats in the Mediterranean coast of Egypt, namely, sand mounds and coastal sand planes and dunes. In addition, a total of 14 heavy minerals found in the soils were characterized. The soil to plant transfer of uranium and thorium was tested on three black sand species, namely, Cakile maritima Scop., Senecio glaucus L. and Rumex Pictus Forssk. The transfer of thorium and uranium radionuclides from the soil to plant is complex process that is subjected to many variables; among which are the organic matter and clay content of the soil, the type of radionuclides and plant species. The study revealed a strong negative relationship between uranium and thorium uptake by S. glaucus and R. pictus and the clay and organic matter content of soil. Concentration of thorium in the soil has a negative correlation with soil-to-plant transfer factor. The study results suggest the possibility of using black sand species for phytoremediation of soils contaminated with radioactive elements. The potentiality of S. glaucus as phytoremediator of radionuclides polluted soils is greater than R. pictus which in turn outweigh C. maritima.  相似文献   

5.
Abstract. 1. Recapture probabilities were analysed for individually marked black swallowtails, Papilio polyxenes F., and tiger swallowtails, P.glaucus L. (Lepidoptera: Papilionidae).
2. Recapture rates differed with sex and behaviour at time of capture for P.polyxenes , but not with age. For P.glaucus , only differences related to behaviour at time of capture were significant.
3. Black swallowtail males that were not physically restrained in identification had a recapture probability (73%) that was significantly higher than the 45% for males that were captured and handled. The higher rate was also exhibited by released, laboratory-reared males.
4. The capture effect was due to increased dispersal out of the areas and not to avoidance of capture or the capture site.  相似文献   

6.
Genetic variance-covariance structure of larval performance within and among spatio-temporal populations of the widely distributed, polyphagous tiger swallowtail butterfly, Papilio glaucus , is described. Performance traits were assessed for full-sibling families on three host species: Liriodendron tulipifera, Magnolia virginiana and Prunus serotina . Mean performance varied across hosts, indicating these hosts present unique developmental environments. Although full-sibling families significantly differed in plasticity of across-hosts response in three of the five spatio-temporal populations, additive genetic variation was mostly associated with P. serotina or pupal mass. The relative lack of heritable variation in rate and length of larval development on L. tulipifera and M. virginiana was consistent with an earlier study that established host-associated geographic differentiation of P. glaucus populations. Performance appeared relatively independent across hosts and thus genetic constraints cannot be casually invoked to explain persistence of local adaptation and host specialization in the face of extensive gene flow. I promote the hypothesis that gene flow among geographically distant populations is relatively restricted and that previously established, allozyme-based estimates of panmixia are confounded by effects of Pleistocene glaciations. Significant heterogeneity of variance-covariance structure among spatio-temporal P. glaucus populations supports an interpretation of restricted gene flow and relative evolutionary independence. Despite low precision of estimates of genetic parameters, local variance-covariance structure was remarkably consistent with expectations given the presumed evolutionary history of regional populations.  相似文献   

7.
In California valley grasslands, Avena fatua L. and other exotic annual grasses have largely displaced native perennial bunchgrasses such as Elymus glaucus Buckley and Nassella pulchra (A. Hitchc.) Barkworth. The invasion success and continued dominance of the exotics has been generally attributed to changes in disturbance regimes and the outcome of direct competition between species. Here, we report that exotic grasses can also indirectly increase disease incidence in nearby native grasses. We found that the presence of A. fatua more than doubled incidence of infection by barley and cereal yellow dwarf viruses (B/CYDVs) in E. glaucus. Because B/CYDV infection can stunt E. glaucus and other native bunchgrasses, the indirect effects of A. fatua on virus incidence in natives suggests that apparent competition may be an additional mechanism influencing interactions among exotic and native grasses in California. A. fatua's influence on virus incidence is likely mediated by its effects on populations of aphids that vector B/CYDVs. In our study, aphids consistently preferred exotic annuals as hosts and experienced higher fecundity on them, suggesting that the exotics can attract and amplify vector populations. To the best of our knowledge, these findings are the first demonstration that exotic plants can indirectly influence virus incidence in natives. We suggest that invasion success may be influenced by the capacity of exotic plant species to increase the pathogen loads of native species with which they compete.  相似文献   

8.
The taxonomy of diploid Mediterranean Senecio sect. Senecio (Asteraceae) is complex, owing to a recent species radiation, high morphological plasticity and occasional interspecific hybridization. A study was conducted to resolve the origin of a novel form of Senecio restricted to sand dunes in southern Sicily, Italy. This has been described previously as morphologically intermediate to Senecio gallicus and Senecio glaucus ssp. coronopifolius, indicating a possible hybrid origin, or as a variant of Senecio leucanthemifolius. Plants of this form grown in a glasshouse were morphologically intermediate to S. glaucus and S. leucanthemifolius, but were also similar to some cultivated individuals of S. gallicus. No evidence for a hybrid origin was obtained from a survey of random amplified polymorphic DNA variation; instead the plants surveyed were most closely allied to Tunisian S. glaucus. They were also polymorphic for the same set of cpDNA haplotypes present in Tunisian S. glaucus. We conclude that the Sicilian Senecio is a variant form of North African S. glaucus ssp. coronopifolius, which most probably dispersed to sand dunes in southern Sicily in the relatively recent past. The presence of several cpDNA haplotypes in this material indicates that there have been multiple introductions of the species to Sicily.  相似文献   

9.
Novel host usage may represent an initial step towards diversification or radiation onto novel hosts within an evolutionary lineage, particularly if a shift in host plant preference ranking takes place. Polyphagous stages of evolutionary lineages may represent transitional states in which novel host associations are more likely to develop, but may be more difficult to detect experimentally. The polyphagous sister species Papilio glaucus L. and Papilio canadensis (Lepidoptera: Papilionidae; these Papilio = Pterourus) are known to exhibit differences in host‐plant use, despite significant overlap in host‐use abilities, providing an opportunity to examine how host shifts in polyphagous species may occur and what the implications for future divergence may be. In particular, we were interested in (i) determining whether differences in oviposition behavior of these species were due to changes in specificity or shifts in host‐plant hierarchy, (ii) whether the varying preference for primary hosts also affected the preference for secondary hosts, and (iii) what the oviposition preferences of a new hybrid swarm population are. We examined more than 40 000 oviposition bouts from more than 400 P. glaucus, P. canadensis, and hybrid females placed in seven‐, three‐, or two‐choice assays. In each of the choice assays, leaves from plants in different plant families of varying suitability for P. glaucus and P. canadensis larvae were used. We found the primary difference between P. glaucus and P. canadensis to be limited to a Z‐linked shift in host rank hierarchy due to an acceptance of Populus tremuloides Michx. (Salicaceae) and reduced specificity for Liriodendron tulipifera L. (Magnoliaceae) in P. canadensis. In addition, we found the absence of the Z‐linked oviposition acceptance of P. tremuloides in a recently formed allochronically separated hybrid swarm population found in P. canadensis territory at the northern border of the P. glaucus and P. canadensis hybrid zone.  相似文献   

10.
11.
灰绿曲霉β-葡萄糖苷酶的分离及特性   总被引:1,自引:0,他引:1  
目的:利用灰绿曲霉EU7-22发酵产纤维素酶,从中分离到β-葡萄糖苷酶,分析其理化特性,确定其最佳活性条件。方法:灰绿曲霉EU7-22发酵液离心后,上清液经硫酸铵沉淀、Phenyl 6 Fast Flow(highsub)疏水层析和Sephacryl S-200凝胶层析,获得纯化的β-葡萄糖苷酶。结果:纯酶的比活性为5.1 IU/mg,得率为13.89%。SDS-PAGE凝胶电泳分析表明该酶是单亚基蛋白,其分子量为56.2 kDa。在pH4.0~6.0范围内,β-葡萄糖苷酶具有较高的稳定性,该酶的最适酶促反应pH为5.0。当β-葡萄糖苷酶在温度低于60℃的缓冲液中温育1 h后,酶活损失不大,表现了较好的稳定性;当该酶在温度高于60℃的缓冲液中温育1 h后,酶活迅速丧失。β-葡萄糖苷酶在70℃时具有最大催化活性。结论:灰绿曲霉EU7-22发酵产生的β-葡萄糖苷酶具有较高活性,具有分子量较小、最佳催化温度较高的特点。  相似文献   

12.
The cytotaxonomic characteristics of species of the genus Glyptotendipes (Chironomidae): G. glaucus Meigen, G. paripes Edwards, and G. barbipes (Staeger) are described. The studied material was collected from a fish pond at Go?ysz and a sewage retention pond at Chybie in Silesia. All the studied species have the chromosome set 2n = 8, but with many specific structural and functional changes. The cytogenetic data of G. glaucus showed that the studied specimens of this species have been produced by the introgressive hybridization of two sibling species: G. glaucus x G. pallens, and subsequent crossing-over in the hybrid chromosome CD. Owing to this process, the band pattern of chromosome arm D coincided with those of G. pallens. New aberrations (homo- and heterozygous deletions in arm G as well as heterozygous inversions in chromosome arm B) were detected in G. glaucus. Specific band sequences were discovered in chromosomes of G. paripes. The band patterns established in chromosomes AB and G of this species were identical with those of Siberian populations. The banding patterns of the polytene chromosomes of G. barbipes do not differ from the standard. However, high frequency of pericentric inversion of chromosome AB was established. Many new puffs were found in the polytene chromosomes of all the studied species. Their nucleolar organizer was very sensitive to environmental changes. In G. glaucus it appeared in three different states: very active, slightly active, and heterozygous state. The organic pollution existing in the sewage retention pond may contribute to possible mutations and chromosomal damage in Glypotendipes species. Structural and functional rearrangements of the polytene chromosomes of these species mobilized their genomes and provide for survival under polluted conditions.  相似文献   

13.
14.
Male butterflies aggregate at moist soil to acquire nutrients, a phenomenon termed “mud-puddling.” We studied the attraction of free-flying Papilio glaucus and Battus philenor swallowtails to dead decoys of those two species at artificial puddles moistened with NaCl solution. Both species landed preferentially at puddles with a decoy present rather than at unbaited puddles, demonstrating very strong local enhancement, a form of social facilitation. Papilio glaucus were attracted only to intraspecific decoys, whereas Battus philenor exhibited both intraspecific and interspecific attraction. Circular discs cut from the hindwings of male Battus were highly attractive to male Battus but completely unattractive to Papilio glaucus. The visual cues attractive to males in their search for salts differ between these two swallowtail species for unexplained reasons.  相似文献   

15.
The karyotype of experimentally obtained hybrids between the two closely related species Glyptotendipes pallens and Glyptotendipes glaucus is described. Hybridization was successful in one direction only ( G. pallens ♂ x G. glaucus ♀). The polytene chromosomes AB and EF of the hybrid show a more or less intimate pairing throughout their length. In the chromosomes CD in which an inversion occurs the characteristic loop is formed. The homologues of chromosome G are almost completely asynaptic. The localization of centromere heterochromatin was also studied. Centromere heterochromatin as well as intercalary heterochromatin could be observed in all chromosomes. By C banding analyses it could be shown that G. pallens has a telomeric chromosome G while in G. glaucus it is acrocentric. According to karyotype similarity it can be assumed that these two species have quite recently derived from a common ancestor since they still share much of their genomic organization. On the Black Sea coast (southeast part of Bulgaria) a natural hybridization zone between the sympatric species G. pallens and G. glaucus has been detected. The idea that hybridization between the two species might finally proceed to the formation of a new species by hybrid origin and introgression is discussed.  相似文献   

16.
Hybrid speciation, or the formation of a daughter species due to interbreeding between two parental species, is a potentially important means of diversification, because it generates new forms from existing variation. However, factors responsible for the origin and maintenance of hybrid species are largely unknown. Here we show that the North American butterfly Papilio appalachiensis is a hybrid species, with genomic admixture from Papilio glaucus and Papilio canadensis. Papilio appalachiensis has a mosaic phenotype, which is hypothesized to be the result of combining sex-linked traits from P. glaucus and P. canadensis. We show that P. appalachiensis' Z-linked genes associated with a cooler thermal habitat were inherited from P. canadensis, whereas its W-linked mimicry and mitochondrial DNA were inherited from P. glaucus. Furthermore, genome-wide AFLP markers showed nearly equal contributions from each parental species in the origin of P. appalachiensis, indicating that it formed from a burst of hybridization between the parental species, with little subsequent backcrossing. However, analyses of genetic differentiation, clustering, and polymorphism based on molecular data also showed that P. appalachiensis is genetically distinct from both parental species. Population genetic simulations revealed P. appalachiensis to be much younger than the parental species, with unidirectional gene flow from P. glaucus and P. canadensis into P. appalachiensis. Finally, phylogenetic analyses, combined with ancestral state reconstruction, showed that the two traits that define P. appalachiensis' mosaic phenotype, obligatory pupal diapause and mimicry, evolved uniquely in P. canadensis and P. glaucus, respectively, and were then recombined through hybridization to form P. appalachiensis. These results suggest that natural selection and sex-linked traits may have played an important role in the origin and maintenance of P. appalachiensis as a hybrid species. In particular, ecological barriers associated with a steep thermal cline appear to maintain the distinct, mosaic genome of P. appalachiensis despite contact and occasional hybridization with both parental species.  相似文献   

17.
对丽盲蝽属 (丽盲蝽亚属 )Lygocoris (subg .Lygocoris)的中国种类作了修订。文中共包括 19个种 ,其中有 12新种 ,1个中国新纪录种 ,并包括 1项新等级的认定。即暗胝丽盲蝽L .(L .)calligersp .nov .(正模 :四川峨眉山九老洞 ) ,程氏丽盲蝽L .(L .)chengisp .nov .(正模 :四川峨眉山大乘寺 ) ,晕斑丽盲蝽L .(L .)diffusomaculatussp .nov .(正模 :甘肃榆中兴隆山 ) ,淡色丽盲蝽L .(L .)dilutussp .nov .(正模 :甘肃夏河县合作 ) ,锈褐丽盲蝽L .(L .) ferrugineussp .nov .(正模 :云南哀牢山 ) ,褐盾丽盲蝽L .(L .) fuscoscutel latus (Reuter ,190 6 )stat .nov .[由L .(L .)striicornisvar.fuscoscutellatus升为种级阶元 ],广西丽盲蝽L .(L .) guangxiensissp .nov .(正模 :广西龙胜 ) ,东亚丽盲蝽L .(L .)idoneus(Linnavuori,196 3) (中国新纪录种 ) ,完脊丽盲蝽L .(L .)integricarinatussp .nov .(甘肃榆中麻家寺 ) ,林氏丽盲蝽L .(L .)linnavuoriisp .nov .(云南哀牢山簸箕坝 ) ,长翅丽盲蝽L .(L .)longipennis (Reuter ,190 6 ) ,斑盾丽盲蝽L .(L .)maculis cutellatussp .nov .(四川理县刷经寺 ) ,原丽盲蝽L .(L .) pabulinus (Linnaeus ,176 1) ,红盾丽盲蝽L .(L .)rufiscutellatussp .nov .(甘  相似文献   

18.
Bossart JL 《Oecologia》2003,135(3):477-486
Covariance between preference and performance was quantified for Papilio glaucus strains derived from a locally monophagous Florida population and a locally polyphagous Ohio population. I used two-choice assays to assess relative host preferences of mothers for plant species that represent reciprocal normal and novel hosts for each population (i.e., Liriodendron tulipifera and Magnolia virginiana) and a split-brood design to quantify relative performance of their progeny on each host. Covariance between preference and proxies of performance was detected independently within each population, which is a level of genetic structure at which such covariance has rarely been documented. These results support the hypothesis that preference-performance covariance can exist in populations that have no obvious internal host-associated structure. In the Ohio strain, all proxies of performance (larval duration, pupal mass, relative growth rate, and survival) were significantly correlated with relative preference for the normal host, L. tulipifera. In the Florida strain, however, only pupal mass was correlated with maternal preference, and this correlation was not in the direction expected. Progeny that attained the heaviest mass were derived from mothers that preferred L. tulipifera, the locally rare host. The nature of the preference-performance links was not in the manner predicted by conventional optimal oviposition theory, whereby host-associated tradeoffs have been considered an implicit element. Relative performance was congruent across hosts, regardless of whether mothers preferred L. tulipifera, M. virginiana, or neither host. After considering possible genetic and nongenetic explanations that could account for preference-performance covariance in P. glaucus, I conclude that this covariance has a genetic basis. Likely, multiple genetic control mechanisms (e.g., pleiotropy and co-adaptation) integrate at the level of different trait combinations and/or a particular trait combination to generate observed patterns.  相似文献   

19.
The species Rubus glaucus, also known as the Andean or "Castilla" blackberry, is one of nine edible species of this genus that grow naturally in Central and South America. In Colombia, this species is the most important of all Rubus species for agricultural and commercial purposes. We used 20 SSRs developed for other Rubus species to characterize 44 Colombian R. glaucus genotypes, collected from eight different departments, and to look for molecular differences between thornless and thorny cultivated blackberries. Eighty-two bands were obtained from 28 loci. The genotypes were classified into eight populations, corresponding to collection sites. The mean number of polymorphic alleles per locus in all populations and genotypes ranged from 1.857 to 2.393. Samples collected from Valle del Cauca, Quindío, Caldas, and Risaralda departments had the highest heterozygosity values. The finding of exclusive bands from R. glaucus genotypes from Valle del Cauca, Quindío, and Caldas demonstrates genetic and molecular differentiation between thorny and thornless Andean blackberries.  相似文献   

20.
The reasons that the northern tiger swallowtail butterfly Papilio canadensis does not move south of the Great Lakes hybrid zone, where it meets P. glaucus , may be largely due to natural temperature-induced stress on diapausing pupae. Temperatures of 36°C for only four days killed all P. canadensis (from northern Michigan) and most of the Papilio troilus , a species that lives south of the hybrid zone (sympatrically with P. glaucus ). In contrast, interspecific hybrids ( P. glaucus mother× P. canadensis father) had significant adult eclosion or pupal survival at both 30° and 36°C. All surviving hybrid pupae were only females (the heterogametic sex, which are known to express the prolonged diapause due to Haldane effects).
The southern species, P. troilus , had almost all (81%) normal (non-deformed) adults eclose at 30°C, whereas only 20% of the P. canadensis females and ca 30% of the P. canadensis males eclosed to produce non-deformed adults. Unlike the case with P. troilus and P. canadensis , no hybrid females eclosed at 30°C (only males did). Unlike P. troilus and P. canadensis pupae, hybrid (female) pupae remain viable, some of which have already successfully emerged after the chamber experiments.
A follow-up study using P. glaucus , P. canadensis (from Vermont), and their hybrids with more normal lower thermal regimes included (27°, 30°, 33°, and 36°C) again showed higher hybrid survival as uneclosed (living) pupae at 36°C. In addition, P. glaucus and P. canadensis showed high mortality and wing deformity of eclosing adults at 36°C, suggesting that geographic source of the P. canadensis may reflect differential tolerances of the extreme 36°C temperature.  相似文献   

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