Crossing relationships among seven members of the group of Aedes scutellaris (Walker) (Diptera: Culicidae)

AbstractA rickettsia-free (aposymbiotic) stock of Aedes polynesiensis Marks (POLY-A) was crossed with (a) three symbiont-infected stocks of A. polynesiensis (POLY-S from Samoa and POLY-N and POLY-T from Fiji), (b) A. pseudoscutellaris (Theo.) (PSE) from Fiji, (c) A. alcasidi Huang (ALC), A. scutellaris katherinensis Woodhill (KATH), A. s. malayensis Colless (MAL) and A. s. scutellaris (Wlk.) (SCUT), which occur to the west of Fiji and (d) an aposymbiotic stock of A. cooki Belkin (CO) from Niue. It was bidirectionally compatible with CO, but in all other crosses compatibility was high when POLY-A was the male parent and very low when it was the female parent. Backcross data suggested that the crossing type was maternally inherited. ALC and KATH were bidirectionally compatible; both were virtually incompatible with POLY-S and PSE, compatible with SCUT when the latter was the female parent, and compatible with CO when the latter was the male parent. POLY-S females were moderately compatible with a third Fijian stock of A. polynesiensis (POLY-V), and POLY-N and POLY-V were compatible with PSE. If, as in Culex pipiens L., rickettsia-like symbionts are responsible for cytoplasmic incompatibility, then aposymbiotic males should cross successfully with symbiont-infected females, whereas the reciprocal cross should be unsuccessful. Since PSE, MAL and SCUT contain symbionts, their crossing relationships are consistent with the hypothesis. However, ALC and KATH appear to be aposymbiotic and their crossing relationships conflict with the hypothesis. There is little evidence of behavioural barriers to mating between species, but whereas male hybrids of two eastern species were capable of normal insemination, male hybrids between western and eastern species gave very low insemination rates. The egg-hatch rates from backcrosses of female hybrids between western and eastern species to the parents were reduced.

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Male parent birds exert more effort to reproduce in two desert passerines

Avian Research ◽

10.1186/s40657-021-00273-6 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Donghui Ma ◽

Mengjie Lu ◽

Zhichang Cheng ◽

Xingnan Du ◽

Xiaoyu Zou ◽

...

Keyword(s):

Reproductive Output ◽

Female Parent ◽

Northwest China ◽

Reproductive Behaviour ◽

Male Parent ◽

Hatching Rate ◽

Feeding Rates ◽

Passerine Species ◽

Arid Desert ◽

Habitat Environment

Abstract Background Parental investment by birds is limited by the habitat environment, and a male parent increases its effort to reproduce in birds that live in high-altitude areas. Methods A study of the reproductive behaviour of the Saxaul Sparrow (Passer ammodendri) and the Isabelline Shrike (Lanius isabellinus) was carried out at the Gansu An’xi Extremely Arid Desert National Nature Reserve in northwest China to determine the reproductive input of passerine species in desert habitats. Results In Saxaul Sparrows, compared to the female parent, the male parent exhibited a significantly higher frequency of nest-defense behaviour (chirping and warning) during nesting, hatching and feeding periods. In addition, in comparison to the female parent, the male parent exhibited almost equal frequencies of nesting and incubation but fed nestlings significantly more times. Similar to the male sparrows, the feeding rates of the male Isabelline Shrikes were significantly higher than those of the females. The hatching rate and fledging rate of the Saxaul Sparrow on average in this study were 81.99 and 91.92%, respectively, while those of the shrike were 69.00 and 96.53%, respectively. Conclusions These two different passerine species living in the same desert environment exhibited the same trend in their reproductive investments. Adapting to desert environments is a strategy that may have evolved in passerines where male parent birds put more effort than females into reproduction to ensure high reproductive output.

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Eradication of Culex pipiens fatigans through Cytoplasmic Incompatibility

Nature ◽

10.1038/216383a0 ◽

1967 ◽

Vol 216 (5113) ◽

pp. 383-384 ◽

Cited By ~ 259

Author(s):

H. LAVEN

Keyword(s):

Culex Pipiens ◽

Cytoplasmic Incompatibility ◽

Culex Pipiens Fatigans

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Influence of the microencapsulated pheromone from aged infusion as an oviposition medium of the West Nile virus vector Culex pipiens

Parasitology Research ◽

10.1007/s00436-008-1282-z ◽

2008 ◽

Vol 104 (5) ◽

pp. 1005-1009 ◽

Cited By ~ 3

Author(s):

Antonios Michaelakis ◽

Anastasia. P. Mihou ◽

George Koliopoulos ◽

Elias. A. Couladouros

Keyword(s):

West Nile Virus ◽

Culex Pipiens ◽

Virus Vector ◽

The West ◽

West Nile

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Efficacy of Two Monoterpenoids, Carvacrol and Thymol, and Their Combinations against Eggs and Larvae of the West Nile Vector Culex pipiens

Molecules ◽

10.3390/molecules24101867 ◽

2019 ◽

Vol 24 (10) ◽

pp. 1867 ◽

Cited By ~ 14

Author(s):

Mohammad Reza Youssefi ◽

Mohaddeseh Abouhosseini Tabari ◽

Aryan Esfandiari ◽

Sohrab Kazemi ◽

Ali Akbar Moghadamnia ◽

...

Keyword(s):

Culex Pipiens ◽

Mosquito Control ◽

Fixed Ratio ◽

Botanical Insecticides ◽

Ratio Method ◽

Insect Vector ◽

The West ◽

West Nile ◽

Lc50 Value ◽

Insecticidal Efficacy

Background: Insect vector control is facing the challenges of resistance development and environmental hazards caused by synthetic pesticides. This has led to a considerable market opportunity for botanical insecticides. In this scenario, our study investigated the potential of selected bioactive monoterpenoids, carvacrol and thymol, as safe and effective tools to control the West Nile vector Culex pipiens. Furthermore, the combined effect of thymol-carvacrol mixtures and their possible interactions were assessed. Methods: For determining larvicidal and ovicidal 50% lethal concentration (LC50), each monoterpenoid was tested at different concentrations (5–500 mg/L). Then, the fixed ratio method was used for evaluating their combinational efficacy. Results: Carvacrol was more toxic against larvae of Cx. pipiens, with a LC50 value of 14 mg/L, whereas thymol exhibited a LC50 value of 49 mg/L. Comparable trends of efficacy were observed when toxicity on Cx. pipiens eggs was investigated, with LC50 values of 7 and 13 mg/L for carvacrol and thymol, respectively. In combinational toxicity assays, the mixture thymol-carvacrol at 1:4 ratio achieved a synergistic effect against larvae of Cx. pipiens, whereas an additive effect was observed on eggs. Other ratios showed antagonistic effects. Conclusions: Overall, our findings pointed out that the 1:4 ratio of thymol-carvacrol blend can enhance the insecticidal efficacy on Cx. pipiens young instars and can be considered further as active ingredient for developing botanical insecticides to be used in mosquito control operations.

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Larvicidal activity of spinosad and its impact on oviposition preferences of the West Nile vector Culex pipiens biotype molestus – A comparison with a chitin synthesis inhibitor

Parasitology International ◽

10.1016/j.parint.2019.04.014 ◽

2020 ◽

Vol 74 ◽

pp. 101917 ◽

Cited By ~ 3

Author(s):

Antonios Michaelakis ◽

Dimitrios P. Papachristos ◽

Christos I. Rumbos ◽

Giovanni Benelli ◽

Christos G. Athanassiou

Keyword(s):

Larvicidal Activity ◽

Culex Pipiens ◽

Chitin Synthesis ◽

Synthesis Inhibitor ◽

The West ◽

West Nile ◽

Oviposition Preferences ◽

Chitin Synthesis Inhibitor

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Variation in adult longevity of Culex pipiens f. pipiens, vector of the West Nile Virus

Parasitology Research ◽

10.1007/s00436-014-4152-x ◽

2014 ◽

Vol 113 (11) ◽

pp. 4315-4319 ◽

Cited By ~ 14

Author(s):

S. S. Andreadis ◽

O. C. Dimotsiou ◽

M. Savopoulou-Soultani

Keyword(s):

West Nile Virus ◽

Culex Pipiens ◽

Adult Longevity ◽

The West ◽

West Nile

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Rapid evolution of Wolbachia incompatibility types

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2012.1368 ◽

2012 ◽

Vol 279 (1746) ◽

pp. 4473-4480 ◽

Cited By ~ 11

Author(s):

Olivier Duron ◽

Jennifer Bernard ◽

Célestine M. Atyame ◽

Emilie Dumas ◽

Mylène Weill

Keyword(s):

Reproductive Success ◽

Dynamic Process ◽

Culex Pipiens ◽

Cytoplasmic Incompatibility ◽

Rapid Evolution ◽

The Self ◽

Isofemale Lines ◽

Individual Host ◽

Gradual Process ◽

Self Compatibility

In most insects, the endosymbiont Wolbachia induces cytoplasmic incompatibility (CI), an embryonic mortality observed when infected males mate either with uninfected females or with females infected by an incompatible Wolbachia strain. Although the molecular mechanism of CI remains elusive, it is classically viewed as a modification–rescue model, in which a Wolbachia mod function disables the reproductive success of the sperm of infected males, unless eggs are infected and express a compatible resc function. The extent to which the modification–rescue model can predict highly complex CI pattern remains a challenging issue. Here, we show the rapid evolution of the mod–resc system in the Culex pipiens mosquito. We have surveyed four incompatible laboratory isofemale lines over 50 generations and observed in two of them that CI has evolved from complete to partial incompatibility (i.e. the production of a mixture of compatible and incompatible clutches). Emergence of the new CI types depends only on Wolbachia determinants and can be simply explained by the gain of new resc functions. Evolution of CI types in Cx. pipiens thus appears as a gradual process, in which one or several resc functions can coexist in the same individual host in addition to the ones involved in the self-compatibility. Our data identified CI as a very dynamic process. We suggest that ancestral and mutant Wolbachia expressing distinct resc functions can co-infect individual hosts, opening the possibility for the mod functions to evolve subsequently. This gives a first clue towards the understanding of how Wolbachia reached highly complex CI pattern in host populations.

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TOWER POPLAR

Canadian Journal of Plant Science ◽

10.4141/cjps80-153 ◽

1980 ◽

Vol 60 (3) ◽

pp. 1055-1056 ◽

Cited By ~ 1

Author(s):

W. G. RONALD

Keyword(s):

Growth Form ◽

Female Parent ◽

Male Parent ◽

Columnar Growth

Populus × canescens ’Tower’ combines qualities of improved root-ability and foliage found in the female parent, P. alba L., with hardiness and columnar growth form of its male parent, P. tremula L. ’Erecta’. The distinctly columnar growth form makes the tree useful for landscape and shelterbelt applications. It is readily propagated from root and softwood cuttings.

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