共查询到20条相似文献,搜索用时 15 毫秒
1.
Kazuki Miura Takehiko Yamanaka Yoshito Suzuki Yohsuke Tagami Andrew Paul Davies 《Population Ecology》2009,51(2):245-252
Parthenogenesis-inducing (PI) Wolbachia bacteria are reproductive parasites that cause infected (W
+) female haplodiploid parasitoids to produce daughters without fertilization by males. Theoretically, PI Wolbachia infection should spread to fixation within Trichogramma populations as males are no longer required to produce female offspring. Infections in some naturally occurring Trichogramma populations are, however, maintained at frequencies ranging from 4 to 26%. Here we describe discrete equation models to examine
if the PI Wolbachia infection in Trichogramma populations can be maintained at relatively low frequencies by mating regularity. Model outcomes suggest the probability
of W
+ females mating could stabilize Wolbachia infection frequency at low levels in Trichogramma populations. The primary mechanism maintaining low-level PI Wolbachia infection in Trichogramma populations is reducing the survivorship from egg to adult in infected relative to uninfected females. The model successfully
demonstrates that the relatively low PI Wolbachia infection frequency in host populations can be maintained by fertilization, or male rescue, of infected eggs, which avoids
potentially hazardous gamete duplication that occurs during Wolbachia-induced parthenogenesis. 相似文献
2.
Transmission of conidia between mates of the Asian longhorned beetle, Anoplophora glabripennis (Motschulsky) (Coleoptera: Cerambycidae), was studied using two isolates of the entomopathogenic fungus Metarhizium brunneum Petch (Hypocreales: Clavicipitaceae) (formerly M. anisopliae). After one beetle was inoculated and caged with a mate for 6 h, conidia were rinsed off each beetle using Tween-80 and pentane
to count conidia transferred. Treated males transmitted more conidia to females than treated females transferred to males.
Untreated partners did not die as quickly as their inoculated mates, but died significantly faster than controls. For beetles
inoculated with ARSEF 7711, the difference in time to death between inoculated beetles and their untreated mates was shorter
when males were inoculated than when females were inoculated. We hypothesize that greater conidial transmission from males
to females was due to their relative positions during copulation and the prolonged post-copulatory mate-guarding characteristic
of males. 相似文献
3.
Richard Stouthamer James E Russell Fabrice Vavre Leonard Nunney 《BMC evolutionary biology》2010,10(1):229
Background
The maternally inherited, bacterial symbiont, parthenogenesis inducing (PI) Wolbachia, causes females in some haplodiploid insects to produce daughters from both fertilized and unfertilized eggs. The symbionts, with their maternal inheritance, benefit from inducing the production of exclusively daughters, however the optimal sex ratio for the nuclear genome is more male-biased. Here we examine through models how an infection with PI-Wolbachia in a previously uninfected population leads to a genomic conflict between PI-Wolbachia and the nuclear genome. In most natural populations infected with PI-Wolbachia the infection has gone to fixation and sexual reproduction is impossible, specifically because the females have lost their ability to fertilize eggs, even when mated with functional males. 相似文献4.
Vesta Skrodenytė-Arbačiauskienė Nijolė Kazlauskienė Milda Zita Vosylienė Tomas Virbickas 《Central European Journal of Biology》2012,7(5):878-885
Experimental studies of infection transmission via water from infected to healthy fish were conducted. The dark-brown bacterial colonies typical for Aeromonas salmonicida on tryptone soya agar (TSA) have been isolated and counted (from 3.0±0.6×102 to 3.5±0.5×105 c.f.u. g−1) from the internal organs of naturally infected (NI) and experimentally infected (EI) perch and sea trout. No significant differences in dark-brown bacterial counts were detected between EI perch and EI sea trout. The assessment and comparison of the alterations of the biological parameters of EI European perch and sea trout with bacterium Aeromonas salmonicida subsp. salmonicida with naturally infected perch were conducted. No mortality was recorded in groups of EI perch and sea trout. Whereas, the mortality of NI perch (collected from the main sites of outbreak of disease) was observed from the second day of the experiments. Changes in morphophysiological parameters of EI perch and sea trout were similar. Different alterations in blood cell parameters of EI fish were observed, and the most noticeable was the decrease (P≤0.01) in white blood cell count (WBC) of EI perch and sea trout. Based on these results it can be deduced that there is infection transmission of bacterium A. salmonicida from European perch via water to other fish species. 相似文献
5.
D. Yu. Panteleev I. I. Goryacheva B. V. Andrianov N. L. Reznik O. E. Lazebny A. M. Kulikov 《Russian Journal of Genetics》2007,43(9):1066-1069
To determine biologically important effects of the cytoplasmic endosymbiont Wolbachia, two substrains of the same Drosophila melanogaster strain have been studied, one of them infected with Wolbachia and the other treated with tetracycline to eliminate the bacterium. Females of D. melanogaster infected with Wolbachia are more resistant to the fungus Blauveria bassiana (an insect pathogen) than uninfected females; infected females also exhibited changes in oviposition substrate preference. Males infected with the bacterium are more competitive than uninfected males. The possible role of Wolbachia in the formation of alternative ecological strategies of D. melanogaster is discussed. 相似文献
6.
Yuki Nakamura Fumiko Yukuhiro Masaya Matsumura Hiroaki Noda 《Applied Entomology and Zoology》2012,47(3):273-283
Cytoplasmic incompatibility (CI) is a reproductive phenotype induced by bacterial endosymbionts in arthropods. Measured as a reduction in egg hatchability resulting from the crossing of uninfected females with bacteria-infected males, CI increases the frequency of bacteria-infected hosts by restricting the fertilization opportunities of uninfected hosts in populations. Wolbachia, a type of alpha-proteobacteria, is well known as a CI inducer in a wide range of arthropod species, while Cardinium, a member of the phylum Bacteroidetes, is known to cause CI in one wasp and three spider mite species. In this study, dual infection with Cardinium and Wolbachia induced strong CI in a single host, Sogatella furcifera (Horváth), a planthopper species that is naturally infected with both bacteria. Specifically, infection with Cardinium alone was found to cause a 76 % reduction in egg development, and dual infection with Cardinium and Wolbachia a 96 % reduction, indicating that Cardinium induces CI and the dual infection raises the CI level. This study was the first to document reproductive alteration by Cardinium in a diploid host species. 相似文献
7.
C. Tollenaere L. Rahalison M. Ranjalahy J.-M. Duplantier S. Rahelinirina S. Telfer C. Brouat 《EcoHealth》2010,7(2):242-247
In Madagascar, the black rat, Rattus rattus, is the main reservoir of plague (Yersinia pestis infection), a disease still responsible for hundreds of cases each year in this country. This study used experimental plague
challenge to assess susceptibility in wild-caught rats to better understand how R. rattus can act as a plague reservoir. An important difference in plague resistance between rat populations from the plague focus
(central highlands) and those from the plague-free zone (low altitude area) was confirmed to be a widespread phenomenon. In
rats from the plague focus, we observed that sex influenced plague susceptibility, with males slightly more resistant than
females. Other individual factors investigated (weight and habitat of sampling) did not affect plague resistance. When infected
at high bacterial dose (more than 105 bacteria injected), rats from the plague focus died mainly within 3–5 days and produced specific antibodies, whereas after
low-dose infection (< 5,000 bacteria), delayed mortality was observed and surviving seronegative rats were not uncommon. These
results concerning plague resistance level and the course of infection in the black rat would contribute to a better understanding
of plague circulation in Madagascar. 相似文献
8.
I. D. Alexandrov M. V. Alexandrova I. I. Goryacheva N. V. Rochina E. V. Shaikevich I. A. Zakharov 《Russian Journal of Genetics》2007,43(10):1147-1152
To understand specific symbiotic relationships ensuring stable existing of the bacterium Wolbachia in laboratory strains of Drosophila melanogaster, the imago lifespan and senescence rate, as well as competitiveness, have been evaluated as components of fitness in females from the following laboratory strains: (1) inbred strain 95 infected with Wolbachia; (2) two uninfected strains obtained by tetracycline treatment that were genetically similar to strain 95; and (3) two control, uninfected, wild-type laboratory strains that were used to assess the possible effects of the antibiotic on the studied characters in the absence of Wolbachia. The results have shown that infected females have longer lifespan and competitiveness than females with the same genotype uninfected with Wolbachia. The increase in the senescence and mortality rates with age was also slower in infected females. It is noteworthy that tetracycline does not affect the lifespan of females from the two control, uninfected, wild-type strains. Therefore, the antibiotic is not the cause of the positive changes in fitness that were observed in infected females. The obtained results are the first direct evidence that the relationships in the Wolbachia-D. melanogaster symbiotic system are mutualistic rather than parasitic, at least in micropopulations adapted to laboratory conditions. 相似文献
9.
D. C. Peñalva-Arana Kenneth Forshay Pieter T. J. Johnson J. R. Strickler Stanley I. Dodson 《Hydrobiologia》2011,668(1):147-154
Zooplankters are hosts to numerous endo- and ectoparasites, some of which have dramatic impacts on their hosts. Epizootics
on zooplankton are probably more widespread in lake systems than it is currently known, and few studies have explored the
direct and indirect importance of parasitism in aquatic food webs. In addition, our understanding of the sublethal effects
of parasitic infections on host organisms and populations is limited. We used a novel electro-chemical based technique to
measure in the outflow of the feeding current changes in the beat rate of the thoracic appendages in female Daphnia pulicaria. We observed simultaneously the heart rates and compared chytrid infected animals with uninfected gravid and non-gravid ones.
We found in uninfected animals a thoracic beat rate of 3.81 ± 018 Hz and a heart rate of 4.67 ± 0.42 Hz. Gravid daphnids had
a 14% lower thoracic beat rate (3.27 ± 0.30 Hz) than non-gravid females while the heart rate did not significantly differ
(4.48 ± 0.28 Hz). In contrast, infected animals showed a 22% lower thoracic beat rate (2.96 ± 0.47 Hz) and a 36% lower heart
rate (2.98 ± 0.5 Hz) when compared with uninfected non-gravid females. We discuss the ways Daphnia are affected by Polycaryum leave infections on the individual and population level. 相似文献
10.
Males of the solitary bee Amegilla (Asarapoda) paracalva employ two mate-locating tactics: aggressive defense of sites from which virgin females are emerging and patrolling flower
patches that are visited by conspecific females. At one study site, a single male was able to control an entire emergence
area for one or more days. Multiple males patrolled one flower patch, interacting aggressively on occasion but no one individual
was able to monopolize this resource. Territorial males at the emergence site secured mates by waiting by tunnels for receptive
virgin females to emerge after metamorphosis. Males patrolling the flower patch pounced upon flower visiting conspecifics
and mated with receptive females there. Territorial males at the emergence site were larger than average individuals, probably
because of the advantage larger males have when grappling with opponents. Flower patrolling males were smaller than territorial
males at the emergence sites, perhaps because of the advantages gained by these males from rapid, agile flight. 相似文献
11.
Here we describe the natural infection rate in China of Haemaphysalis qinghaiensis with four Piroplasma species, namely Theileria uilenbergi, T. luwenshuni, T. sinensis and Babesia
motasi. Specifically, a nested PCR was designed based on 18S ribosomal RNA genes and its specificity and sensitivity were established.
The result showed that 62 flat adult field H. qinghaiensis ticks (27 females and 35 males) out of 136 (55 females and 81 males) were infected by one or more parasites. All 62 (45.6%)
were infected with T. uilenbergi; nine (five males and four females; 6.6%) were infected with T. luwenshuni; two (1.5%) females were infected with T. sinensis; and one (0.7%) male was infected with B. motasi. Twelve (19.4%) were infected with more than one pathogen. There was no significant difference in infection rate between
males and females. The high figure 45.6% Theileria infection rate indicates the serious prevalence of theileriosis; while the presence of T. sinensis and B. motasi implies the potential existence of the corresponding diseases in the area studied. 相似文献
12.
Agnieszka Pociecha 《Polar Biology》2007,30(6):731-734
The Antarctic crustacean Branchinecta gaini (Branchiopoda, Anostraca) occurs in nine fresh water lakes near the Polish H. Arctowski Station. In one of the largest, Lake
Wujka (Lake Uncle in English), we determined how temperatures affect its respiration and whether this is sex dependent. Experiments
were carried out on males and females bearing eggs over a range of temperatures from 0.5 to 10°C. An ANOVA showed that while
the amount of oxygen consumed increased with temperature (P < 0.001) males consumed more oxygen than similarly-sized females bearing eggs (P < 0.001). 相似文献
13.
Three mite species are frequently found on vegetable crops in Italy: the pest Tetranychus urticae Koch (Acari: Tetranychidae), the predator Neoseiulus californicus (McGregor) (Acari: Phytoseiidae) and the unspecialised feeder Tydeus californicus (Banks) (Acari: Tydeidae). In laboratory trials, the direct and residual effects of six insecticides recommended for the control of aphids, whiteflies and thrips in vegetable crops, (Biopiren® plus (pyrethrins), Confidor® (imidacloprid), Oikos® (azadirachtin), Plenum® (pymetrozine), Naturalis® (Beauveria bassiana) and Rotena® (rotenone)), were evaluated for the three mite species. All the products affected the mites and their effect was often favourable towards T. urticae and unfavourable towards N. californicus and T. californicus. Rotenone was more toxic to eggs than females of T. urticae. It was highly toxic to N. californicus and caused the death of all treated females of T. californicus. Pyrethrins and imidacloprid increased T. urticae fecundity, but decreased fecundity of N. californicus. Imidacloprid decreased T. californicus fecundity more than pyrethrins. Beauveria bassiana was not toxic to T. urticae and T. californicus, but induced high mortality in the progeny of treated females of N. californicus. Azadirachtin and pymetrozine were the least toxic to T. urticae and N. californicus, but decreased production of larvae in T. californicus. Implications for integrated pest management on vegetables are discussed. 相似文献
14.
Pia Untalan Olafson Kevin B. Temeyer John H. Pruett 《Experimental & applied acarology》2011,53(2):147-165
15.
K. P. Singh R. K. Jaiswal Niranjan Kumar 《World journal of microbiology & biotechnology》2007,23(2):291-294
Summary
Catenaria anguillulae parasitized and killed the eggs and second stage juveniles (J2) of Meloidogyne graminicola under natural conditions. The percentage of infection in eggs was higher than J2 of M.␣graminicola, which ranged between 0–50.3% and 0–18.9% in 2004 and 0–46.6% and 0–21.7% in 2005, respectively. The higher parasitism of
eggs and J2 was recorded from those fields in which plants were severely infected with M. graminicola. The degree of parasitism of eggs and J2 by C. anguillulae varied with severity of root knot disease. The fields with a higher root gall index recorded a higher percentage of infection
in eggs and J2 of M. graminicola. In general, old galls when teased and incubated, recorded higher parasitism of eggs and juveniles than young galls. 相似文献
16.
A leaf disc bioassay was employed to examine the effects of temperature and predator age on functional response of an acarophagous
thrips, Scolothrips takahashii Priesner, to hawthorn spider mite, Tetranychus viennensis Zacher, in the laboratory. The results indicated that the predatory thrips exhibited type-II functional responses against
the mites under various temperatures, and that females are more voracious than males. Analysis showed that temperature had
significant effects on the predatory capacity of adult thrips over the range of 20–35 °C. Attack rate in females linearly
increased with temperature while in males it was independent of temperature. Handling times in both males and females decreased
linearly with increasing temperature. Extended response models describing the functional response with temperature incorporated
as a parameter were developed, yielding an estimated maximum numbers of prey attacked at four temperatures were 38.38, 55.06,
71.74 and 88.42 eggs per day for females, and 15.11, 26.11, 37.11 and 48.01 eggs per day for males, respectively. The age
of predator affected both the type of the functional response shown and the magnitude of predation by S.␣takahashii on the spider mite. Females of various ages exhibited Type-II functional responses with similar attack rates, but handling
time prolonged linearly as age increased: the handling times in 15- and 18-d-old females were significantly longer than in
6-d-old thrips. However, Type-I functional responses were determined for males aged 12 d or more; the maximum number of prey
eaten in 24 h decreased as age increased. The implications of the results for the management of hawthorn spider mite are discussed. 相似文献
17.
Xing-Ping Liu Jing Xu Hai-Min He Xian-Ju Kuang Fang-Sen Xue 《Journal of Insect Behavior》2011,24(2):83-93
The influence of male age on female mate preference and reproductive performance in the cabbage beetle, Colaphellus bowringi was examined, using male and female adults of varying ages (young, middle-aged and old) after a single mating. In a simultaneous
choice test, females of all age class preferentially mated with middle-aged males. Mating duration was positively related
to male age. Longevity of females was not significantly affected by male age. Young females paired to middle-aged males had
significantly higher egg production than those paired to old males, and the eggs of females paired to middle-aged males exhibited
significantly higher hatching success than the eggs of females mated to young or old males. These results suggest that middle-aged
males are more advantageous for female fitness than young and old males. 相似文献
18.
Isopods Asellus hilgendorfi were collected from a small lake in northern Japan and examined to determine whether their body size and reproduction were
affected by infection with larval acanthocephalans (Acanthocephalus sp.). Seasonal changes in the breeding ratio of isopods and the prevalence of larval acanthocephalan infection showed a reverse
trend. Acanthocephalan larvae occurred mainly in males and immature females and were rarely found in mature females. In late
immature females, the body size, as indicated by the width of the pleotelson, of infected isopods was significantly larger
than that of uninfected ones. These results suggest that acanthocephalans can prevent female isopods from attaining sexual
maturity and increasing their body size.
Received: January 9, 2002 / Accepted: December 16, 2002
Acknowledgments We thank Professor Shōichi Saito, Faculty of Education, Hirosaki University, for his encouragement of the present study.
Thanks are also due to the Iwasaki Village Office and the Fukaura Forestry Office for giving us permission for the survey.
Correspondence to:A. Ohtaka 相似文献
19.
The aim of this study was to determine if individual ticks among the progeny of a single female Rhipicephalus (Boophilus) microplus tick removed from cattle under natural conditions are the result of mating with one or several males. To this end, simulations
were run using an existing dataset of genotypes from 8 microsatellite loci to predict the number of samples required and the
best locus. Subsequently, 14–22 progeny from each of 15 engorged female ticks removed from three cows, and the engorged females
themselves, were genotyped for the BmM1 locus and the minimum number of potential male parents was determined for each progeny
group. Of the 15 progeny groups, 10 must have been sired by more than one male, as indicated by the presence of five unique
alleles among the progeny or three unique alleles that could not have been contributed by the female. This finding demonstrates
multiple paternity in R. microplus. 相似文献
20.
I. Yu. Rauschenbach N. V. Adonyeva E. K. Karpova Yu. Yu. Ilinsky N. E. Gruntenko 《Russian Journal of Genetics》2018,54(7):871-873
The effect of gonadotropic hormones (juvenile (JH) and 20-hydroxyecdysone (20E)) on heat stress resistance was for the first time studied in wild type D. melanogaster line females infected with different genotypes of the Wolbachia pipientis alpha-proteobacterium. It was found that an experimental increase in JH level induces a decrease in the heat stress resistance, while an increase in 20E level induces its increase in sixday females both uninfected with the Wolbachia and infected with different bacterium strains (wMelCS, wMelPop, and wMel). However, the intensity of response differs: a decrease in the survival with an increase in JH level and its increase with an increase in 20E level are more pronounced in females infected with pathogenic wMelPop strain and less pronounced in females infected with the wMelCS genotype than in uninfected females and females infected with the wMel genotype. Data obtained suggest that the wMelCS genotype induces a decrease and wMelPop induces an increase in the level of stress hormone (dopamine), since previously we demonstrated that an increase in the JH level in mature females increases the dopamine level, an increase in the 20E level decreases it, and an increase/decrease in the dopamine level, in turn, leads to a decrease/increase of the Drosophila female resistance to heat stress. 相似文献