Self-Recognition and Allorecognition Mechanisms Exert a Significant Influence on the Sex Allocation Patterns of the Pea Aphid.

The mechanism controlling sex allocation in the pea aphid, (Harris), remains a crucial yet unresolved issue in the field of evolutionary ecology. This study aims to assess the influence of the presence of both self and non-self clones, along with juvenile hormone III (JH III) titer, on the sex allocation of aphid offspring. To this end, red and green clones were utilized as experimental subjects, and the agar method was employed.

Interspecific recognition based on cuticular hydrocarbons mediates reproduction control in aphids.

The preset study tested whether an aphid species can control its reproduction by recognizing the presence and density of a rival species. Acyrthosiphon pisum and Megoura crassicauda often coexist on the same leguminous plant. We established clonal colonies from each species and mixed colonies with one A.

Taxonomic revision of the Tetraneura akinire species group (Insecta, Aphididae, Eriosomatinae), with description of a new species and a correction of a nomenclatural confusion.

Gall-forming aphid species Tetraneura nigriabdominalis and T. fusiformis and its closely related species are taxonomically revised. By referring to the original descriptions, the name T.

Self and non-self recognition affects clonal reproduction and competition in the pea aphid.

The spatial interaction of clonal organisms is an unsolved but crucial topic in evolutionary biology. We evaluated the interactions between aphid clones using a colour mutant (yellow) and an original (green) clone. Colonies founded by two aphids of the same clone and mixed colonies, founded by a green aphid and a yellow aphid, were set up to observe population growth for 15 days.

Liquid Marbles in Nature: Craft of Aphids for Survival.

Some aphids that live in the leaf galls of the host plant are known to fabricate liquid marbles consisting of honeydew and wax particles as an inner liquid and a stabilizer, respectively. In this study, the liquid marbles fabricated by the galling aphids, Eriosoma moriokense, were extensively characterized with respect to size and size distribution, shape, nanomorphology, liquid/solid weight ratio, and chemical compositions. The stereo microscopy studies confirmed that the liquid marbles have a near-spherical morphology and that the number-average diameter was 368 ± 152 μm, which is 1 order of magnitude smaller than the capillary length of the honeydew.

Effects of Radiation From Contaminated Soil and Moss in Fukushima on Embryogenesis and Egg Hatching of the Aphid Prociphilus oriens.

Radiation-contaminated soils are widespread around the Fukushima Daiichi Nuclear Power Plant, and such soils raise concerns over its harmful effect on soil-dwelling organisms. We evaluated the effects of contaminated soil and moss sampled in Fukushima on the embryogenesis and hatching of aphid eggs, along with the measurement of the egg exposure dose. Cs-137 concentration in soil and moss from Fukushima ranged from 2200 to 3300 Bq/g and from 64 to 105 Bq/g, respectively.

Transgenerational seasonal timer for suppression of sexual morph production in the pea aphid, Acyrthosiphon pisum.

Many aphid species switch reproductive modes seasonally, with the sexual generations appearing in autumn. Sexual generations are induced by short days. It has been reported that the appearance of sexual morphs is suppressed by a transgenerational factor (a seasonal timer) over several generations after hatching from overwintered eggs.

Cryptic diversity of the subfamily Calaphidinae (Hemiptera: Aphididae) revealed by comprehensive DNA barcoding.

Aphids are a species rich group comprising many important pests. However, species identification can be very difficult for aphids due to their morphological ambiguity. DNA barcoding has been widely adopted for rapid and reliable species identification as well as cryptic species detection.

Genetic Variability of the Invasive Species Metcalfa pruinosa (Hemiptera: Flatidae) in the Republic of Korea.

Metcalfa pruinosa (Say, 1830) (Hemiptera: Flatidae) has caused substantial agricultural damage since its recent introduction to the Republic of Korea; however, the source of this introduction is still unclear. To examine the genetic divergence and phylogenetic relationships among several populations of M. pruinosa from Korea and foreign countries, 251 COI sequences from 251 samples collected from Korea, France, Italy, Spain, Slovenia, and the United States were newly analyzed, together with seven published COI sequences from Canada.

A new species of Megoura (Hemiptera, Aphididae) from Japan.

A new species of the genus Megoura, M. lathyricola sp. n.

Morphological abnormalities in gall-forming aphids in a radiation-contaminated area near Fukushima Daiichi: selective impact of fallout?

To evaluate the impact of fallout from the Fukushima Daiichi Nuclear Power Plant accident on organisms, this study compared the morphology and viability of gall-forming aphids between the Fukushima population and control populations from noncontaminated areas. This study, in particular, focused on the morphology of first-instar gall formers derived from the first sexual reproduction after the accident. Of 164 first instars from Tetraneura sorini galls collected 32 km from Fukushima Daiichi in spring 2012, 13.

Taxonomic status of the Bemisia tabaci complex (Hemiptera: Aleyrodidae) and reassessment of the number of its constituent species.

Bemisia tabaci (Hemiptera: Aleyrodidae) is one of the most important insect pests in the world. In the present study, the taxonomic status of B. tabaci and the number of species composing the B.

Seasonal changes in the genetic structure of an aphid-ant mutualism as revealed using microsatellite analysis of the aphid Tuberculatus quercicola and the ant Formica yessensis.

The present study examined whether the mutualistic relationship between the aphid Tuberculatus quercicola (Matsumura) (Homoptera: Aphididae) and the attending ant Formica yessensis Forel (Hymenoptera: Formicidae) has had any mutual effects on the microgeographical genetic population structure of both partner species. The aphids and the attending ants were collected in June, August, and October 2004 from six trees of the Daimyo oak Quercus dentata Thunberg (Fagales: Fagaceae) and were genotyped using microsatellite loci. Significant genetic differentiation was detected among T.

Allelic and genotypic diversity in long-term asexual populations of the pea aphid, Acyrthosiphon pisum in comparison with sexual populations.

Many aphid species exhibit geographical variation in the mode of reproduction that ranges from cyclical parthenogenesis with a sexual phase to obligate parthenogenesis (asexual reproduction). Theoretical studies predict that organisms reproducing asexually should maintain higher allelic diversity per locus but lower genotypic diversity than organisms reproducing sexually. To corroborate this hypothesis, we evaluated genotypic and allelic diversities in the sexual and asexual populations of the pea aphid, Acyrthosiphon pisum (Harris).

Inbreeding depression, increased phenotypic variance, and a trade-off between gonads and appendages in selfed progeny of the aphid Prociphilus oriens.

Trade-offs are potentially common among two or more traits whose development is dependent on the same resources. To detect genetic trade-offs, the techniques of quantitative genetics, pedigree analyses, and selection experiments have been used. This study demonstrates genetically based trade-offs between gonads and appendages in hatched larvae of the aphid Prociphilus oriens by focusing on enlarged variance among the families of selfed progeny.

Experimental hybridisation between X0 and XY chromosome races in the grasshopper Podisma sapporensis Shir. (Orthoptera, Acrididae). I. Cytological analysis of embryos and F1 hybrids.

The results of experimental hybridisation between some chromosome subraces belonging to the X0 and XY chromosome races of the brachypterous grasshopper P. sapporensis are presented. Pre-zygotic reproductive isolation mechanisms in experimental pairs were not confirmed.

Ant attendance changes the sugar composition of the honeydew of the drepanosiphid aphid Tuberculatus quercicola.

Mutualistic interactions between aphids and ants are mediated by the honeydew produced by aphids. Previous work showed that when attended by the ant Formica yessensis, nymphs of the aphid Tuberculatus quercicola developed into significantly smaller adults with lower fecundity than when not ant-attended. This study tested the hypothesis that this cost of ant attendance arises through changes in the quality and quantity of honeydew.