Alternative Transmission Patterns in Independently Acquired Nutritional Cosymbionts of Dictyopharidae Planthoppers.

Sap-sucking hemipterans host specialized, heritable microorganisms that supplement their diet with essential nutrients. These microbes show unusual features that provide a unique perspective on the coevolution of host-symbiont systems but are still poorly understood. Here, we combine microscopy with high-throughput sequencing to revisit 80-year-old reports on the diversity of symbiont transmission modes in a broadly distributed planthopper family, Dictyopharidae. We show that in seven species examined, the ancestral nutritional symbionts Sulcia and Vidania producing essential amino acids are complemented by co-primary symbionts, either Arsenophonus or Sodalis, acquired several times independently by different host lineages and contributing to the biosynthesis of B vitamins. These symbionts reside within separate bacteriomes within the abdominal cavity, although in females Vidania also occupies bacteriocytes in the rectal organ. Notably, the symbionts are transovarially transmitted from mothers to offspring in two alternative ways. In most examined species, all nutritional symbionts simultaneously infect the posterior end of the full-grown oocytes and next gather in their perivitelline space. In contrast, in other species, Sodalis colonizes the cytoplasm of the anterior pole of young oocytes, forming a cluster separate from the "symbiont ball" formed by late-invading Sulcia and Vidania. Our results show how newly arriving microbes may utilize different strategies to establish long-term heritable symbiosis. IMPORTANCE Sup-sucking hemipterans host ancient heritable microorganisms that supplement their unbalanced diet with essential nutrients and have repeatedly been complemented or replaced by other microorganisms. These symbionts need to be reliably transmitted to subsequent generations through the reproductive system, and often they end up using the same route as the most ancient ones. We show for the first time that in a single family of planthoppers, the complementing symbionts that have established infections independently utilize different transmission strategies, one of them novel, with the transmission of different microbes separated spatially and temporally. These data show how newly arriving microbes may utilize different strategies to establish long-term heritable symbioses.

Description of an Australian endemic species of Trioza (Hemiptera: Triozidae) pest of the endemic tea tree, Melaleuca alternifolia (Myrtaceae).

Psyllids, also known as jumping plant lice, are phloem feeding Hemiptera that often show a strict species-specific relationship with their host plants. When psyllid-plant associations involve economically important crops, this may lead to the recognition of a psyllid species as an agricultural or horticultural pest. The Australian endemic tea tree, Melaleuca alternifolia (Maiden & Betche) Cheel., has been used for more than a century to extract essential oils and, long before that, as a traditional medicine by Indigenous Australian people. Recently, a triozid species has been found to damage the new growth of tea trees both in Queensland and New South Wales, raising interest around this previously undocumented pest. Furthermore, adults of the same species were also collected from Citrus plantations, leading to potential false-positive records of the exotic pest Trioza erytreae (Del Guercio 1918), the African Citrus psyllid. Here we describe for the first time Trioza melaleucae Martoni sp. nov. providing information on its distribution, host plant associations and phylogenetic relationships to other Trioza species. This work enables both morphological and molecular identification of this new species, allowing it to be recognized and distinguished for the first time from exotic pests as well as other Australian native psyllids. Furthermore, the haplotype network analysis presented here suggests a close relationship between Trioza melaleucae and the other Myrtaceae-feeding Trioza spp. from Australia, New Zealand, and Taiwan.

Arthropod entombment in weathering-formed opal: new horizons for recording life in rocks.

Animal fossils preserved in various geological materials, such as limestone, claystone, or amber, provide detailed information on extinct species that is indispensable for retracing the evolution of terrestrial life. Here, we present the first record of an animal fossil preserved in opal formed by weathering with such high-resolution details that even individual cuticle hairs are observed. The fossil consists of the exoskeleton of a nymphal insect belonging to the order Hemiptera and either the family Tettigarctidae or the Cicadidae. This identification is based on anatomical details such as the tibial and femoral morphology of the forelegs. The exoskeleton of the insect was primarily zeolitized during the alteration of the host rocks and later sealed in opal deposited by silica-rich fluids derived from the continental weathering of the volcanic host rocks. Organic matter is preserved in the form of amorphous carbon. This finding makes opal formed by rocks weathering a new, complementary source of animal fossils, offering new prospects for the search for ancient life in the early history of Earth and possibly other terrestrial planets such as Mars, where weathering-formed opal occurs.

Molecular and Morphological Identifications Reveal Species Composition of Lygus (Hemiptera: Miridae) Bugs in Potatoes Fields in the Lower Columbia Basin of the United States.

Lygus bugs are highly polyphagous insect pests. In recent years, Lygus bugs have become more conspicuous on potato, Solanum tuberosum L., fields in the Pacific Northwest, particularly in the Lower Columbia Basin. There are concerns that direct feeding damage or potential pathogen transmission can reduce yield. Lygus species on potatoes in the region are collectively identified as 'Lygus bugs'. Overlapping physical traits and the fact that the same species exhibit morphological variations across a geographic range makes it difficult to identify Lygus to species level. Thus, in this study we used DNA barcodes in combination with morphological characters to identify Lygus species on potatoes. Three species were identified in the Lower Columbia Basin: Lygus hesperus (Knight) and Lygus elisus L. were the most common, whereas Lygus keltoni L. was the least common. Interspecific genetic distances among Lygus species were relatively low, ranging from 0.013 to 0.004. Neighbor-joining (NJ) tree clustered L. hesperus and L. elisus into two major clades, with L. keltoni forming a subclade within L. hesperus clade. Statistical parsimony analysis corroborated findings from phylogenetic analysis with L. keltoni and L. hesperus sharing one haplotype. Our study demonstrates the utility of integrating morphology and molecular markers in identifying morphologically similar species such as Lygus bugs. The study also serves as a fundamental step in contributing to developing suitable management strategies against Lygus bugs on potato.

Host-location behavior of the tea green leafhopper Empoasca vitis Göthe (Hemiptera: Cicadellidae): olfactory and visual effects on their orientation.

The tea green leafhopper, Empoasca vitis Göthe, is one of the most serious pests in tea growing areas. This study investigated the roles played by olfaction and vision in host orientation behavior. The compound eye of E. vitis was found to be a photopic eye; few olfactory sensilla were found on the antennae, while abundant gustatory sensilla were recorded on the mouthparts. Three opsin genes (EV_LWop, EV_UVop, EV_Bop) were isolated and found to be mainly expressed in the compound eye compared with other parts of the body. Immunolocalization indicated that the opsins mainly located in the different regions of rhabdom. The transcription levels of EV_LWop, EV_Bop and EV_UVop were reduced by 77.3, 70.0 and 40.0%, respectively, by RNA interference induced by being fed a special RNA-rich diet for 6 days. The rate of tropism to host color was effectively impaired by 67.6 and 29.5% in the dsEV_LWop and dsEV_Bop treatment groups, but there was no significant change in the dsEV_UVop group. The determination of the cause of the tropism indicated that odors from the host over long distances were unable to attract E. vitis and were only detected when the insects were close to the host. The developed compound eye of E. vitis plays a leading role in host location, and the long-wavelength opsin significantly affects the tropism to host color; the lack of olfactory sensilla results in long-distance odors not being able to be detected until the insect is near to the host-plant. The understanding of these behavioral mechanisms, especially the importance of opsin genes is expected to be useful for pest management.

The potato pest Russelliana solanicola Tuthill (Hemiptera: Psylloidea): taxonomy and host-plant patterns.

The Neotropical jumping plant-louse Russelliana solanicola Tuthill is a potato pest and a probable vector of plant pathogens. Populations morphologically similar to those found on potatoes have been collected on plants of at least ten different families, four of which have been confirmed as hosts by the presence of immatures. This suggests that R. solanicola is either a single polyphagous species or a complex of closely related, monophagous species (host races/cryptic species). Results of our analyses of multiple morphometric characters show for both sexes a grouping of the populations of R. solanicola and a clear separation of the latter from other Russelliana species. On the other hand, within R. solanicola, there is an overlap of populations from different host-plants as well as from different geographical regions. The results of the present study strongly suggest that R. solanicola is a single, polyphagous species and the known distribution indicates that it is native to the Andes. It is likely that R. solanicola has been introduced into eastern Argentina, Brazil and Uruguay. The polyphagy together with the ability to disperse and transmit plant pathogens potentially make this species an economically important pest of potato and other crop species.

Clarification of the Identity of the Tea Green Leafhopper Based on Morphological Comparison between Chinese and Japanese Specimens.

Tea green leafhopper is one of the most dominant pests in major tea production regions of East Asia. This species has been variously identified as Empoasca vitis (Goëthe), Jacobiasca formosana (Paoli) and Empoasca onukii Matsuda in Mainland China, Taiwan and Japan, respectively. Recent study of DNA sequence data suggested that treatment of this pest as different species in these three adjacent regions is incorrect and that they were a single species; but the correct scientific name for the species has remained unclear. Consistent with the prior molecular evidence, morphological study shows that the male genital characters of Chinese specimens are the same as those of specimens from Japan, so the correct scientific name of tea green leafhopper in China is Empoasca (Matsumurasca) onukii Matsuda.

[Comparative analysis of main agronomic traits and interrelationships in cultivation provenances of Pesudostellaria heterophylla from Guizhou province].

OBJECTIVE: To provide guidance for selection and breeding of Pesudostellaria heterophylla, agronomic traits of 3 mainly cultivated form of P. heterophylla were observed and compared in Guizhou shibing. METHOD: Thirteen agronomic traits of P. heterophylla from 3 cultivation form were measured and the traits were analyzed using multiple comparison, correlation analysis, multiple stepwise regression analysis and path analysis. RESULT: The results showed that agronomic traits were different in 3 cultivation form, significant(P <0.05)or very significant correlated (P <0.01)among multiple agronomic traits, the width and the number of root, the first branch number, cleistogamous flowers, length and width of leaves, and the aboveground biomass were the main factors that affected the underground biomass, and the number of root, the aboveground biomass had a directly positive effect on the underground biomass. Meanwhile, whole length, length and width of leaves, cleistogamous flowers etc. had direct or indirect effect on the underground biomass. CONCLUSION: Aboveground biomass would be as the best indirect selection traits on breeding high yield of P. heterophylla, the first branch number, width of leaves and cleistogamous flowers world be as a better auxiliary index on breeding high variety of P. heterophylla.

Potential economic pests of solanaceous crops: a new species of Solanum-feeding psyllid from Australia and first record from New Zealand of Acizzia solanicola (Hemiptera: Psyllidae).

Acizzia credoensis sp. n. is described from a single population on the native plant, Solanum lasiophyllum, from semi-arid Western Australia. The host range of Acizzia solanicola Kent & Taylor, initially recorded as damaging eggplant, S. melongena, in commercial crops and gardens and on wild tobacco bush, S. mauritianum in eastern Australia, is expanded to include the following Solanaceae: rock nightshade, S. petrophilum, cape gooseberry, Physalis peruviana, and an undetermined species of angel's trumpet Brugmansia and Datura. New Zealand specimens of A. solanicola collected in early 2012 from S. mauritianum are the first record for this species from outside Australia, and possibly represent a very recent incursion. The potential for the solanaceous-inhabiting Psyllidae to vector Candidatus Liberibacter solanacearum, an economically important plant pathogen, on native Australian Solanaceae is discussed. The occurrence of A. credoensis and A. solanicola on native Australian Solanum supports the Australian origin for the solanaceous-inhabiting Acizzia psyllids.

Ocorrência de cochonilhas em espinheira-santa (Maytenus ilicifolia Mart. ex Reissek) / Occurrence of mealybugs in "espinheira-santa" (Maytenus ilicifolia Mart. ex Reissek)

Maytenus ilicifolia é uma espécie medicinal nativa do Brasil que vem sendo cultivada para atender a crescente demanda do mercado. Os fatores que interferem na produção, tal como a incidência de pragas e doenças, devem ser estudados para garantir o incremento na produtividade. O objetivo deste trabalho foi registrar a ocorrência e a identificação de cochonilhas associadas a 15 acessos de espinheira-santa (Maytenus ilicifolia) do Banco Ativo de Germoplasma da Embrapa Clima Temperado e do Instituto Federal Sul-rio-grandense. Foi registrada a quantidade de plantas infestadas em cada acesso e identificado, em laboratório, as espécies de cochonilhas infestantes. O número de plantas infestadas variou entre os acessos. Foram identificadas as cochonilhas Ceroplastes sp. e Saissetia oleae, família Coccidae. Dos 10 acessos infestados, 23 (11,3%) plantas apresentaram infestação com Ceroplastes sp. e, apenas uma (0,5%), com Saissetia oleae. O acesso 133 mostrou a maior incidência de Ceroplastes sp. (33,3%), seguido do acesso 130 (25,0%). O acesso 123 foi o que apresentou menor quantidade de plantas infestadas (4,8%). Saissetia oleae ocorreu em apenas uma planta, pertencente ao acesso 136 (5,6%).

Maytenus ilicifolia is a medicinal species native to Brazil which has been cultivated to meet the growing market demand. Factors that interfere with the production, such as the incidence of pests and diseases, should be studied to ensure increased productivity. The aim of this study was to record the occurrence and the identification of mealybugs associated with 15 "espinheira-santa" (Maytenus ilicifolia) accessions from the Active Germplasm Bank of "Embrapa Clima Temperado" and "Instituto Federal Sul-rio-grandense". The quantity of infested plants in each accession was recorded and the species of infested mealybugs were identified in the laboratory. The number of infested plants varied among accessions. The identified mealybugs were Ceroplastes sp. and Saissetia oleae, family Coccidae. Of 10 infested accessions, 23 plants (11.3%) showed infestation with Ceroplastes sp., and only one (0.5%) with Saissetia oleae. Accession 133 showed the highest incidence of Ceroplastes sp. (33.3%), followed by accession 130 (25.0%). Accession 123 had the least amount of infested plants (4.8%). Saissetia oleae occurred in only one plant, belonging to accession 136 (5.6%).

Identification and phenology of Hyalesthes obsoletus (Hemiptera: Auchenorrhyncha: Cixiidae) nymphal instars.

Urtica dioica and Convolvulus arvensis are the main host plants of Hyalesthes obsoletus and play an important role in the epidemiology of Bois noir of grapevines. The earliest survey, which was carried out to compare the phenology of nymphal instars on U. dioica and C. arvensis, had highlighted some problems in the identification of the instars. Therefore, the correct identification of nymphs to species and instar level became a preliminary aim of this research. Adults and nymphs attributable to H. obsoletus were collected during 2008-2010 in three flatland vineyard habitats of northern Italy on U. dioica, C. arvensis and Artemisia verlotorum. Nymphs and morphologically identified adults of H. obsoletus were submitted to molecular identification. Morphometric and morphological studies were carried out on nymphs collected in the field or obtained in laboratory rearings. Molecular methods not only confirmed the identity of adults, but also allowed the assignment of the nymphs to this species. Morphometric and morphological characteristics (e.g. body and head-thoracic lengths, number of thoracic pits) showed the existence of five nymphal instars. Morphometric differences between newly hatched and older first-instar nymphs were observed. A key to distinguish the five instars was proposed. Evident differences between H. obsoletus nymphs studied here and elsewhere were identified. According to differences in adult-flight period, an earlier phenology of nymphs on C. arvensis than on U. dioica was observed. In particular, the typical overwintering instar was the second on U. dioica and the third on C. arvensis.

Transporters involved in glucose and water absorption in the Dysdercus peruvianus (Hemiptera: Pyrrhocoridae) anterior midgut.

Little is known about insect intestinal sugar absorption, in spite of the recent findings, and even less has been published regarding water absorption. The aim of this study was to shed light on putative transporters of water and glucose in the insect midgut. Glucose and water absorptions by the anterior ventriculus of Dysdercus peruvianus midgut were determined by feeding the insects with a glucose and a non-absorbable dye solution, followed by periodical dissection of insects and analysis of ventricular contents. Glucose absorption decreases glucose/dye ratios and water absorption increases dye concentrations. Water and glucose transports are activated (water 50%, glucose 33%) by 50 mM K(2)SO(4) and are inhibited (water 46%, glucose 82%) by 0.2 mM phloretin, the inhibitor of the facilitative hexose transporter (GLUT) or are inhibited (water 45%, glucose 35%) by 0.1 mM phlorizin, the inhibitor of the Na(+)-glucose cotransporter (SGLT). The results also showed that the putative SGLT transports about two times more water relative to glucose than the putative GLUT. These results mean that D. peruvianus uses a GLUT-like transporter and an SGLT-like transporter (with K(+) instead of Na(+)) to absorb dietary glucose and water. A cDNA library from D. peruvianus midgut was screened and we found one sequence homologous to GLUT1, named DpGLUT, and another to a sodium/solute symporter, named DpSGLT. Semi-quantitative RT-PCR studies revealed that DpGLUT and DpSGLTs mRNA were expressed in the anterior midgut, where glucose and water are absorbed, but not in fat body, salivary gland and Malpighian tubules. This is the first report showing the involvement of putative GLUT and SGLT in both water and glucose midgut absorption in insects.