Alleviation of arsenic-induced neurobehavioral defects with selenium in the larvae of Zaprionus indianus.

Selenium is an essential antioxidative micronutrient. This study was conducted to characterize the arsenic toxicity induced on the African fig fly, Zaprionus indianus, and its possible amelioration by selenium. We used computational tools and in vivo experiments to elucidate the mechanism of action of arsenic and selenium on Z. indianus larvae. We conducted experiments to study neurobehavioral parameters including learning and memory ability test and crawling and contraction assays. Our in silico study revealed twelve primary targets of arsenic trioxide. The gene ontology annotation of primary and secondary targets of arsenic trioxide revealed selenocysteine metabolic processes as one of the most reliable targets. To validate our in silico data, we analyzed the effect of arsenic trioxide on larvae of Z. indianus and tested the possible amelioration by sodium selenite supplementation. Our data demonstrated that the arsenic trioxide deteriorated the learning and memory ability of 2nd instar larvae of Z. indianus and such effect was reversed by sodium selenite supplementation. Furthermore, crawling and contraction assay done on 3rd instar larvae showed that there was reduction in both parameters upon arsenic trioxide exposure, which was restored with sodium selenite supplementation. Altogether, our computational and in vivo results strongly indicated that the neurobehavioral defects induced by arsenic trioxide on the larvae of Z. indianus can be successfully alleviated in the presence of sodium selenite.

Evaluation of control for the management of four pest species (Rhagoletis cerasi L., Ceratitis capitata Wied. (Diptera: Tephritidae), Drosophila suzukii (Matsumura) and Zaprionus indianus (Gupta) (Diptera: Drosophilidae)) in organic cherry-growing area.

BACKGROUND: In recent years, the fruit flies Rhagoletis cerasi L., Ceratitis capitata Wied. (Diptera: Tephritidae), Drosophila suzukii (Matsumura) and Zaprionus indianus (Gupta) (Diptera: Drosophilidae) (Tephritidae and Drosophilidae) have become an increasingly serious problem for cherry production in Turkey, which ranks first among cherry-producing countries. Intensive chemical control of these pests is used and little information about alternative methods of control is available for these pests, especially in organic farming. The purpose of our study was to determine a new, cost-efficient and more ecofriendly method of pest control. The study was carried out during 2019-2020 at two different locations in Turkey: Adana-Pozanti (Alpu, 1070 m, and Belemedik, 700 m). RESULTS: This study investigated the effectiveness against fruit flies of netting covering trees, a mass capture technique and an insecticide suitable for use in organic agriculture (spinosad). A comparative insecticide (thiacloprid) was also applied. The methods performed quite differently from the control and were shown to be particularly effective against R. cerasi and D. suzukii. The most effective control method against the four pest species was the application of netting (100% effect). The other methods of control included in the experiment may also be useful in organic cherry cultivation. CONCLUSION: The methods presented here meet the requirements for conventional and organic production. Application of netting in particular can form the basis of organic production requirements for the management of fruit flies. It has been observed that fruits ripen a little later, and fruit monilia and aphid damage are less in trees protected by netting. This is a commercial advantage, especially for late maturing varieties, and additional studies are needed for these varieties. © 2022 Society of Chemical Industry.

Fuzzy AHP-based spatial distribution of fig tree cultivation in Zaprionus indianus infection risk for sustainable agriculture development.

The spatial distribution of fig trees infected by Zaprionus indianus (ZI) disease, an invasive pest, was analyzed as a control solution to determine the prone area of their growth and cultivation prevention in Southwest Iran. With this aim, the study presented the use of 9 suitability variables for fig tree cultivation mapping in 3 main steps: (i) pre-processing data of each input variable with fuzzy membership function, (ii) land suitability mapping (LSM) by using the pair-wise comparison matrix of analytical hierarchy process (AHP) method and Geographical Information System (GIS) technique, (iii) exclusion layers of Zaprionus indianus from the temperature data and growing degree days (GDD) (from April to October) with the support of inverse distance weighting (IDW) method. The results show that the central regions and parts of the east and northwest of the region (16%) are more suitable for fig cultivation. Compared to 7 growth periods, the insect is more active in the southern parts of the region than in the northern parts. Therefore, it is possible to cultivate figs with high yield in parts of the region where the land is suitable for growing this crop with the lowest activity of ZI. The overlay results show that the suitability distribution of fig cultivation in high and very high levels is mainly in the central regions (13,300 km2, 10%), parts of the east (5320 km2, 4%), and northwest (2660 km2, 2%) of the region. The proposed approach can be useful for management, planners, and local people in the development of agricultural production areas.

Distinctive features of Zaprionus indianus hemocyte differentiation and function revealed by transcriptomic analysis.

Background: Insects have specialized cell types that participate in the elimination of parasites, for instance, the lamellocytes of the broadly studied species Drosophila melanogaster. Other drosophilids, such as Drosophila ananassae and the invasive Zaprionus indianus, have multinucleated giant hemocytes, a syncytium of blood cells that participate in the encapsulation of the eggs or larvae of parasitoid wasps. These cells can be formed by the fusion of hemocytes in circulation or originate from the lymph gland. Their ultrastructure highly resembles that of the mammalian megakaryocytes. Methods: Morphological, protein expressional, and functional features of blood cells were revealed using epifluorescence and confocal microscopy. The respective hemocyte subpopulations were identified using monoclonal antibodies in indirect immunofluorescence assays. Fluorescein isothiocyanate (FITC)-labeled Escherichia coli bacteria were used in phagocytosis tests. Gene expression analysis was performed following mRNA sequencing of blood cells. Results: D. ananassae and Z. indianus encapsulate foreign particles with the involvement of multinucleated giant hemocytes and mount a highly efficient immune response against parasitoid wasps. Morphological, protein expressional, and functional assays of Z. indianus blood cells suggested that these cells could be derived from large plasmatocytes, a unique cell type developing specifically after parasitoid wasp infection. Transcriptomic analysis of blood cells, isolated from naïve and wasp-infected Z. indianus larvae, revealed several differentially expressed genes involved in signal transduction, cell movements, encapsulation of foreign targets, energy production, and melanization, suggesting their role in the anti-parasitoid response. A large number of genes that encode proteins associated with coagulation and wound healing, such as phenoloxidase activity factor-like proteins, fibrinogen-related proteins, lectins, and proteins involved in the differentiation and function of platelets, were constitutively expressed. The remarkable ultrastructural similarities between giant hemocytes and mammalian megakaryocytes, and presence of platelets, and giant cell-derived anucleated fragments at wound sites hint at the involvement of this cell subpopulation in wound healing processes, in addition to participation in the encapsulation reaction. Conclusion: Our observations provide insights into the broad repertoire of blood cell functions required for efficient defense reactions to maintain the homeostasis of the organism. The analysis of the differentiation and function of multinucleated giant hemocytes gives an insight into the diversification of the immune mechanisms.

Genomic signatures of admixture and selection are shared among populations of Zaprionus indianus across the western hemisphere.

Introduced species have become an increasingly common component of biological communities around the world. A central goal in invasion biology is therefore to identify the demographic and evolutionary factors that underlie successful introductions. Here we use whole genome sequences, collected from populations in the native and introduced range of the African fig fly, Zaprionus indianus, to quantify genetic relationships among them, identify potential sources of the introductions, and test for selection at different spatial scales. We find that geographically widespread populations in the western hemisphere are genetically more similar to each other than to lineages sampled across Africa, and that these populations share a mixture of alleles derived from differentiated African lineages. Using patterns of allele-sharing and demographic modelling we show that Z. indinaus have undergone a single expansion across the western hemisphere with admixture between African lineages predating this expansion. We also find support for selection that is shared across populations in the western hemisphere, and in some cases, with a subset of African populations. This suggests either that parallel selection has acted across a large part of Z. indianus's introduced range; or, more parsimoniously, that Z. indianus has experienced selection early on during (or prior-to) its expansion into the western hemisphere. We suggest that the range expansion of Z. indianus has been facilitated by admixture and selection, and that management of this invasion could focus on minimizing future admixture by controlling the movement of individuals within this region rather than between the western and eastern hemisphere.

Effect of Visual Cues and a Fermentation-Based Attractant Blend on Trap Catch of Two Invasive Drosophila Flies in Berry Crops in Mexico.

Drosophila suzukii (Matsumura) and Zaprionus indianus (Gupta) (Diptera: Drosophilidae) are invasive pests of economic importance worldwide. This study was undertaken as a first step to investigate the interaction between visual and chemical cues on the captures of D. suzukii and Z. indianus under field conditions. Specifically, we evaluated the effect of color cardboards and their combinations on the capture of these drosophilids by attractant-baited multihole traps in blackberry and blueberry crops. Color had a significant effect on the captures of D. suzukii and Z. indianus by attractant-baited traps in both crops. Overall, attractant-baited traps with yellow and yellow + green cards captured the highest number of flies compared to attractant-baited traps using cards of other colors or without cards. Multihole traps without attractant and color cardboards caught very few flies of both species. In general, more females than male D. suzukii were captured, but no sexual differences were found in the captures of Z. indianus. The results obtained will be useful for the development of a monitoring or mass trapping system for the management of D. suzukii and Z. indianuspopulations in Mexico.

Comparison of overwintering survival and fertility of Zaprionus indianus (Diptera: Drosophilidae) flies from native and invaded ranges.

Zaprionus indianus is a fly species native to the Afrotropical biogeographic region that invaded the South American continent 20 years ago. Its southernmost record is 34°S in areas with temperate climates with cold winters. To better understand its invasion biology, we investigated physiological responses to winter-like abiotic conditions that may be relevant in Z. indianus geographic expansion. We characterized Z. indianus females reproductive traits (ovarian maturation and fertility) and survival in response to cold treatments with summer-like and winter-like photoperiods. We also compared these traits between native (Yokadouma, Africa) and invasive (Yuto, South America) range wild-derived flies. We showed that Z. indianus females have the ability to arrest ovarian maturation and maintain fertility following recovery from cold stress. The critical temperature for ovarian maturation of this species was estimated at c. 13 °C, an intermediate value between those of tropical and temperate drosophilid species. Wild-derived females from Yuto responded to winter-like photoperiod by slowing down ovarian maturation at low but permissive temperatures of 14 °C and 16 °C and also delayed the start of oviposition after cold treatment. Yuto flies also survived better and recovered 20% faster from chill coma than flies from Yokadouma. These results are consistent with a scenario of local adaptations or phenotypic plasticity in the invaded range, and suggest that photoperiod could act as modulator of ovarian arrest. Conversely, the fact that native range flies showed higher fertility after cold recovery than females from invaded range is not indicative of local adaptation. All in all, our findings report a set of physiological responses that would enable Z. indianus expansion to temperate and cold areas, but also results that are compatible with a limitation to the invasion process.

Contrasting levels of genotype by environment interaction for life history and morphological traits in invasive populations of Zaprionus indianus (Diptera: Drosophilidae).

It has been demonstrated that phenotypic plasticity and genotype by environment interaction are important for coping with new and heterogeneous environments during invasions. Zaprionus indianus Gupta (Diptera: Drosophilidae) is an Afrotropical invasive fly species introduced to the South American continent in 1999. This species is generalist and polyphagous, since it develops and feeds in several different fruit species. These characteristics of Z. indianus suggest that phenotypic plasticity and genotype by environment interaction may be important in this species invasion process. In this sense, our aim was to investigate the role of genetic variation for phenotypic plasticity (genotype by environment interaction) in Z. indianus invasion of the South American continent. Specifically, we quantified quantitative genetic variation and genotype by environment interactions of morphological and life history traits in different developmental environments, that is, host fruits. This was done in different populations in the invasive range of Z. indianus in Argentina. Results showed that Z. indianus populations have considerable amounts of quantitative genetic variation. Also, genotype by environment interactions was detected for the different traits analyzed in response to the different developmental environments. Interestingly, the amounts and patterns of these parameters differed between populations. We interpreted these results as the existence of differences in evolutionary potential between populations that have an important role in the short- and long-term success of the Z. indianus invasion process.

Cellular Immune Response Involving Multinucleated Giant Hemocytes with Two-Step Genome Amplification in the Drosophilid Zaprionus indianus.

Previously, a novel cell type, the multinucleated giant hemocyte (MGH) was identified in the ananassae subgroup of Drosophilidae. These cells share several features with mammalian multinucleated giant cells, a syncytium of macrophages formed during granulomatous inflammation. We were able to show that MGHs also differentiate in Zaprionus indianus, an invasive species belonging to the vittiger subgroup of the family, highly resistant to a large number of parasitoid wasp species. We have classified the MGHs of Z. indianusas giant hemocytes belonging to a class of cells which also include elongated blood cells carrying a single nucleus and anuclear structures. They are involved in encapsulating parasites, originate from the lymph gland, can develop by cell fusion, and generally carry many nuclei, while possessing an elaborated system of canals and sinuses, resulting in a spongiform appearance. Their nuclei are all transcriptionally active and show accretion of genetic material. Multinucleation and accumulation of the genetic material in the giant hemocytes represents a two-stage amplification of the genome, while their spongy ultrastructure substantially increases the contact surface with the extracellular space. These features may furnish the giant hemocytes with a considerable metabolic advantage, hence contributing to the mechanism of the effective immune response.

Cross-tolerance effects due to adult heat hardening, desiccation and starvation acclimation of tropical drosophilid-Zaprionus indianus.

Some insect taxa from polar or temperate habitats have shown cross-tolerance for multiple stressors but tropical insect taxa have received less attention. Accordingly, we considered adult flies of a tropical drosophilid-Zaprionus indianus for testing direct as well as cross-tolerance effects of rapid heat hardening (HH), desiccation acclimation (DA) and starvation acclimation (SA) after rearing under warmer and drier season specific simulated conditions. We observed significant direct acclimation effects of HH, DA and SA; and four cases of cross-tolerance effects but no cross-tolerance between desiccation and starvation. Cross-tolerance due to heat hardening on desiccation showed 20% higher effect than its reciprocal effect. There is greater reduction of water loss in heat hardened flies (due to increase in amount of cuticular lipids) as compared with desiccation acclimated flies. However, cross-tolerance effect of SA on heat knockdown was two times higher than its reciprocal. Heat hardened and desiccation acclimated adult flies showed substantial increase in the level of trehalose and proline while body lipids increased due to heat hardening or starvation acclimation. However, maximum increase in energy metabolites was stressor specific i.e. trehalose due to DA; proline due to HH and total body lipids due to SA. Rapid changes in energy metabolites due to heat hardening seem compensatory for possible depletion of trehalose and proline due to desiccation stress; and body lipids due to starvation stress. Thus, observed cross-tolerance effects in Z. indianus represent physiological changes to cope with multiple stressors related to warmer and drier subtropical habitats.

Whole genome sequence resource of Indian Zaprionus indianus.

This article documents the whole genome sequence information of the Indian Zaprionus indianus, a member of the fruit fly family Drosophilidae. The sequences were generated on an Illumina platform and reads and whole genome sequence submitted to NCBI to the SRA and BioProject databases, respectively. This is the first Indian Z. indianus whole genome (draft) submitted to the sequence repository with SRA reads. The details of methodology, assembly statistics and functional annotation are presented in this work.

Structure and ultrastructure of spermatozoon in six species of Drosophilidae (Diptera).

The Drosophilidae family is formed by Brachycera Diptera distributed widely across different regions of the planet. It is composed of about 4000 species, 304 of which are found in Brazil. The objective of this work was to characterize morphologically the structure of the male internal reproductive apparatus and the ultrastructure of the spermatozoon in four Neotropical (Drosophila cardini, D. mercatorum, D. nebulosa and D. sturtevanti) and two invasive (D. simulans and Zaprionus indianus) species of drosophilids. The structural aspect of the internal reproductive apparatus corresponds with that described for other drosophilids; however, there are differences in the size and coloration of the structures, such as the testes, in each species analyzed. The spermatozoon of these species was seen to be long and fine, presenting morphological variation. The ultrastructure of the spermatozoon revealed that the morphological pattern is similar to that found in the majority of insects. The head region presents a nucleus with condensed chromatin and the acrosome positioned laterally to the nucleus. In the tail region, the axoneme presents the 9+9+2 pattern commonly described for other species of Diptera. The species presented differences regarding the shape and size of the mitochondrial derivatives. Cytochemical analysis using EPTA also revealed differences in terms of the location of the basic proteins in the mitochondrial derivates. The results obtained contribute to expanding the database for the Drosophilidae family, providing information that may contribute to intra- and inter-specific identification and supplying phylogenetic analyses.

Effects of saturation deficit on desiccation resistance and water balance in seasonal populations of the tropical drosophilid Zaprionus indianus.

Seasonally varying populations of ectothermic insect taxa from a given locality are expected to cope with simultaneous changes in temperature and humidity through phenotypic plasticity. Accordingly, we investigated the effect of saturation deficit on resistance to desiccation in wild-caught flies from four seasons (spring, summer, rainy and autumn) and corresponding flies reared in the laboratory under season-specific simulated temperature and humidity growth conditions. Flies raised under summer conditions showed approximately three times higher desiccation resistance and increased levels of cuticular lipids compared with flies raised in rainy season conditions. In contrast, intermediate trends were observed for water balance-related traits in flies reared under spring or autumn conditions but trait values overlapped across these two seasons. Furthermore, a threefold difference in saturation deficit (an index of evaporative water loss due to a combined thermal and humidity effect) between summer (27.5 mB) and rainy (8.5 mB) seasons was associated with twofold differences in the rate of water loss. Higher dehydration stress due to a high saturation deficit in summer is compensated by storage of higher levels of energy metabolite (trehalose) and cuticular lipids, and these traits correlated positively with desiccation resistance. In Z. indianus, the observed changes in desiccation-related traits due to plastic effects of simulated growth conditions correspond to similar changes exhibited by seasonal wild-caught flies. Our results show that developmental plastic effects under ecologically relevant thermal and humidity conditions can explain seasonal adaptations for water balance-related traits in Z. indianus and are likely to be associated with its invasive potential.

Insights into differential activity patterns of drosophilids under semi-natural conditions.

We showed recently that Drosophila ananassae, a closely related and sympatric species of the commonly studied fruitfly D. melanogaster, shows distinctly deviant patterns in circadian activity/rest rhythm from the latter under a variety of laboratory conditions. To examine whether such differences extend to more natural conditions where a variety of time cues and similar environmental pressures might force different species to adopt similar temporal patterns, we examined these two species under semi-natural conditions over a span of 1.5 years. Furthermore, we asked to what extent features of activity/rest rhythm of flies are conserved across species under changing environmental conditions encountered across seasons, and to do so, we studied two more drosophilid species. We found that while each species exhibits seasonality in activity patterns, this seasonality is marked by interesting inter-specific differences. Similar to laboratory studies, D. ananassae showed activity mostly during the day, while D. melanogaster and D. malerkotliana exhibited almost similar activity patterns across seasons, with predominantly two peaks of activity, one in the morning and another in the evening. Throughout the year, Zaprionus indianus displayed very low levels of activity compared with D. melanogaster, yet, compared with those seen in standard laboratory assays, this species exhibited more robust rhythms under semi-natural conditions. We hypothesise that different ecological factors may have influenced these species to adopt different temporal niches.

Spermatogenesis of Zaprionus indianus and Zaprionus sepsoides (Diptera, Drosophilidae): Cytochemical, structural and ultrastructural characterization.

Zaprionus indianus is a drosophilid native to the Afrotropical region that has colonized South America and exhibits a wide geographical distribution. In contrast, Z. sepsoides is restricted to certain African regions. The two species differ in the size of their testes, which are larger in Z. indianus than in Z. sepsoides. To better understand the biology and the degree of differentiation of these species, the current study evaluated spermatogenesis in males of different ages by conventional staining techniques and ultrastructural analysis. Spermatogenesis and the ultrastructure of spermatozoa were similar in the two species, and the diploid number was confirmed to be 2n = 12. A greater number of spermatozoa were observed in young Z. indianus (1-3 days old) compared to Z. sepsoides males, which showed a higher frequency of cells at the early stages of spermatogenesis. The head of the sperm was strongly marked by silver staining, lacto-acetic orcein and the Feulgen reaction; the P.A.S. reaction revealed glycogen granules in the testes of both species. Both species presented similar arrangement of microtubules (9+9+2), two mitochondrial derivatives of different size and 64 spermatozoa per bundle. Such similarity within the genus Zaprionus with other species of Drosophila, indicates that these structures are conserved in the family Drosophilidae. The differences observed the number and frequency of sperm cells in the early stages of spermatogenesis, between the young males of Z. indianus and Z. sepsoides, are features that may interfere with reproductive success and be related to the invasive potential of Z. indianus.

Scenario of the spread of the invasive species Zaprionus indianus Gupta, 1970 (Diptera, Drosophilidae) in Brazil.

Zaprionus indianus was first recorded in Brazil in 1999 and rapidly spread throughout the country. We have obtained data on esterase loci polymorphisms (Est2 and Est3), and analyzed them, using Landscape Shape Interpolation and the Monmonier Maximum Difference Algorithm to discover how regional invasion occurred. Hence, it was apparent that Z. indianus, after first arriving in São Paulo state, spread throughout the country, probably together with the transportation of commercial fruits by way of the two main Brazilian freeways, BR 153, to the south and the surrounding countryside, and the BR 116 along the coast and throughout the north-east.

Scenario of the spread of the invasive species Zaprionus indianus Gupta, 1970 (Diptera, Drosophilidae) in Brazil

Zaprionus indianus was first recorded in Brazil in 1999 and rapidly spread throughout the country. We have obtained data on esterase loci polymorphisms (Est2 and Est3), and analyzed them, using Landscape Shape Interpolation and the Monmonier Maximum Difference Algorithm to discover how regional invasion occurred. Hence, it was apparent that Z. indianus, after first arriving in São Paulo state, spread throughout the country, probably together with the transportation of commercial fruits by way of the two main Brazilian freeways, BR 153, to the south and the surrounding countryside, and the BR 116 along the coast and throughout the north-east.

Homology of polytene elements between Drosophila and Zaprionus determined by in situ hybridization in Zaprionus indianus

The drosophilid Zaprionus indianus due to its economical importance as an insect pest in Brazil deserves more investigation into its genetics. Its mitotic karyotype and a line-drawing map of its polytene chromosomes are already available. This paper presents a photomap of Z. indianus polytene chromosomes, which was used as the reference map for identification of sections marked by in situ hybridization with gene probes. Hybridization signals for Hsp70 and Hsr-omega were detected, respectively, in sections 34B and 32C of chromosome V of Z. indianus, which indicates its homology to the chromosomal arm 3R of Drosophila melanogaster and, therefore, to Muller's element E. The main signal for Hsp83 gene probe hybridization was in section 17C of Z. indianus chromosome III, suggesting its homology to arm 3L of D. melanogaster and to element D of Muller. The Ubi probe hybridized in sections 10C of chromosome II and 17A of chromosome III. Probably the 17A is the polyubiquitin locus, with homology to arm 3L of D. melanogaster and to the mullerian D element, as suggested also by Hsp83 gene location. The Br-C gene was mapped in section 1D, near the tip of the X chromosome, indicating its homology to the X chromosome of D. melanogaster and to mullerian element A. The Dpp gene probe hybridized mainly in the section 32A of chromosome V and, at lower frequencies to other sections, although no signal was observed as expected in the correspondent mullerian B element. This result led to the suggestion of a rearrangement including the Dpp locus in Z. indianus, the secondary signals possibly pointing to related genes of the TGF-beta family. In conclusion, the results indicate that chromosomes X, III, V of Z. indianus are respectively correspondents to elements A, D, and E of Muller. At least chromosome V of Z. indianus seems to share synteny with the 3R arm of D. melanogaster, as indicated by the relative positions of Hsp70 and Hsr-omega, although the Dpp gene indicates a disruption of synteny in its distal region.

DESICCATION AND STARVATION TOLERANCE OF ADULT DROSOPHILA: OPPOSITE LATITUDINAL CLINES IN NATURAL POPULATIONS OF THREE DIFFERENT SPECIES.

Desiccation and starvation tolerance were measured along latitudinal transects in three Drosophilid species (Drosophila ananassae, D. melanogaster, and Zaprionus indianus) of the Indian subcontinent. In each case, significant latitudinal clines were observed; desiccation tolerance increased with latitude while starvation tolerance decreased. Such field observations suggest that desiccation and starvation tolerance are fitness related traits that are independently selected in nature and genetically independent. It was, however, difficult to relate these genetic changes with precise climatic variables, except winter temperature. The overall negative correlation between the two traits, which was evidenced in natural populations, contrasts with a positive correlation generally observed in various laboratory selection experiments and that also seems to exist between different species. These observations point to the difficulty of interpreting correlations among fitness-related traits when different evolutionary levels are compared, and also different sets of data, that is, field versus laboratory studies.