Biology subjects

Soroker, V.

Publications and source records attributed to Soroker, V..

5 recordsLinked to original sources

bioRxiv2025

The effect of two distinct viral-enriched inocula on the immune response and chemical cues in honey bee pupae

The combination of Varroa destructor (Varroa) and the viruses it vectors is a major driver of honey bee (Apis mellifera) colony losses. Hygienic behavior and individual immunity enable bees to cope with some pests and parasites. Hygienic response of adult bees is driven by olfactory cues emanating from diseased brood. In this study, we tested the effect of viral inoculation on the chemical profile and immune response of pupae, independently of Varroa. We injected pupae with various doses of an enriched inocula of either a deformed wing virus (DWV) B-A recombinant or Israeli acute paralysis virus (IAPV) and followed their development and survival for five days. At the end of the five-day period, volatile profiles, viral loads, and expression of seven immune genes were assessed. Both IAPV and the DWV loads increased to equivalent high levels irrespective of the initial dose applied. Notably, greater rates of mortality (60% loss) were observed with the highest IAPV dose when compared to the lowest IAPV dose (15% loss). The DWV inoculum, caused limited mortality but nonetheless inhibited pupae development. The IAPV injected pupae showed evidence of a dose dependent DWV amplification from either a DWV variant in the original IAPV inoculum or from an endogenous source of DWV in the pupae themselves. IAPV-injected pupae had lower expression of immune genes than DWV-injected pupae, suggesting IAPV inhibits the pupae immune response. Overall, among the seven tested immune genes six were upregulated with only vago downregulated, suggesting inhibition of the RNAi pathway following infection. Chemical cues of mock and untreated pupae were similar, but notably different from the virus-injected pupae for both inocula. Our findings show that Varroa-independent virus inoculated pupae produce unique virus-specific chemical cues; the ultimate consequence of such a change might lead to virus specific bee behavioral responses. Authors summaryThis study investigated how two major honey bee viruses, Deformed Wing Virus (DWV) and Israeli Acute Paralysis Virus (IAPV), affect pupae independent of the Varroa mite, which typically spreads them. This study was conducted in the laboratory on incubated pupae isolated from the colony and injected with two viral preparations (inocula). We tested the impact after five-days incubation. The results show that both viruses reach high levels in pupae, though IAPV inoculum proved far more deadly (up to 60% mortality) and appeared to suppress the pupaes immune response, possibly even amplifying co-occurring DWV. While less lethal, the DWV inoculum still inhibited normal development. Interestigly, the virus-infected pupae produced distinct, virus-specific chemical cues--unique volatile profiles different from healthy controls. Since adult honey bees use olfactory cues to detect and remove diseased brood (hygienic behavior), these findings suggest that the viruses themselves generate the "scent of sickness," which could trigger colony-wide behavioral responses and offer a vital target for enhancing the bees natural defenses against these major drivers of colony loss. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=110 SRC="FIGDIR/small/683288v1_ufig1.gif" ALT="Figure 1"> View larger version (30K): org.highwire.dtl.DTLVardef@18e6203org.highwire.dtl.DTLVardef@c4b6d5org.highwire.dtl.DTLVardef@bf6499org.highwire.dtl.DTLVardef@165b9d1_HPS_FORMAT_FIGEXP M_FIG C_FIG

pathology↗

bioRxiv2024

Managed honey bee colony losses and causes during the active beekeeping season 2022/2023 in nine Sub-Saharan African countries

This study reports for the first-time managed honey bee colony loss rates and associated risk factors during the active beekeeping season 2022/2023 in nine Sub-Saharan African countries, namely Kenya, Ethiopia, Rwanda, Uganda, Benin, Liberia, Nigeria, Cameroon and Democratic Republic of the Congo. The sustainability of bee swarm catches as a main honey bee colony source tool for operation expansion by African beekeepers was also evaluated in Kenya and Ethiopia. In this survey, the 1,786 interviewed beekeepers across these countries collectively managing 41,761 colonies registered an overall loss rate of 21.3%, which varied significantly among countries (from 9.7 to 45.3%) and hive types (from 10.6% in hives with movable frames to 17.9% in frameless hives). The perceived causes of losses in order of significance were issues beyond the beekeepers control (mainly theft, drought, and bushfire), absconding and pests (mainly wax moth, small and large hive beetles, ants and Varroa destructor mite), but this pattern varied greatly across countries. Among the management practices and characteristics, migratory operations and professional beekeepers experienced lower losses than stationary operations and semi-professionals and hobby beekeepers. Insights into the number of bee swarms caught revealed significant decreases in swarm availability over the past three years in Kenya. The opposite situation was observed in some regions of Ethiopia. These trends require further investigation. Overall, this comprehensive survey sheds light on the complexities and challenges beekeepers faced in Sub-Saharan Africa, pointing to the need for targeted interventions and sustained research to support the resilience and growth of the apicultural sector.

zoology↗

bioRxiv2022

Identification of chemo-sensory genes from antennae of female banana pseudostem weevil, Odoiporous longicollis by transcriptomics approach

In the present study, the female O. longicollis antennal transcriptome was constructed by Illumina Hiseq 2500 sequencing, with the aim of discovering olfaction-related genes. Totally 12, 411 unigenes were identified from the transcriptome assembly and the putative genes functions were annotated using gene ontology tools. We identified 46 putative chemosensory unigenes likely essential for insect olfaction including 19 odorant binding proteins, 3 Niemann-Pick type C (NPC) protein, 6 odorant receptors, 15 ionotropic receptors, and 3 sensory neuron membrane proteins. The key function of these chemosensory genes in the antennae are discussed. Phylogenetic analysis of NPC revealed that the identified proteins had a close relationship with Coleopterans than other insects. This is the first ever report on identification of olfactory genes from O. longicollis which may provide new leads for control of this major pest.

molecular biology↗

bioRxiv2021

The payoffs and tradeoffs of hygienic behavior: A large-scale field study on a local population of honey bees

Honey bees (Apis mellifera) are exposed to a variety of risk factors, but the ectoparasitic mite Varroa destructor and its associated viruses are considered to be the most significant problem worldwide. It has been widely recognized that honey bee stocks resistant to the mites are an essential part of any sustainable long-term management of Varroa. The aim of this study was to evaluate the efficacy of hygienic behavior in a local population of honey bees in order to reduce Varroa infestation. A bi-directional selection for high and low rates of hygienic behavior was carried out in Israel using either queen artificially inseminated or naturally mated. Colonies were screened for performance: population size, honey production, control of Varroa infestation, and the level of hygienic behavior. Furthermore, we examined the costs and benefits of selection using measurements of colony performance. Either way, selected lines should be tested for trade-offs and benefits to ensure their productivity. The selection process revealed that the trait is heritable. Maternal phenotype has a significant effect on Varroa load, as colonies founded by hygienic daughter queens showed a significantly lower parasite load. No major trade-offs were found between the rate of hygienic behavior, honey yield, and population size. Measuring the direct benefits of hygienic behavior through colony performance suggests that breeding for this trait makes bees more resistant to Varroa destructor. These results are promising for our successful local bee breeding programs in a Mediterranean climate.

pathology↗

bioRxiv2021

Males perceive honest information from female released sex pheromone in a moth

There is accumulating evidence that male insects advertise their quality to conspecific females through pheromones. However, most studies of female released sex pheromone assume information transfer regarding merely the species of the female and her mating status. We show that more and precise information is conveyed through the female sex pheromone, positioning it as an honest sexual trait. We demonstrate that females in bad physical conditions (small, starved or old) lay significantly fewer eggs than females in good conditions (large, fed or young). The ratio of the sex pheromone blend in gland extracts of female pink bollworm moths accurately describes the female phenotypic condition whereas the pheromone amount in the glands fails to provide an honest signal of quality. Moreover, males use the female released pheromone blend to choose their mates and approach females that signal higher reproductive potential. In addition, surrogating the female effect, using synthetic pheromone blend that represents that of higher quality females (0.6:0.4 ZZ:ZE) more males were attracted to this blend than to the blend representing the population mean (0.5:0.5 ZZ:ZE). Both, female advertisement for males and the male choosiness, suggest that pheromones have evolved as sexual traits under directional, sexual selection.

evolutionary biology↗