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The insect chemosensory system plays an important role in many aspects of insects' behaviors necessary for their survival. Despite the complexity of this system, an increasing number of studies have begun to understand its structure and function in different insect species. Nonetheless, the chemosensory system in the orange spiny whitefly Aleurocanthus spiniferus , as one of the most destructive insect pests of citrus in tropical Asia, has not been investigated yet. In this study, the sensillum types, morphologies and distributions of the male and female antennae of A. spiniferus were characterized using scanning electron microscopy. In both sexes, six different sensilla types were observed: trichodea sensilla, chaetica sensilla, microtrichia sensilla, coeloconic sensilla, basiconic sensilla, and finger-like sensilla. Moreover, we identified a total of 48 chemosensory genes, including 5 odorant-binding proteins (OBPs), 12 chemosensory proteins (CSPs), 3 sensory neuron membrane proteins (SNMPs), 6 odorant receptors (ORs), 8 gustatory receptors (GRs), and 14 ionotropic receptors (IRs) using transcriptome data analysis. Tissue-specific transcriptome analysis of these genes showed predominantly expression in the head (including antennae), whereas CSPs were broadly expressed in both head (including the antennae) and body tissue of adult A. spiniferus. In addition, the expression profiling of selected chemosensory genes at different developmental stages was examined by quantitative real time-PCR which was mapped to the transcriptome. We found that the majority of these genes were highly expressed in adults, while AspiORco , AspiGR1 , AspiGR2 , and AspiIR4 genes were only detected in the pupal stage. Together, this study provides a basis for future chemosensory and genomic studies in A. spiniferus and closely related species. Furthermore, this study not only provides insights for further research on the molecular mechanisms of A. spiniferus -plant interactions but also provides extensive potential targets for pest control. [ABSTRACT FROM AUTHOR]

The insect chemosensory system plays an important role in many aspects of insects’ behaviors necessary for their survival. Despite the complexity of this system, an increasing number of studies have begun to understand its structure and function in different insect species. Nonetheless, the chemosensory system in the orange spiny whitefly Aleurocanthus spiniferus, as one of the most destructive insect pests of citrus in tropical Asia, has not been investigated yet. In this study, the sensillum types, morphologies and distributions of the male and female antennae of A. spiniferus were characterized using scanning electron microscopy. In both sexes, six different sensilla types were observed: trichodea sensilla, chaetica sensilla, microtrichia sensilla, coeloconic sensilla, basiconic sensilla, and finger-like sensilla. Moreover, we identified a total of 48 chemosensory genes, including 5 odorant-binding proteins (OBPs), 12 chemosensory proteins (CSPs), 3 sensory neuron membrane proteins (SNMPs), 6 odorant receptors (ORs), 8 gustatory receptors (GRs), and 14 ionotropic receptors (IRs) using transcriptome data analysis. Tissue-specific transcriptome analysis of these genes showed predominantly expression in the head (including antennae), whereas CSPs were broadly expressed in both head (including the antennae) and body tissue of adult A. spiniferus. In addition, the expression profiling of selected chemosensory genes at different developmental stages was examined by quantitative real time-PCR which was mapped to the transcriptome. We found that the majority of these genes were highly expressed in adults, while AspiORco, AspiGR1, AspiGR2, and AspiIR4 genes were only detected in the pupal stage. Together, this study provides a basis for future chemosensory and genomic studies in A. spiniferus and closely related species. Furthermore, this study not only provides insights for further research on the molecular mechanisms of A. spiniferus-plant interactions but also provides extensive potential targets for pest control.

The parasitoid Encarsia smithi comprises two phylogeneticgroups. Type I is a strain that was introduced from China in 1925 to controlthe orange spiny whitefly, Aleurocanthus spiniferus, in Japanese citrusorchards. The other strain, type II, was accidentally introduced andhas recently been found in tea fields infested with the tea spiny whitefly,A. camelliae. In this report, we describe our developed rearing methodfor successive generations of the two strains using A. spiniferus-infestedcitrus seedlings. In rearing experiments, we found these strains to havedifferent ecological characteristics in terms of number of offspring andemergence pattern. [ABSTRACT FROM AUTHOR]

[Display omitted] • Bacillus velezensis MT9 and Pseudomonas choloraphis MT5 are two new strains. • These strains produce water-soluble antifungal and antibacterial compounds. • Pseudomonas choloraphis MT5 produces antifungal VOCs. • Both bacteria produce semiochemical VOCs active on the behavior of insects. • These strains are useful against citrus sooty mold caused by insect and fungal biofilm. Sooty mold is a plant disease caused by Aleurocanthus spiniferus , an alien insect spread widely in the South of Puglia region (Italy) that causes extensive damage to citrus crops. Sooty mold is a complex disease: the insect sucks the sap of the plant and expels a sugary liquid called honeydew which supports the growth of a black biofilm on the plant. This biofilm is made up of various types of fungi and, while not causing disease, it contributes to plant malaise by inhibiting photosynthesis. In this study, microbiological and chemical methods have been used to characterize two bacterial strains, Bacillus velezensis MT9 and Pseudomonas chlororaphis MT5, which were isolated from soil samples taken from vine-cultivated land and can be used as biocontrol agents (BCA). These bacteria were shown to produce antibacterial and antifungal activities in the form of water-soluble molecules and were effective in vitro in inhibiting the growth of two fungal strains, Penicillium sp. YM1 and YM2, isolated from citrus soot. In addition to water-soluble molecules, P. chlororaphis MT5 was shown to produce antifungal volatile organic compounds (VOCs). The VOCs produced by B. velezensis MT9 and P. chlororaphis MT5 were then identified by gas chromatography – mass spectrometry (GC–MS). Interestingly, some of the identified VOCs have previously been reported to have semiochemical activity in insects and, therefore, can interfere with chemical signaling in plant-insect-microbe interaction. Altogether these in vitro findings and pilot experiments with a limited set of plants indicate that Bacillus velezensis MT9 and Pseudomonas chlororaphis MT5 can effectively combat sooty mold possibly by acting on both the insects and the fungi that inhabit the black biofilm, paving the way for an innovative and sustainable tool to fight this disease. [ABSTRACT FROM AUTHOR]

We compared the efficiency of the reported primer pair and another version that we redesigned for discriminating tea spiny whitefly, Aleurocanthus camelliae Kanmiya and Kasai, an invasive tea pest in Japan, from another species, A. spiniferus(Quaintance), caught on yellow sticky traps in two tea fields in Kagoshima Prefecture, Japan. The reported primer pair enabled us to identify only 5.0-6.7% of individuals captured, whereas we were able to identify 73.3-75.0% of the captured individuals using the redesigned primer pair. These results suggest that the redesigned primer pair is more effective for monitoring the occurrence of A. camelliae in Japanese tea fields. [ABSTRACT FROM AUTHOR]

The invasive orange spiny whitefly (OSW) Aleurocanthus spiniferus has extended its distribution to non-native areas since the early 20th century. In a similar manner, the invasive tea spiny whitefly (TSW) A. camelliae has been expanding over East Asia in recent decades. In this study, the genetic diversity of OSW and TSW and of their important parasitoid wasp Encarsia smithi was investigated in China and Japan to enable more efficient biological control policies. We detected two phylogenetic groups (haplogroups A1 and A2) in OSW and three phylogenetic groups (haplotypes B1 and B2, and haplogroup B3) in TSW in China; however, only a single haplotype was detected in each whitefly species in Japan. Based on historical records and molecular data, OSW was considered to be native to China whereas TSW has probably expanded to China from a more southern location in the last 50 years; China appears to be the source region for OSW and TSW invading Japan. In E. smithi, two phylogenetic groups were detected in Japan: haplotype I, associated with OSW, and haplogroup II mostly associated with TSW, except in two locations. These data support the hypothesis that E. smithi parasitizing TSW in Japan did not originate from the existent population parasitizing OSW but was newly imported into Japan following the invasion of its host. [ABSTRACT FROM PUBLISHER]

Although Aleurocanthus spiniferus (Quaintance) (Hemiptera: Aleyrodidae) is a well known insect pest of tea plants, little information is available about its genetic structure and diversity. The present study used microsatellite markers to assess the genetic structure and diversity of this species on tea plants in China. For this purpose, 193 individuals from ten natural populations were analyzed using ten microsatellite markers. Our results indicated that the average number of alleles (A) across populations was 35.6, and all observed heterozygosities (H O ) were greater than 0.7, indicating an excess of heterozygosity and a relatively high level of genetic diversity among populations, and the number of private alleles per population ranged from 3 to 26. Pairwise F ST analysis suggested that the number of genetic differentiation events was moderate (0.05 < F ST < 0.15) between most of the populations. Mantel test indicated that genetic distance was not correlated to geographic distance. UPGMA dendrogram revealed that GX formed one cluster, separate from the other populations, and five clusters were generally formed according to STRUCTURE and GENELAND analyses. Molecular variance analysis revealed that more than 95% of variation was attributed to among samples within populations. High levels of migration rate were detected among five groups and migration rate was generally symmetrical in group pairs. Bottleneck test indicated that most populations had experienced a population bottleneck. [ABSTRACT FROM AUTHOR]

Introduction: Aleurocanthus spiniferus (Quaintance) is one further alien invasive pest that have been invading the south of Italy. From the EPPofirst report of the presence of A. spiniferus, in April 2008, Puglia was invaded northward by this polyphagous whitefly and new territories were infested more or less severely. Aims: This poster refers about recently occupied areas detailing local and urban outbreaks and population density per host plant species. Materials and Methods: We use direct observation on the field and digital camera-equipped stereoscope and Cryo-SEM on the laboratory for data confirmation and imaging. Results: We detail the invaded areas, confirming the spreading of this pest in almost all the Puglia region. Conclusions: The overall ecological preferences and behaviour of the pest are depicted in view of its control in urban areas. [ABSTRACT FROM AUTHOR]