Aphis Gossypii Glov Research Articles

Biochemical and insecticidal efficacy of clove and basil essential oils and two photosensitizers and their combinations on Aphis gossypii glover (Hemiptera: Aphididae)

The present study investigates the insecticidal and biochemical effects of two essential oils (EOs) and two photosensitizers against cotton aphids in a laboratory setting. The EOs evaluated were clove (Syzygium aromaticum L.) and basil (Ocimum basilicum), while the photosensitizers were rose bengal and rhodamine B. The individual median lethal concentrations (LC50) revealed that clove was ~4.44 times more potent than basil, and rhodamine B was ~1.34 times more potent than rose bengal. The mortality rates increased using higher concentrations of the photosensitizers and prolonging exposure time to sunlight. The most effective combination against adult aphids was found to be a mixture of sub-lethal concentrations of clove and rhodamine B, resulting in a mortality rate of 92.31%. Conversely, the combination of basil and rose bengal exhibited the lowest efficacy with a mortality rate of 33.33%. Biochemical analyses indicate that Rhodamine B, basil, and the basil-rhodamine B mixture (mixture C) significantly reduced trehalase activity. However, the protease activity significantly increased in aphids treated with rose bengal, clove, and the clove-rose bengal mixtures (mixtures A and B). The lipase activity is notably decreased upon treatment with rhodamine B and clove. Glutathione S-transferase (GST) activity decreased in aphids treated with rose bengal and the basil-rhodamine B mixtures (mixtures C and D), suggesting that GST did not play a role in detoxifying these compounds, thereby explaining the susceptibility of A. gossypii. Overall, the combination of essential oils and photosensitizers has demonstrated a synergistic effect in controlling Aphis gossypii, offering great potential as an effective strategy for aphid management.

Strain Streptomyces sp. P-56 Produces Nonactin and Possesses Insecticidal, Acaricidal, Antimicrobial and Plant Growth-Promoting Traits

Streptomycetes produce a huge variety of bioactive metabolites, including antibiotics, enzyme inhibitors, pesticides and herbicides, which offer promise for applications in agriculture as plant protection and plant growth-promoting products. The aim of this report was to characterize the biological activities of strain Streptomyces sp. P-56, previously isolated from soil as an insecticidal bacterium. The metabolic complex was obtained from liquid culture of Streptomyces sp. P-56 as dried ethanol extract (DEE) and possessed insecticidal activity against vetch aphid (Medoura viciae Buckt.), cotton aphid (Aphis gossypii Glov.), green peach aphid (Myzus persicae Sulz.), pea aphid (Acyrthosiphon pisum Harr.) and crescent-marked lily aphid (Neomyzus circumflexus Buckt.), as well as two-spotted spider mite (Tetranychus urticae). Insecticidal activity was associated with production of nonactin, which was purified and identified using HPLC-MS and crystallographic techniques. Strain Streptomyces sp. P-56 also showed antibacterial and antifungal activity against various phytopathogenic bacteria and fungi (mostly for Clavibacfer michiganense, Alternaria solani and Sclerotinia libertiana), and possessed a set of plant growth-promoting traits, such as auxin production, ACC deaminase and phosphate solubilization. The possibilities for using this strain as a biopesticide producer and/or biocontrol and a plant growth-promoting microorganism are discussed.

Effects of transgenic cotton lines expressing dsAgCYP6CY3-P1 on the growth and detoxification ability of Aphis gossypii glover.

The pest Aphis gossypii Glover globally causes considerable economic losses on various crops by its feeding damage and disease transmission. Transgenic plants that produce double-stranded RNA (dsRNA) targeted to insect genes are being developed as a pest control strategy. In this study, we evaluated the effects of transgenic cotton-mediated RNA interference (RNAi) on the growth and detoxification ability of A. gossypii after the transgenic cotton lines expressing dsAgCYP6CY3-P1 (the TG cotton lines) were obtained on the basis of exploring the functions of CYP6CY3 in our previous research. The developmental time of third- and fourth-instar nymphs which fed on the TG cotton lines were significantly prolonged. Life table parameters showed that the fitness of cotton aphids from the TG cotton lines decreased. Additionally, the relative expression level of CYP6CY3 in cotton aphids which fed on the TG cotton lines was significantly reduced by 47.3 % at 48 h compared with that from the nontransgenic cotton (the NT cotton). Bioassay showed that silencing of CYP6CY3 increased mortality of the nymphs to imidacloprid by 28.49 % (at 24 h) and to acetamiprid by 73.77 % (at 48 h), respectively. These results indicated that the TG cotton lines delayed the growth and development of A. gossypii, but also decreased population density and increased its sensitivity to imidacloprid and acetamiprid, respectively. The results provide further support for the development and application of plant-mediated RNAi. © 2022 Society of Chemical Industry.

Efficacy of Certain Insecticides and Mineral Oil in Controlling Aphid, Aphis gossypii Glov. and Papaya Ringspot Virus in Squash at Kafr El-Sheikh Governorate

Efficacy of Certain Insecticides and Mineral Oil in Controlling Aphid, Aphis gossypii Glov. and Papaya Ringspot Virus in Squash at Kafr El-Sheikh Governorate

Functional analysis of cyantraniliprole tolerance ability mediated by ATP-binding cassette transporters in Aphis gossypii glover

Cyantraniliprole, a second-generation anthranilic diamide insecticide, is widely used to control chewing and sucking pests. ATP-binding cassette transporters (ABCs) are a ubiquitous family of membrane proteins that play important roles in insect detoxification mechanisms. However, the potential effects of ABCs on cyantraniliprole-resistance remain unclear. In the present study, synergism bioassays revealed that verapamil, an ABC inhibitor, increased the toxicity of cyantraniliprole by 2.00- and 12.25-fold in the susceptible and cyantraniliprole-resistant strains of Aphis gossypii. Based on transcriptome data, the expression levels of ABCB4, ABCB5, ABCD1, ABCG4, ABCG7, ABCG13, ABCG16, ABCG17, ABCG26 and MRP12 were upregulated 1.56-, 1.32-, 1.51-, 2.03-, 1.65-, 1.50-, 4.18-, 6.07-, 4.68- and 4.69-fold, respectively, in the cyantraniliprole-resistant strain (CyR) compared to the susceptible strain (SS), as determined using RT-qPCR. Drosophila melanogaster ectopically overexpressing ABCB5, ABCG4, ABCG7, ABCG16, ABCG17, ABCG26 and MRP12 exhibited significantly increased tolerance to cyantraniliprole by 11.71-, 2.39-, 4.85-, 2.06-, 3.75-, 4.20- and 3.50-fold, respectively, with ABCB5 and ABCG family members being the most effective. Furthermore, the suppression of ABCB5, ABCG4, ABCG7, ABCG16, ABCG17, ABCG26 and MRP12 significantly increased the sensitivity of the CyR strain to cyantraniliprole. These results indicate that ABCs may play crucial roles in cyantraniliprole resistance and may provide information for shaping resistance management strategies.

Chemosensory proteins confer adaptation to the ryanoid anthranilic diamide insecticide cyantraniliprole in Aphis gossypii glover

Chemosensory proteins (CSPs) are a class of small transporter proteins expressed only in arthropods with various functions beyond chemoreception. Previous studies have been reported that CSPs are involved in the insecticide resistance. In this study, we found that AgoCSP1, AgoCSP4, and AgoCSP5 were constitutively overexpressed in an insecticide-resistant strain of Aphis gossypii and showed higher expression in broad body tissue (including fat bodies) than in the midgut but without tissue specificity. However, the function of these three upregulated AgoCSPs remains unknown. Here, we investigated the function of AgoCSPs in resistance to the diamide insecticide cyantraniliprole. Suppression of AgoCSP1, AgoCSP4 and AgoCSP5 transcription by RNAi significantly increased the sensitivity of resistant aphids to cyantraniliprole. Molecular docking and competitive binding assays indicated that these AgoCSPs bind moderate with cyantraniliprole. Transgenic Drosophila melanogaster expressing these AgoCSPs in the broad body or midgut showed higher tolerance to cyantraniliprole than control flies with the same genetic background; AgoCSP4 was more effective in broad body tissue, and AgoCSP1 and AgoCSP5 were more effective in the midgut, indicating that broad body and midgut tissues may be involved in the insecticide resistance mediated by the AgoCSPs examined. The present results strongly indicate that AgoCSPs participate in xenobiotic detoxification by sequestering and masking toxic insecticide molecules, providing insights into new factors involved in resistance development in A. gossypii.

Establish real-time monitoring models of cotton aphid quantity based on different leaf positions in cotton seedlings

Cotton aphids, Aphis gossypii glover, are major pest threats to cotton plants, leading to quality and yield loss of cotton. Rapid and accurate evaluation on the occurrence and quantity of cotton aphids can help precision management and treatment of cotton aphids. The occurrence rules of cotton aphids on different leaf positions in cotton seedling stage for two cultivars of cotton were studied. The quantity of cotton aphids in the whole cotton seedlings were predicted based on the single leaf cotton aphid quantity. The correlation analysis results showed that cotton aphids of single leaf were significantly and positively correlated with the infected time, the all leaves of the whole plant, the whole plant contained all leaves and branches. The variance analysis results showed that cotton aphids of single leaf were significant difference with the extension of infected time. Based on different leaf positions, monitoring models were constructed respectively. The modelling set’s determination coefficient of ‘Xinluzao-45’ was greater than 0.8, while ‘Lumainyan-24’ was greater than 0.6. The best monitoring leaf position was the third for ‘Xinluzao-45’, the sixth for ‘Lumianyan-24’. From the data analysis, we can realize that it is feasible to construct a monitoring model based on the occurrence of cotton aphid in one leaf in cotton seedling, and different cotton varieties have different leaf positions. This will greatly reduce the investment of manpower and time.

Suitability of five plant species extracts for their compatibility with indigenous Beauveria bassiana against Aphis gossypii Glov. (Hemiptera: Aphididae)

BackgroundThe cotton aphid, Aphis gossypii Glov. (Hemiptera: Aphididae), is a major insect pest on a wide range of plants that causes high damage and transmits plant viruses. This study was carried out to evaluate an indigenous isolate, Beauveria bassiana (Bb), and extracts of 5 plant species: Psiadia penninervia, Pulicaria crispa, Euryops arabicus, Salvia officinalis, and Ochradenus baccatus against A. gossypii, as individual and combined treatments to estimate their compatibility under laboratory conditions. Also, the antifungal activity of these plant extracts against B. bassiana was evaluated.ResultsLC50 value was 8.64 × 104 spores/ml of Bb against A. gossypii, while LC50 values of the tested 5 plant extracts on A. gossypii were 103.64, 879.92, 747.90, 783.28, and 262.42 μg/ml for P. penninervia, P. crispa, E. arabicus, S. officinalis, and O. baccatus, respectively. Both P. penninervia and O. baccatus extracts had the highest antifungal activities against Bb and were significantly different from the other 3 plant extracts. After 24 h of treatment with the combination of Bb and each extract, no effect for these combinations on A. gossypii mortality was recorded. Meanwhile, 5 days after treatment, the combined treatments between Bb and each plant extract achieved a significant increase in mortality than that of the single treatment with Bb or plant extract, except for P. penninervia extract, which did not achieve a significant mortality increase when combined with B. bassiana than that of its single treatment.ConclusionP. penninervia extract was not compatible with B. bassiana, but the other tested 4 plant extracts were compatible with B. bassiana. These 4 plant extracts could be used to control aphids in combinations with B. bassiana. Further laboratory and field investigations are needed to examine the effects of these plant extracts on other insect pests or associated beneficial insects.

Evaluation of some leaf and seed extracts for their insecticidal properties against Aphis gossypii glover (hemiptera: aphididae)

The insecticidal properties of leaf extracts of Carica papaya, Leucas aspera and seed extracts of Daturastramonium and Mucuna pruriens were evaluated against Aphis gossypii Glover (Hemiptera: Aphididae) under laboratory conditions. The mortality of aphids (80.0%) was more from D. stramonium seed extract (10ml/l) with LD50 of 0.39% followed by C. papaya leaf extract which caused mortality of 72.5% (10ml/l) with LD50 0.96%. The mortality of A. gossypii in M. pruriens seed extract was 70.0% with LD50 0.65% however the mortality was found to be non significant in L. aspera extract.

Multiple ATP-binding cassette transporters genes are involved in thiamethoxam resistance in Aphis gossypii glover

ATP-binding cassette (ABC) transporters represent the largest known group of efflux pumps, utilizing ATP to translocate a broad spectrum of substrates across lipid membranes, which play an important role in phase III of the detoxification process. The presence of ABC transporters and their potential association with insecticide resistance have not been investigated in Aphis gossypii, one of the most economically important agricultural pests worldwide. In this study, the ABC transporter inhibitor-verapamil significantly increased thiamethoxam toxicity against resistant cotton aphids, suggesting that ABCs are involved in thiamethoxam resistance. ABC transporter genes were identified using the A. gossypii genome database and transcriptome data. A total of 69 ABC transporters were identified and grouped into seven subfamilies (A-G), including 4 ABCAs, 5 ABCBs, 25 ABCCs, 2 ABCDs, 1 ABCE, 4 ABCFs and 30 ABCGs. Of these ABC transporters, 53 were predicted to be functional, 19 were full transporters, 30 were half-transporters and 4 had two NBDs. Subfamilies C and G accounted for 77% (32 and 45%, respectively) of the genes. The transcripts of 20 of 26 ABCs based on the transcriptome were upregulated, and ABCA1, ABCA2, ABCB1, ABCB4, ABCB8, ABCD1, ABCD2, ABCE1, ABCF1, ABCF3, ABCG7, ABCG15, ABCG17, ABCG24, ABCG27, ABCG30, MRP1, MRP7, MRP14 and MRP21 transcripts were significantly increased in the thiamethoxan resistant strain compared to the susceptible strain with qRT-PCR. The suppression of overexpressed ABCs (ABCA2, ABCD1, ABCD2, ABCE1 and ABCG15) significantly increased the thiamethoxam sensitivity of resistant aphids. These results suggest that ABC transporters might be involved in thiamethoxam resistance in A. gossypii and will facilitate further work to validate the functional roles of these ABCs in thiamethoxam resistance. These results are useful for understanding the multiple resistance mechanisms of thiamethoxam and the management of insecticide-resistant cotton aphids.

UDP-glucosyltransferases potentially contribute to imidacloprid resistance in Aphis gossypii glover based on transcriptomic and proteomic analyses

The cotton aphid, Aphis gossypii Glover, is a destructive global crop pest. Control of A. gossypii has relied heavily on the application of chemical insecticides. The cotton aphid has developed resistance to numerous insecticides, including imidacloprid, which has been widely used to control cotton pests in China since the 1990s. Our objective was to investigate the potential role of UDP-glycosyltransferases (UGTs) in imidacloprid resistance based on transcriptomic and proteomic analyses of field-originated imidacloprid-resistant (IMI_R) and -susceptible (IMI_S) A. gossypii clones. The transcriptomic and proteomic analyses revealed that 12 out of 512 differentially expressed genes and three out of 510 differentially expressed proteins were predicted as UDP-glycosyltransferase (UGT). Based on quantitative real-time PCR analysis, nine UGT genes, UGT343A4, UGT344A15, UGT344A16, UGT344B4, UGT344C7, UGT344C9, UGT344N4, UGT 24541, and UGT7630, were up-regulated in the IMI_R clone compared to the IMI_S clone. Meanwhile, UGT344A16, UGT344B4, UGT344C7, and UGT344N4 were overexpressed at the protein level based on western blot analysis. Furthermore, knockdown of UGT344B4 or UGT344C7 using RNA interference (RNAi) significantly increased sensitivity to imidacloprid in the IMI_R clone. In conclusion, UGTs potentially contributed to imidacloprid resistance in A. gossypii originating from cotton-growing regions of China. These results provide insights into the way we study insecticide resistance in cotton aphids.

Efficiency of botanical pesticides against some pests infesting hydroponic cucumber, cultivated under greenhouse conditions

Greenhouse cultivation of vegetables, especially cucumber in hydroponic/soilless culture, has been developed in different parts of the world. There is an expanding interest in hydroponics because they can produce fresh food closer to urban areas. The objective of this study was to evaluate the efficiency of the biopesticides: matrine (extract from Sophora flavescens), spintoram (derived from soil bacterium Saccharopolyspora spinosa), azadirachtin (neem extract), and Annona squamosa (custard apple extract) against the cotton aphid (Aphis gossypii Glov.) and the two-spotted spider mite, (Tetranychus urticae Koch.). A drip-irrigation hydroponics system (DIHS) was designed and used for this study. Fourteen-day-old seedlings of cucumber plants were shifted in DIHS, and nutrient requirements were maintained during the period of experiment. Randomized complete block design (RCBD) was used for this experiment with 3 replicates and with 5 treatments. Data were collected 24 h pre-treatment and 1, 3, 7, and 14 days post-treatment. Results revealed that the custard apple extract showed the highest efficiency (80 and 76%) reduction against the aphid and the mite, respectively, followed by matrine (legend) and neem extract (73%), and spintoram (radiant) (69%) in case of the aphid, while it was followed by matrine (legend) (75%), spintoram (radiant), (66%), and neem extract (56%) in the case of the mite.

Insecticidal effect of juglone and its disturbance analysis in metabolic profiles of Aphis gossypii glover using 1H NMR-based metabonomics approach

Juglone shows a wide range of biological activities but its insecticidal effect and mechanism on Aphis gossypii has not been reported up to now. In this study, on the basis of insecticidal effect research, a 1H NMR-based hemolymph metabonomics analysis approach was applied to comprehensively and holistically investigate the toxic mechanism of juglone on A. gossypii. The sublethal effect of juglone was administered to A. gossypii Glover up to 12 h post treatment with the healthy insects as controls. By means of pattern recognition analysis, the metabolic profile of juglone treatment group was clearly distinct from that of control group. On the basis of biochemical traits measurement of A. gossypii hemolymph, the variations of a number of metabolites such as glucose, trehalose, betaine, valine, alanine, lactate, taurine, dimethylamine, and putrescine were determined and discussed. These results revealed that the juglone caused a disturbance of A. gossypii physiology by affecting its metabolomics profile of hemolymph. The current work may provide valuable clues for understanding the insecticidal mechanisms of juglone, as well as show the potential power of the combination of the NMR technique and the pattern recognition method for pesticide biochemistry research.

English

Yellow pepper (Capsicum annuum L.) is the second market gardening crop after tomato, and subsequently, a major source of income to farmers in Nigeria. Pests and diseases reduce yields and quality of marketable fruits. A study was conducted in Ibagwa-Agu, Lejja, Edem, Alor-Uno and Eha-Alumona agro-based communities of Nsukka Local Government Area to assess the economic implications of insect infestation and control strategies on yellow pepper yield. Data on insect pests was collected using the modified Whittaker sampling techniques from July to September 2015, while farming practices and economic consequences of pest infestation were monitored using questionnaires in December 2015. A total of 2,279 insects comprising 10 pests and 2 predators were collected. Myzus persicae Sulzer (27.6% of total collections), Bemisia tabaci Genn. (21.1%), Aphis gossypii Glov. (14.1%) and Zonocerus variegatus Gestro(7.99%) were the four prominent insect pests, while Ladybird beetle larva of Harmoni axyridis (2.3%) and praying mantis Stagmonantis crolina (1.4) were the main predators encountered. Mean percentage of plants attacked and yield losses were significantly (P <0.05) lower in communities with a high percentage of farmers utilizing cultural control methods. A higher percentage of the farmers were females. Farmers in Edem, Eha-Alumona, Lejja, Alor-Uno and Ibagwa-Agu in Nsukka Local Government Area of Enugu State therefore experience enormous economic loss in yellow pepper cultivation from the infestation of insect pests. Communities with a high percentage of farmers practicing cultural control methods had fewer plants attacked, while the predators were also more abundant. Further research is needed to ascertain the efficacy of these cultural methods. Key words: Yellow pepper, Insect pests, Yield reduction, Farmers’ cropping practices, Control measures, Gender perception.

Influence of The Different Onion Varieties on the Population Density of the Main Insect Pests Infesting Onion Crop in Kafr El-Shekh Region.

The current experiments were carried out in the Research Farm of the Agricultural Research Station in Sakha, Kafr El Sheikh Governorate, where three main onion varieties (Giza 6, Giza 20 and Giza Red) were cultivated, during 2013/14 and 2014/15 seasons, to study the influence of different onion varieties on the population density of the most important insect pests. The highest populations of all investigated insects were recorded on variety Giza 6 followed by Giza 20 and Giza Red during the two-successive season. This study showed that the highest average numbers of the onion thrips Thrips tabaci Lind. on Giza 6 were 316.6 ± 36.6 and 286.4± 34.1 nymphs during the first and second season, respectively. The highest average number of the onion aphid Aphis gossypii Glov was also recorded on Giza 6 and represented by 1124 ± 22.4 and 1061± 18.7 individuals, during the first and second season, respectively. The highest average numbers of the Onion maggot Dalia allairia Fonseca was also recorded on Giza 6 and represented by 37.7 ±7.6 and 41.3 ±8.5 during the first and secon season, respectively. The onion varieties showed significant differences in their attraction to T. tabaci and A. gossypii, but not for D.allairia. For the Integrated Pest Management strategy for onion crop, Giza 6 has to be excluded from the approach of crop breeders and farmers due to its higher susceptibility for infestation.

Insecticides on the basis of analogs of insect juvenile hormones

Analogs of juvenile hormones (JHAs)—azadirachtin (NeemAzal, EC (10 g/L), fenoxycarb (Phasis, WP (250 g/kg), and pyriproxyfen (Admiral, EC (100 g/L) and Inoxyfen, EC (100 g/L)—have been tested. The effectiveness of insectoacaricide NeemAzal in regulating the population numbers of sucking insects was assessed using glasshouse cucumber in Leningrad oblast. Three applications of this product in 0.5% concentration effectively protected this culture against red spider mite (Tetranychus urticae Koch.) and onion thrips (Thrips tabaci Lind) and, less significantly, against melon aphid (Aphis gossypii Glov). Insecticide Phasis protected vineyards against European vine moth (Lobesia botrana Den&Schiff). Juvenoid Admiral effectively decreased the number of imagoes and larvae of greenhouse whitefly (Trialeurodes vaporariorum Wsfw.) in glasshouse cucumber and tomato in different regions of Russia, while Inoxyfen protected apples against codling moth (Cydia pomonella). The tested products belong to the group of biorational pesticides that can be used in ecologically sound systems of plant protection.

EFFECT of SEAWEEDS and ORGANIC FOLIAR FERTILIZERS on the COTTON PESTS, PREDATORS, YIELD and FIBER QUALITY in COTTON

A field experiment was carried out in Aydin region, Turkey during the two successive cotton growing seasons 2010 and 2011. The compounds have did not affect the population amount of Empoasca spp., Bemisia tabaci Genn., Frankliniella spp., whereas they affected Aphis gossypii Glov. and Liriomyza trifolii Burgess infestation. The highest population of Aphis gossypii was observed in Active Black Up treatment. On the other hand, the highest damage caused by L. trifolii was in Promina treatment. Among the predators, population in Thysanoptera order was significantly different in the treatments. More thrips populations were observed in Promina. The application of compounds significantly affected on the yield. The highest yield was obtained from Aminoquick treatmetn that has 95% organic matter and produced 28% more yield compared to the control. Treatments had no significant effects on plant height, lint percentage, boll weight, fiber properties, except for number of boll per plant and micronaire. The results showed that these compounds increased the yield, did not enhance the pests' population and not harmful to predators except for Thysanoptera. Thus, containing seaweeds and more organic foliar fertilizer compounds should be considered in integrated management of organic or conservative cotton fields.

Rapid evolution of symbiotic bacteria populations in spirotetramat-resistant Aphis gossypii glover revealed by pyrosequencing

Aphis gossypii is one of the most economically important insect pests for agriculture worldwide. Aphids have developed symbiotic associations with bacterial species, which has led to morphological and molecular differences, such as body color and insecticide resistance. Adults and 3rd instar nymphs of a laboratory-selected spirotetramat-resistant strain of cotton aphid presented 579-fold and 15-fold higher resistance to spirotetramat, respectively, than a susceptible strain (Pan et al., 2015; Peng et al., 2016). In this study, we found that antibiotics, especially ampicillin and tetracycline, increased spirotetramat toxicity in resistant aphids. We also characterized all of the bacterial endosymbionts in these two clones by sequencing the 16S rRNA genes of the endosymbiont. The total reads could be clustered into 3534 operational taxonomic units (OTUs) that showed 97% similarity and belonged to six abundant phyla. Proteobacteria and Firmicutes dominated in the two strains, and the most abundant families were Enterobacteriaceae, Lactobacillaceae and Rhodobiaceae. The genera Arsenophonus, Anderseniella, Buchnera and Lactobacillus were most abundant in the susceptible strain, whereas a significant decrease in abundance of Anderseniella and a great increase in abundance of Arsenophonus and Lactobacillus were observed in the resistant strain. Certain identified species had low sequence similarity to the reported species, which indicates the possibility of novel taxa. The type and abundance of different bacterial groups varied significantly between the two strains. The insecticide selection pressure could be the reason for the observed shift in the bacteria groups. These results increase our understanding of the symbiotic relationships between bacteria and their hosts under insecticide stress and provide clues for the development of potential control techniques against this cotton aphid.

Potato virus Y in the Russian Far East (epidemiology, strains, and damage)

Biological, physical, chemical, and antigenic characteristics of a potato virus Y are investigated. Significant strain diversity of this pathogen is found in the Far East of Russia. There are ten strains affecting potato and weeds. It is shown that PVYntm strain has a remote immunochemical affinity with common PVY strain. In the Far East of Russia, the most widespread aphid vectors of this virus are Myzus percicae Sulz., Aulacorthum solani Kalt., and Aphis gossypii Glov.

전남지역 시설재배 수국에 발생히는 주요해충의 발생소장과 방제약제 선발

This study has been made for the seasonal occurrence of major insect pests which occurred in greenhouse-grown hydrangea and the selection of pesticide from March 2013 to December 2014. Major insect pests included Tea red spider mite (Tetranychus kanzawai Kishida), Garden thrips (Frankliniella intonsa), and Melon aphid (Aphis gossypii glover). And among them, insect pests requiring being controlled were T. kanzawai, and F. intonsa. With regard to seasonal occurrence, T. kanzawai occurred in mid-March, and showed the peak period of occurrence in early June, and then showed that it tended to rapidly decrease. F. intonsa started to occur from early April, and its peak period of occurrence was late-June. With regard to the selection of pesticide, in case of T. kanzawai, 4 types such as abamectin emulsifiable concentrate showed a high control value of 93% or above, and in case of F. intonsa, 2 types such as acetamiprid wettable powder too. No pesticides with which hydrangea was treated had phytotoxicity. On the other hand, with regard to the sticky trap