Acta Entomologica Sinica

Differential expression of multicopper oxidase 4 gene and biological effects after RNAi and feeding on different rice varieties in Sogatella furcifera (Hemiptera: Delphacidae)

JIA Hao-Kang, LIU Yu-Di, HOU Mao-Lin

2019, 62(12): 1351-1358. doi:10.16380/j.kcxb.2019.12.001

Abstract ( 77 )

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【Aim】 The study aims to analyze the expression difference of multicopper oxidase 4 gene and the biological effects after RNAi and feeding on different rice varieties in Sogatella furcifera, so as to provide a theoretical basis for fundamental function research of this gene. 【Methods】 The nucleotide and amino acid sequences of MCO4 gene were analyzed by bioinformatic methods. The MCO4 gene in the 3rd instar nymphs of S. furcifera was silenced by RNAi, the silencing efficiencies of microinjection method and feeding method were compared, and the effect of RNAi of MCO4 gene on the survival rate of the 3rd instar nymphs was studied. After feeding on rice varieties with different insect resistance for 24 h, the changes in the expression level of MCO4 in S. furcifera adults were detected by RT-qPCR, and their body weight was detected. 【Results】 The full-length cDNA of MCO4 gene is 2 166 bp, encoding 721 amino acids. RNAi by microinjection method successfully silenced the MCO4 gene of S. furcifera, with much higher silencing efficiency than that by feeding method. The survival rate of the 3rd instar nymphs with silenced MCO4 was significantly lower than that of the normal nymphs. Compared with the adults fed on the susceptible cultivar TN1, the adults fed on the resistant variety IR26 had significantly higher expression level of MCO4 and significantly reduced body weight. 【Conclusion】 Microinjection method can more efficiently silence the MCO4 gene of S. furcifera. Silence of MCO4 gene has significant effects on the survival rate of S. furcifera, and we speculate that MCO4 plays an important role in feeding of S. furcifera on rice.

Role of DaFOXO1 in the regulation of superoxide dismutase gene expression and developmental duration of summer diapause pupae of Delia antiqua(Diptera: Anthomyiidae)(In English)

PENG Zhu-Qing, HAO You-Jin

2019, 62(12): 1359-1368. doi:10.16380/j.kcxb.2019.12.002

Abstract ( 34 )

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【Aim】 The aim of this study is to investigate the role of DaFOXO1 in the regulation of superoxide dismutase (SOD) gene expression and the developmental duration of summer diapause pupae of the onion fly, Delia antiqua. 【Methods】 Genes encoding copper-zinc superoxide dismutase (DaCu/Zn SOD) and manganese superoxide dismutase (DaMn SOD), downstream genes of DaFOXO1, were identified from the transcriptome data of D. antiqua. The features of amino acid sequences, subcellular localization and phylogeny of DaCu/Zn SOD and DaMn SOD of D. antiqua were analyzed by using bioinformatic tools. The expression patterns of DaFOXO1, DaCu/Zn SOD, and DaMn SOD at different developmental stages of summer diapause pupae of D. antiqua were determined by qRT-PCR. The effect of knocking down DaFOXO1 by RNAi on the expressions of DaCu/Zn SOD and DaMn SOD, the activity variations of DaCu/Zn SOD and DaMn SOD and the developmental duration of summer diapause pupae of D. antiqua were further analyzed. 【Results】 The open reading frame (ORF) of DaCu/Zn SOD (GenBank accession no. KR072551) of D. antiqua is 459 bp in length and encodes 153 amino acids with a predicted molecular weight (MW) of 22.4 kD and an ioselectric point (pI) of 6.44, which belongs to a cytoplasmic Cu/Zn SOD. The ORF of DaMn SOD (GenBank accession no. KR072549) is 648 bp in length and encodes 216 amino acids with a predicted MW of 24.4 kD and a pI of 8.85, which belongs to mitochondrial Mn SOD. Amino acid sequence alignment revealed that DaCu/Zn SOD and DaMn SOD share 75%-94% identity with their homologues from other 10 species of Diptera, and contain typical SOD family domains. Phylogenetic analysis showed that they formed a robust phylogenetic branch with their homologues in Lucilia cuprina. qRT-PCR analysis revealed that the expression levels of DaFOXO1 were higher at the pre-diapause and post-diapause stages, but lower at the diapause stage. Higher expression of DaCu/Zn occurred at the diapause stage and post-diapause stage. However, the highest expression level of DaMn SOD was detected at the prediapause stage and diapause stage, and followed by at post-diapause stage. Knockdown of DaFOXO1 by RNAi significantly decreased the expression levels of DaCu/Zn SOD and DaMn SOD, and the activities of their corresponding enzymes, leading to a significantly extended duration of summer diapause pupae. 【Conclusion】 The results suggest that DaCu/Zn SOD and DaMn SOD are important members of FOXO1 signaling network, and DaFOXO1 plays an important role in the regulation of the duration of summer diapause pupae of D. antiqua.

Expression and ligand binding characteristics of chemosensory protein AipsCSP8 of Agrotis ipsilon (Lepidoptera: Noctuidae)

SU Xu, ZHANG Yong-Jun, GENG Ting, LI Jing, GU Shao-Hua

2019, 62(12): 1369-1378. doi:10.16380/j.kcxb.2019.12.003

Abstract ( 57 )

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【Aim】 The aim of this study is to explore the gene expression profiles and ligand binding characteristics of the chemosensory protein AipsCSP8 of Agrotis ipsilon. 【Methods】 The expression levels of AipsCSP8 in the head, thorax, abdomen, leg, wing, pheromone gland (accessory gland), antenna, proboscis and labial palp of adults of A. ipsilon and the antennae of adults before and after emergence were determined by qRT-PCR. The recombinant protein AipsCSP8 was harvested by in vitro prokaryotic expression system, and its binding characteristics to 24 sex pheromones, 22 plant volatiles and 10 chemical pesticides were determined by fluorescence binding assay. 【Results】 The qRT-PCR results indicated that the expression level of AipsCSP8 was the highest in the leg and labial palp of male adults, followed by in the accessory gland and the antenna of male adults. While in female adults, the expression level of AipsCSP8 was the highest in the antenna, followed by in the leg, pheromone gland and labial palp. In addition, the expression levels of AipsCSP8 in the antennae of males and females reached the peak on the 1st day before emergence and on the day of emergence, respectively. The results of fluorescence competitive binding assay showed that AipsCSP8 had strong binding capabilities with dibutyl phthalate, phenylacetaldehyde and avermectin, with the dissociation constant Ki values of 14.6, 17.2 and 12.9 μmol/L, respectively. 【Conclusion】 AipsCSP8 may be involved in the olfactory behavior and taste recognition of A. ipsilon and play a role in the perception of chemical pesticides.

Screening of reference genes for quantitative real-time PCR in Lygus pratensis (Hemiptera: Miridae)

JIA Bing, MA Yi, PANG Bao-Ping, SHAN Yan-Min, BAO Qing-Long, HAN Hai-Bin, TAN Yao

2019, 62(12): 1379-1391. doi:10.16380/j.kcxb.2019.12.004

Abstract ( 53 )

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【Aim】 To screen out the most stably expressed reference genes in Lygus pratensis under specific conditions. 【Methods】 qRT-PCR was adopted to determine expression levels of 10 candidate reference genes including alpha-tubulin, beta-tubulin, actin, elongation factor, succinate dehydrogenase, ubiquitin, transcription initiation factor TFIID subunit, glutathione S-transferase, ribosomal protein L32, and TATA-box binding protein genes in six categories of samples of L. pratensis including different sex adults, different adult tissues, different developmental stages, adults with different lambdacyhalothrin resistance, and adults respectively exposed to different temperatures and different insecticides. BestKeeper, geNorm, NormFinder and RefFinder were adopted to analyze the mRNA expression stability of the candidate reference genes. 【Results】 According to the results of different analysis methods based on the effective qRT-PCR data, it was concluded that the most stably expressed reference gene was RPL32 for different adult tissues and adults of L. pratensis with different lambda-cyhalothrin resistance. The most stably expressed reference genes for the groups of adults exposed to different temperatures, different sex adults, adults exposed to different insecticides and different developmental stages were UBQ, SDHA, β-tubulin and TAF, respectively. Based on the comprehensive analysis from geNorm and RefFinder calculation, the best combinations of stably expressed reference genes for the groups of different adult tissues, different sex adults, different developmental stages, adults with different lambda-cyhalothrin resistance, and adults exposed to different temperatures and different insecticides were RPL32+TAF, SDHA+GST, TAF+GST+UBQ, RPL32+GST, UBQ+ACT+β-tubulin and β-tubulin+TAF+RPL32, respectively. 【Conclusions】 All the most stably expressed reference genes and their best combinations obtained from this study could be acceptable as reference genes for gene expression analysis in L. pratensis for future studies.

Changes in the activities of antioxidant enzymes and detoxification enzymes in vector aphid Sitobion avenae (Homoptera: Aphididae) and non-vector aphid Rhopalosiphum padi (Homoptera: Aphididae) feeding on wheat plants infected with Barley yellow dwarf virus

TONG Ze-Qian, MENG Lin-Qin, SU Dan, ZHANG Chi, HU Zu-Qing

2019, 62(12): 1392-1399. doi:10.16380/j.kcxb.2019.12.005

Abstract ( 32 )

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【Aim】 Yellow dwarf disease caused by barley yellow dwarf virus (BYDV) is one of the most important plant diseases that affects the production of wheat in China. GAV is the major strain of BYDV in China. Based on field investigation, BYDV-GAV, vector Sitobion avenae and non-vector Rhopalosiphum padi often occur together, which may cause serious losses to wheat yield. This study aims to investigate the activities of antioxidant enzymes and detoxification enzymes in both vector and non-vector aphids exposed to BYDV, so as to provide a reference for revealing the physiological and biochemical mechanisms of virus-aphid interaction. 【Methods】 The activities of antioxidant enzymes including peroxidase (POD), superoxide dismutase (SOD) and catalase (CAT), and detoxification enzymes including acyl carrier protein (ACP), alkaline phosphatase (AKP) and acetyl cholinesterase (AchE), in S. avenae and R. padi adults fed on healthy wheat plants (the blank control group), wheat plants harmed by the 3rd instar nymphs of avirulent Schizaphis graminum for 72 h (the conditional control group) and wheat plants infected with BYDV-GAV (transmitted by the 3rd instar nymphs of S. graminum infected with BYDV-GAV for 72 h) (the treatment group) for 7 d were measured by biochemical method. 【Results】 The activities of POD, SOD and AKP in S. avenae adults fed on wheat plants infected with BYDV-GAV for 7 d were significantly increased as compared with those in the blank control group, but showed no significant difference from those in the conditional control group. And the activities of the above enzymes in S. avenae adults in the conditional control group were significantly higher than those in the blank control group. The activities of SOD, AKP and AchE in R. padi adults fed on wheat plants infected with BYDV-GAV for 7 d were significantly decreased, while the ACP activity was significantly increased as compared with those in the blank control group. And only the ACP activity in the treatment group was significantly increased as compared with that in the conditional control group. The activities of AKP and AchE in R. padi adults in the conditional control group were significantly lower than those in the blank control group, while the ACP activity in the conditional control group was significantly higher than that in the blank control group. 【Conclusion】 After feeding on wheat plants infected with BYDV-GAV, the increase of the activities of POD, SOD and AKP in vector aphid S. avenae adults is caused by previous aphid infestation, and has no relationship with BYDV-GAV. After feeding on wheat plants infected with BYDV-GAV, the decrease of the AKP and AchE activities in non-vector aphid R. padi adults is caused by previous aphid infestation, and the decrease of SOD activity is caused by the comprehensive effect of previous aphid infestation and BYDV-GAV, while BYDV-GAV and previous aphid infestation can increase the ACP activity.

Effects of the metabolites of Lactobacillus brevis on the oviposition selection of Drosophila melanogaster

YAN Qin, WANG Ming-Liang, HUA Lei, WANG Jie, ZHANG Hong-Yu, LIU Yu-Hong, BAI Peng, FU Hui, ZHANG Jun-Jie, LIU Wei

2019, 62(12): 1400-1408. doi:10.16380/j.kcxb.2019.12.006

Abstract ( 32 )

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【Aim】 This study aims to investigate the oviposition selection of Drosophila melanogaster to aerobic and anaerobic metabolites of Lactobacillus brevis, and to elucidate the underlying mechanism and biological significance of their effects on Drosophila oviposition behavior. 【Methods】 The oviposition preference of female adults of D. melanogaster was assayed by using the two-choice apparatus. The sensory modality that mediates this behavior was studied by using dark conditions, olfactory mutants and flies with forelegs surgically removed. The developmental duration and survival rate of offspring were determined to evaluate the biological significance of the oviposition avoidance to lactic acid. The intestinal epithelial cell proliferation was observed by immunofluorescence. 【Results】 The female adults of D. melanogaster avoided laying eggs on food covered with metabolites of L. brevis by anaerobic fermentation, with the oviposition index of -0.47. The concentration of the metabolite lactic acid was 0.4 mmol/L under the aerobic condition, while it was 126.8 mmol/L under the anaerobic condition. Female adults of D. melanogaster avoided laying eggs on the food with lactic acid, and the oviposition index decreased with lactic acid in a dosage dependent manner. D. melanogaster had obvious oviposition avoidance to lactic acid. The oviposition avoidance response was impaired in the flies with forelegs surgically removed. The time to puparium formation and to adult emergence of the larvae on the food with 70 mmol/L lactic acid was prolonged by 1.42 d and 1.17 d, respectively, and the larval survival rate decreased by 36.0%, as compared to those of the control. Lactic acid induced intestinal dysplasia with the increased number of mitotic cells. 【Conclusion】 Female adults of D. melanogaster avoid laying eggs on the food covered with metabolites of L. brevis by anaerobic fermentation. The metabolite lactic acid produced under anaerobic condition, which is detected by flies mainly through taste perception, induces the oviposition avoidance of D. melanogaster, thus promoting the development and the survival rate of their progeny.

Effects of sublethal doses of imidacloprid on the expression of immune and detoxification related genes and the activities of immune and detoxification related enzymes in house and field bees of Apis mellifera ligustica

HOU Meng-Shang, YU Tian-Tian, QIU Yuan-Mei, LI Yun-Xian, LI Zhi-Guo, SU Song-Kun

2019, 62(12): 1409-1416. doi:10.16380/j.kcxb.2019.12.007

Abstract ( 46 )

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【Aim】 Imidacloprid is one of the widely used neonicotinoid insecticides. Studies indicated that sublethal doses of imidacloprid affect the larval development of honeybees and the foraging and learning behaviors of adult honeybees. This study aims to investigate the effects of sublethal doses of imidacloprid on the expression of immune and detoxification related genes and the activities of immune and detoxification related enzymes in house bees (1 day-old adults) and field bees (21 day-old adults) of Apis mellifera ligustica, so as to provide a scientific basis for the maintenance of honeybee health. 【Methods】 The 1 and 21 day-old adults of A. m. ligustica were fed with 50% (w/v) sucrose solution containing 0.1 ng/μL of imidacloprid ad libitum, the survival rates at different time after treatment were determined. The expression levels of PPOA3 (GenBank accession no.: GB43738), CYP450 6a2 (GenBank accession no.: GB49876), ABA (GenBank accession no.: GB18323), GLD (GenBank accession no.: GB43007) in the adult bees at 6 d after treatment were detected by real-time quantitative PCR, and the content of cytochrome P450 (CYP450) and the activity of polyphenol oxidase (PPO) in them were determined by double antibody one-step sandwich enzyme-linked immunosorbent assay. 【Results】 After the 1 day-old and 21 day-old adult bees of A. m. ligustica were continuously fed with 50% sucrose solution containing 0.1 ng/μL imidacloprid for 6 d, their survival rates showed no significant difference from the control ［fed with 50% (w/v) sucrose containing 0.1 ng/μL of acetone］ (P>0.05). After the 1 and 21 dayold adult bees of A. m. ligustica were continuously fed with 50% sucrose solution containing 0.1 ng/μL imidacloprid for 9 d, the survival rate of the 1 day-old adult bees showed no significant difference from the control, while the survival rate of the 21 day-old adult bees showed significant difference from the control. The expression levels of PPOA3, CYP450 6a2, ABA and GLD, the CYP450 content and the PPO activity in 1 day-old adult bees exposed to 0.1 ng/μL imidacloprid for 6 d were significantly downregulated as compared to those in the control. The expression levels of CYP450 6a2, ABA, and GLD and the PPO activity in 21 day-old adult bees exposed to 0.1 ng/μL imidacloprid for 6 d were significantly downregulated, while the expression levels of PPOA3 and the CYP450 content were significantly elevated as compared to those in the control group. 【Conclusion】 Sublethal doses of imidacloprid affect the expression of immune and detoxification related genes and the activities of immune and detoxification related enzymes in both house and field bees of A. m. ligustica. The short-term stress of imidacloprid has no significant effect on the survival of the house and field bees of A. m. ligustica, but long-term stress may affect their survival.

Effects of temperature on the growth, development and reproduction of the tomato leaf miner, Tuta absoluta (Lepidoptera: Gelechiidae)

LI Dong, LI Xiao-Wei, MA Lin, FU Kai-Yun, DING Xin-Hua, GUO Wen-Chao, LU Yao-Bin

2019, 62(12): 1417-1426. doi:10.16380/j.kcxb.2019.12.008

Abstract ( 68 )

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【Aim】 The tomato leaf miner, Tuta absoluta, is a devastating invasive alien pest worldwide, causing severe damage to global tomato industry. In this study, the effects of temperature on the growth, development and reproduction of T. absoluta were studied in order to provide the basic information for prediction of its potential distribution and population dynamics in newly invaded areas. 【Methods】 The developmental duration, survival rate and population growth parameters of T. absoluta on tomato leaves under laboratory conditions were investigated, and the lower temperature threshold, upper temperature threshold, optimum temperature, effective accumulative temperature and occurrence generation were determined by using models based on developmental rates or population growth parameters. 【Results】 Within the constant temperatures ranging from 15 to 30℃, the duration of different developmental stages of T. absoluta shortened as the temperature rose. At 25℃, the survival rate at the larval and entire immature stages, the total fecundity, the net reproductive rate, the intrinsic rate of natural increase and the finite rate of increase were all the greatest. At 35℃, the survival rate of eggs decreased sharply to 11%, and the larvae could not finish development. The effective accumulative temperatures of egg, larval, pupal, entire immature stages and the whole generation were 104.17, 232.59, 129.87, 434.78 and 526.32 degree-days, respectively. T. absoluta could have four to five generations per year in Yining County and Qapqal Xibe Autonomous County, Xinjiang. Thermal requirement parameters estimated by the model based on the relationship between the developmental rate and temperature showed different results from those by the model based on the relationship between the intrinsic rate of natural increase and temperature. The lower temperature threshold, upper temperature threshold and optimum temperature based on the intrinsic rate of natural increase were 12.46, 30.40 and 27.36℃, respectively. 【Conclusion】 The range of adaptive temperature for the invasive T. absoluta population in Xinjiang is wide, suggesting that it has a high diffusion threat to most parts of China.

Fitness of Aenasius bambawalei (Hymenoptera: Encyrtidae) on a new host species

HUANG Jun, ZHI Fu-Ying, LU Yao-Bin

2019, 62(12): 1427-1434. doi:10.16380/j.kcxb.2019.12.009

Abstract ( 35 )

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【Aim】 Aenasius bambawalei (Hymenoptera: Encyrtidae) is an accompanying parasitoid of the invasive mealybug, Phenacoccus solenopsis (Homoptera: Pseudococcidae), and it was known that this parasitic wasp only parasitizes the mealybug. However, we newly discovered that A. bambawalei can parasitize another alien invasive mealybug, P. solani (Homoptera: Pseudococcidae), in China. This study aims to determine the fitness of A. bambawalei on the new host species, so as to provide a scientific basis for the full development and utilization of the parasitoid in the future. 【Methods】 The fitness of A. bambawalei on P. solani of different developmental stages with potato as the host plant was determined in the laboratory, and the formation time of mummies, emergence time, longevity, hind tibia length, parasitism rate, emergence rate and offspring sex ratio of A. bambawalei adults on the above two host species under non-selective conditions were also investigated. 【Results】 A. bambawalei parasitized the female adults and the 2nd and 3rd instar nymphs of P. solani, but only emerged from the parasitized female adults. The most appropriate parasitiod-host ratios were 2∶15 and 2∶20 with P. solenopsis and P. solani used as the hosts of A. bambawalei, respectively. Host species showed no significant influence on the formation time of mummies and the emergence time of A. bambawalei, but significantly influenced the longevity of A. bambawalei. The longevity of A. bambawalei adults emerged from P. solenopsis was ca. 20 d longer than that emerged from P. solani. Moreover, the parasitism rate of A. bambawalei on P. solenopsis was higher than that on P. solani (54.0% vs. 25.3%), but the emergence rates of A. bambawalei on the two hosts showed no significant difference (both over 90%). The proportion of female wasps emerged from P. solenopsis was higher than the proportion of female wasps emerged from P. solani. 【Conclusion】 A. bambawalei can parasitize female adults and the 2nd and 3rd instar nymphs of P. solani, but only completes generation development on its female adults. A. bambawalei on P. solani shows a disadvantage in the longevity and individual female size compared with that on the more suitable host P. solenopsis.

Advances in aphid salivary protein research

SHANG Zhe-Ming, LIU De-Guang

2019, 62(12): 1435-1447. doi:10.16380/j.kcxb.2019.12.010

Abstract ( 64 )

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Aphids (Hemiptera: Aphididae), a group of important agricultural pests, ingest plant phloem sap and transmit plant viruses with piercing-sucking mouthparts. The outbreak of aphids often causes serious economic losses. In the long history of co-evolution, plants have established effective defense systems against the threat of aphids. In order to overcome these plant defenses, aphids also have developed sophisticated countermeasures. Among them, aphids secrete salivary proteins during the feeding process, which can modulate plant defenses and degrade plant secondary metabolites. Therefore, salivary proteins play a critical role in plant-aphid interactions. In this review, we summarized recent advances in the identification of aphid salivary proteins and the functional research of associated proteins, and brought forward the prospects about application of salivary proteins in aphid control and new directions for future research. Common methods used to identify and predict aphid salivary proteins include enzymatic activity assay of salivary proteins, proteomic analysis of aphid saliva, and transcriptomic and proteomic analysis of salivary glands. However, these methods all have their own advantages and disadvantages, and individual method may just reveal partial real information of the whole aphid secretome. The combination of different techniques can provide more realistic and detailed information. Aphid salivary proteins can be classified into various categories including detoxifying enzymes, protective enzymes, hydrolases, binding domain proteins, effector proteins of unknown function categories and so on. Aphid salivary proteins have multiple functions, such as participating in salivary sheath formation, inducing or repressing plant defenses, promoting aphid feeding and enhancing aphid fecundity. Silencing aphid salivary protein coding genes via RNAi technology can significantly affect feeding behaviors, and decrease aphid survival rate, fecundity and fitness. Therefore, aphid salivary proteins are ideal targets for manipulation in aphid control. Now, in several crops, some effective aphid-resistant lines, which can target salivary protein coding genes, have been established, via the HIGS (host-induced gene silencing) technique, and they have showed good application prospects. According to the present studies, it is urgent to analyze aphid secretomes with combination of multiple Omic techniques. There is still a serious lack of research on the specific functions of various salivary proteins. It is necessary to explore the functions and related molecular mechanisms of salivary proteins of aphids from multiple dimensions, such as aphids, plants and the interactions between them, so as to lay a foundation for the development of new aphid control strategies based on the regulation of salivary proteins in aphids.

Plant-mediated RNA interference in insect pests

FU Shu, LIU Zhao-Xia, CHEN Jin-Zhi, SUN Geng-Xiao, SUN Cui-Ying, YANG Guang

2019, 62(12): 1448-1468. doi:10.16380/j.kcxb.2019.12.011

Abstract ( 59 )

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Insect pest control by plant-mediated RNAi has received extensive attention in the recent decade. The process involves two steps: the first is the expression, transport and storage of the dsRNAs of target genes in a plant, and the second is that the expression of target gene in the pest is specifically inhibited after the pest feeds on this plant. So far, plant-mediated RNAi has been focused on Coleoptera, Lepidoptera and Homoptera pests, causing the abnormal growth and development, reduced fecundity, and mortality of insect pests, and even the abnormal growth and development of their offspring. There are many factors affecting the efficacy of plant-mediated RNAi for pest control, including the selection of target gene/locus, the length of dsRNA, dsRNA expression vector and the transformation method of plant. Plant-mediated RNAi for pest control is still facing some challenges, such as the ecological safety of transgenic plant and the potential off-target effect of RNAi. With the development of this technology, it could become a new strategy for pest control.

Biology, ecology and integrated management of the potato tuber moth, Phthorimaea operculella (Lepidoptera: Gelechiidae)

YAN Jun-Jie, ZHANG Meng-Di, GAO Yu-Lin

2019, 62(12): 1469-1482. doi:10.16380/j.kcxb.2019.12.012

Abstract ( 83 )

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The potato tuber moth (PTM), Phthorimaea operculella, also known as tobacco leafminer, is a worldwide agricultural pest of Solanaceae crops, especially destructive to potatoes. It originated from the northern region of Central and South America and now has been distributed in more than 100 countries in Asia, Europe, North America, Africa and other regions. At present, this pest occurs in southern potato production areas in China, especially in Yunnan, Sichuan and Guizhou provinces, and the moth is likely to spread to other potato producing areas with climate change. P. operculella reproduces mainly by sexual reproduction and occasionally by parthenogenesis. Its larvae burrow into cavities in potato leaves and tubers. There is no sexual dimorphism in the newly hatched larvae; however, the sex of the 4th instar larva, pupa and adult can be distinguished based on the morphological characteristics. The number of generations of PTM depends on local agricultural climatic conditions, ranging from 2-12 generations per year. P. operculella has high adaptability to temperature fluctuations, and it is prone to large outbreaks in dry and hot years. Early prevention and control mainly focus on agricultural control measures such as selecting resistant varieties, deep seeding and irrigation. Chemical control is still the main way to control PTM. However, due to the widespread use of chemical pesticides, this insect has developed resistance to organophosphates, pyrethroids and other insecticides. In order to reduce the use of chemical pesticides and to slow down the development of pesticide resistance, a variety of natural enemies and insect pathogenic microorganisms have been found and screened for the control of PTM. The sex pheromone of PTM with (E4, Z7)tridecadienyl acetate and (E4, Z7, Z10)tridecacenyl acetate as the main components are effective for monitoring and control of PTM. Eucalyptus, ruffle mint and other plantderived compounds can inhibit the PTM oviposition. Transgenic insect-resistant potatoes and sterile insect technique have also become new methods for the prevention and control of PTM. Previous studies have revealed that it is difficult to achieve the ideal control effect by using a single biological control method, so integrating chemical substances, natural enemies and pathogenic microorganisms compatible with biological control technology is an important trend to effectively control the PTM population. In this article we reviewed the research progresses of the occurrence and damage and the comprehensive prevention and control technology of PTM at home and abroad systematically, hoping to provide reference sources for the sustainable management of PTM.

Contents of Vol. 62 Issue 12

2019, 62(12): 1483-1483.

Abstract ( 32 )

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General content of Volume 62(1-12)

2019, 62(12): 1483-1483.

Abstract ( 0 )

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