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Lin XY, Zheng Y, Shen Y, Li DS. Olfactory preference of the litchi fruit borer for oviposition on two litchi varieties. PEST MANAGEMENT SCIENCE 2024; 80:4714-4724. [PMID: 38779954 DOI: 10.1002/ps.8186] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2023] [Revised: 04/29/2024] [Accepted: 05/08/2024] [Indexed: 05/25/2024]
Abstract
BACKGROUND The litchi fruit borer Conopomorpha sinensis Bradley is a major destructive pest of litchi and longan plants in China, India and South East Asia. Given its strong olfactory-based oviposition behaviour, interfering with the chemical communication between this insect pest and its host plant may serve as a potential control strategy. However, the chemical compounds associated with its egg-laying behaviour remain poorly understood. RESULTS In this study, we investigated the olfactory preference of female C. sinensis for oviposition on intact mature fruits of the Feizixiao (FZX) and Guiwei (GW) varieties. Results showed that female C. sinensis preferred to lay eggs on FZX compared with GW fruits, and this preference was olfactory-induced. In addition, we identified differences in the chemical composition of the volatile blend and proportions between FZX and GW fruits, with terpenes being the main volatile components contributing to this divergence. Compounds that induced electrophysiological activity in female borers were subsequently screened from FZX. d-Limonene exhibited the strongest oviposition attraction among four candidates. Furthermore, this compound served as a volatile olfactory cue for recognition and orientation in female C. sinensis. CONCLUSION The results of this study provide a deeper understanding of the olfactory preferences of female C. sinensis for oviposition on specific litchi varieties. © 2024 Society of Chemical Industry.
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Affiliation(s)
- Xian-Yu Lin
- Institute of Plant Protection, Guangdong Academy of Agricultural Sciences, Key Laboratory of Green Prevention and Control on Fruits and Vegetables in South China Ministry of Agriculture and Rural Affairs, Guangdong Provincial Key Laboratory of High Technology for Plant Protection, Guangzhou, China
| | - Yuan Zheng
- Institute of Plant Protection, Guangdong Academy of Agricultural Sciences, Key Laboratory of Green Prevention and Control on Fruits and Vegetables in South China Ministry of Agriculture and Rural Affairs, Guangdong Provincial Key Laboratory of High Technology for Plant Protection, Guangzhou, China
| | - Ying Shen
- Institute of Plant Protection, Guangdong Academy of Agricultural Sciences, Key Laboratory of Green Prevention and Control on Fruits and Vegetables in South China Ministry of Agriculture and Rural Affairs, Guangdong Provincial Key Laboratory of High Technology for Plant Protection, Guangzhou, China
| | - Dun-Song Li
- Institute of Plant Protection, Guangdong Academy of Agricultural Sciences, Key Laboratory of Green Prevention and Control on Fruits and Vegetables in South China Ministry of Agriculture and Rural Affairs, Guangdong Provincial Key Laboratory of High Technology for Plant Protection, Guangzhou, China
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2
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Zhang J, Yu Y, Qian X, Zhang X, Li X, Sun X. Recent Advances in the Specialized Metabolites Mediating Resistance to Insect Pests and Pathogens in Tea Plants ( Camellia sinensis). PLANTS (BASEL, SWITZERLAND) 2024; 13:323. [PMID: 38276780 PMCID: PMC10818678 DOI: 10.3390/plants13020323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 01/11/2024] [Accepted: 01/17/2024] [Indexed: 01/27/2024]
Abstract
Tea is the second most popular nonalcoholic beverage consumed in the world, made from the buds and young leaves of the tea plants (Camellia sinensis). Tea trees, perennial evergreen plants, contain abundant specialized metabolites and suffer from severe herbivore and pathogen attacks in nature. Thus, there has been considerable attention focusing on investigating the precise function of specialized metabolites in plant resistance against pests and diseases. In this review, firstly, the responses of specialized metabolites (including phytohormones, volatile compounds, flavonoids, caffeine, and L-theanine) to different attacks by pests and pathogens were compared. Secondly, research progress on the defensive functions and action modes of specialized metabolites, along with the intrinsic molecular mechanisms in tea plants, was summarized. Finally, the critical questions about specialized metabolites were proposed for better future research on phytohormone-dependent biosynthesis, the characteristics of defense responses to different stresses, and molecular mechanisms. This review provides an update on the biological functions of specialized metabolites of tea plants in defense against two pests and two pathogens.
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Affiliation(s)
| | | | | | | | | | - Xiaoling Sun
- Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310008, China; (J.Z.); (Y.Y.); (X.Q.); (X.Z.); (X.L.)
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3
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Osinde C, Sobhy IS, Wari D, Dinh ST, Hojo Y, Osibe DA, Shinya T, Tugume AK, Nsubuga AM, Galis I. Comparative analysis of sorghum (C4) and rice (C3) plant headspace volatiles induced by artificial herbivory. PLANT SIGNALING & BEHAVIOR 2023; 18:2243064. [PMID: 37585707 PMCID: PMC10730142 DOI: 10.1080/15592324.2023.2243064] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Revised: 07/24/2023] [Accepted: 07/25/2023] [Indexed: 08/18/2023]
Abstract
Acute stress responses include release of defensive volatiles from herbivore-attacked plants. Here we used two closely related monocot species, rice as a representative C3 plant, and sorghum as a representative C4 plant, and compared their basal and stress-induced headspace volatile organic compounds (VOCs). Although both plants emitted similar types of constitutive and induced VOCs, in agreement with the close phylogenetic relationship of the species, several mono- and sesquiterpenes have been significantly less abundant in headspace of sorghum relative to rice. Furthermore, in spite of generally lower VOC levels, some compounds, such as the green leaf volatile (Z)-3-hexenyl acetate and homoterpene DMNT, remained relatively high in the sorghum headspace, suggesting that a separate mechanism for dispersal of these compounds may have evolved in this plant. Finally, a variable amount of several VOCs among three sorghum cultivars of different geographical origins suggested that release of VOCs could be used as a valuable resource for the increase of sorghum resistance against herbivores.
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Affiliation(s)
- Cyprian Osinde
- Department of Plant Sciences, Microbiology and Biotechnology Makerere University, Kampala, Uganda
- Institute of Plant Science and Resources, Okayama University, Kurashiki, Japan
| | - Islam S. Sobhy
- Institute of Plant Science and Resources, Okayama University, Kurashiki, Japan
- Department of Plant Protection, Faculty of Agriculture, Suez Canal University, Ismailia, Egypt
- School of Biosciences, Cardiff University, Cardiff, UK
| | - David Wari
- Institute of Plant Science and Resources, Okayama University, Kurashiki, Japan
| | - Son Truong Dinh
- Institute of Plant Science and Resources, Okayama University, Kurashiki, Japan
- Faculty of Biotechnology, Vietnam National University of Agriculture, Hanoi, Vietnam
| | - Yuko Hojo
- Institute of Plant Science and Resources, Okayama University, Kurashiki, Japan
| | - Dandy A. Osibe
- Institute of Plant Science and Resources, Okayama University, Kurashiki, Japan
- Department of Plant Science and Biotechnology, University of Nigeria, Nsukka, Nigeria
| | - Tomonori Shinya
- Institute of Plant Science and Resources, Okayama University, Kurashiki, Japan
| | - Arthur K. Tugume
- Department of Plant Sciences, Microbiology and Biotechnology Makerere University, Kampala, Uganda
| | - Anthony M. Nsubuga
- Department of Plant Sciences, Microbiology and Biotechnology Makerere University, Kampala, Uganda
| | - Ivan Galis
- Institute of Plant Science and Resources, Okayama University, Kurashiki, Japan
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Lun X, Xu X, Zhang Y, Zhang R, Cao Y, Zhang X, Jin M, Zhang Z, Zhao Y. An Antennae-Enriched Odorant-Binding Protein EonuOBP43 Mediate the Behavioral Response of the Tea Green Leafhopper, Empoasca onukii Matsuda to the Host and Nonhost Volatiles. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2023; 71:20000-20010. [PMID: 38059819 DOI: 10.1021/acs.jafc.3c07144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/08/2023]
Abstract
Olfaction is crucial for Empoasca onukii Matsuda to recognize odors from the host and nonhost plants, and it has been proposed that odorant binding proteins are directly required for odorant discrimination and represent potential targets of interest for pest control. Here, we cloned EonuOBP43 and expressed the recombinant EonuOBP43 protein. Furthermore, competitive fluorescence binding assays with 19 ligands indicated that terpenoids and alkanes showed a relatively higher than for other classes of chemicals. Additionally, ligand docking and site-directed mutagenesis results revealed that seven hydrophobic residues, including Val-86, Met-89, Phe-90, Ile-104, Ile-105, Leu-130, and Val-134, played a key role in the binding of EonuOBP43 to plant volatiles. In olfactometer tests, E. onukii were significantly attracted to α-farnesene and repelled to β-caryophyllene, and dsOBP43 treated adult lost response to α-farnesene and β-caryophyllene. In summary, our results demonstrated that EonuOBP43 may function as a carrier in the process of sensing plant compounds of E. onukii.
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Affiliation(s)
- Xiaoyue Lun
- Shandong Agricultural University, Tai'an 271018, China
| | - Xiuxiu Xu
- Tea Research Institute, Shandong Academy of Agricultural Sciences, 202 Gongye North Road, Jinan 250100, China
| | - Yu Zhang
- Shandong Agricultural University, Tai'an 271018, China
| | - Ruirui Zhang
- Shandong Agricultural University, Tai'an 271018, China
| | - Yan Cao
- Shandong Agricultural University, Tai'an 271018, China
| | | | - Meina Jin
- Shandong Agricultural University, Tai'an 271018, China
| | | | - Yunhe Zhao
- Shandong Agricultural University, Tai'an 271018, China
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Zhang R, Lun X, Zhang Y, Zhao Y, Xu X, Zhang Z. Characterization of Ionotropic Receptor Gene EonuIR25a in the Tea Green Leafhopper, Empoasca onukii Matsuda. PLANTS (BASEL, SWITZERLAND) 2023; 12:2034. [PMID: 37653951 PMCID: PMC10223087 DOI: 10.3390/plants12102034] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Revised: 05/14/2023] [Accepted: 05/15/2023] [Indexed: 09/02/2023]
Abstract
Ionotropic receptors (IRs) play a central role in detecting chemosensory information from the environment and guiding insect behaviors and are potential target genes for pest control. Empoasca onukii Matsuda is a major pest of the tea plant Camellia sinensis (L.) O. Ktze, and seriously influences tea yields and quality. In this study, the ionotropic receptor gene EonuIR25a in E. onukii was cloned, and the expression pattern of EonuIR25a was detected in various tissues. Behavioral responses of E. onukii to volatile compounds emitted by tea plants were determined using olfactometer bioassay and field trials. To further explore the function of EonuIR25a in olfactory recognition of compounds, RNA interference (RNAi) of EonuIR25a was carried out by ingestion of in vitro synthesized dsRNAs. The coding sequence (CDS) length of EonuIR25a was 1266 bp and it encoded a 48.87 kD protein. EonuIR25a was enriched in the antennae of E. onukii. E. onukii was more significantly attracted by 1-phenylethanol at a concentration of 100 µL/mL. Feeding with dsEonuIR25a significantly downregulated the expression level of EonuIR25a, after 3 h of treatment, which disturbed the behavioral responses of E. onukii to 1-phenylethanol at a concentration of 100 µL/mL. The response rate of E. onukii to 1-phenylethanol was significantly decreased after dsEonuIR25a treatment for 12 h. In summary, the ionotropic receptor gene EonuIR25a was highly expressed in the antennae of E. onukii and was involved in olfactory recognition of the tea plant volatile 1-phenylethanol. The present study may help us to use the ionotropic receptor gene as a target for the behavioral manipulation of E. onukii in the future.
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Affiliation(s)
- Ruirui Zhang
- College of Horticulture Science and Engineering, Shandong Agricultural University, Tai’an 271000, China; (R.Z.)
| | - Xiaoyue Lun
- College of Horticulture Science and Engineering, Shandong Agricultural University, Tai’an 271000, China; (R.Z.)
| | - Yu Zhang
- College of Horticulture Science and Engineering, Shandong Agricultural University, Tai’an 271000, China; (R.Z.)
| | - Yunhe Zhao
- College of Horticulture Science and Engineering, Shandong Agricultural University, Tai’an 271000, China; (R.Z.)
| | - Xiuxiu Xu
- Tea Research Institute, Shandong Academy of Agricultural Science, Ji’nan 250100, China
| | - Zhengqun Zhang
- College of Horticulture Science and Engineering, Shandong Agricultural University, Tai’an 271000, China; (R.Z.)
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Frontini A, De Bellis L, Luvisi A, Blando F, Allah SM, Dimita R, Mininni C, Accogli R, Negro C. The Green Leaf Volatile (Z)-3-Hexenyl Acetate Is Differently Emitted by Two Varieties of Tulbaghia violacea Plants Routinely and after Wounding. PLANTS (BASEL, SWITZERLAND) 2022; 11:3305. [PMID: 36501344 PMCID: PMC9739665 DOI: 10.3390/plants11233305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 11/19/2022] [Accepted: 11/26/2022] [Indexed: 06/17/2023]
Abstract
While studying aromas produced by the edible flowers of Tulbaghia violacea, we noticed a different production of (Z)-3-Hexenyl acetate (a green-leaf volatile, GLV) by purple (var. ‘Violacea’) and white (var. ‘Alba’) flowers. The white Tulbaghia flowers constantly emits (Z)-3-Hexenyl acetate, which is instead produced in a lower amount by the purple-flowered variety. Thus, we moved to analyze the production of (Z)-3-Hexenyl acetate by whole plants of the two varieties by keeping them confined under a glass bell for 5 h together with a SPME (Solid Phase Micro Extraction) fiber. Results show that six main volatile compounds are emitted by T. violacea plants: (Z)-3-Hexenyl acetate, benzyl alcohol, nonanal, decanal, (Z)-3-Hexenyl-α-methylbutyrate, and one unknown compound. By cutting at half-height of the leaves, the (Z)-3-Hexenyl acetate is emitted in high quantities from both varieties, while the production of (Z)-3-Hexenyl-α-methylbutyrate increases. (Z)-3-Hexenyl acetate is a GLV capable of stimulating plant defenses, attracting herbivores and their natural enemies, and it is also involved in plant-to-plant communication and defense priming. Thus, T. violacea could represent a useful model for the study of GLVs production and a ‘signal’ plant capable of stimulating natural defenses in the neighboring plants.
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Affiliation(s)
- Alessandro Frontini
- Department of Biological and Environmental Sciences and Technologies (DiSTeBA), Salento University, Via Prov.le Lecce-Monteroni, 73100 Lecce, Italy
| | - Luigi De Bellis
- Department of Biological and Environmental Sciences and Technologies (DiSTeBA), Salento University, Via Prov.le Lecce-Monteroni, 73100 Lecce, Italy
| | - Andrea Luvisi
- Department of Biological and Environmental Sciences and Technologies (DiSTeBA), Salento University, Via Prov.le Lecce-Monteroni, 73100 Lecce, Italy
| | - Federica Blando
- Institute of Sciences of Food Production (ISPA), National Research Council (CNR), Research Unit of Lecce, Via Prov.le Lecce-Monteroni, 73100 Lecce, Italy
| | - Samar Min Allah
- Department of Biological and Environmental Sciences and Technologies (DiSTeBA), Salento University, Via Prov.le Lecce-Monteroni, 73100 Lecce, Italy
| | - Rosanna Dimita
- Department of Biological and Environmental Sciences and Technologies (DiSTeBA), Salento University, Via Prov.le Lecce-Monteroni, 73100 Lecce, Italy
| | - Carlo Mininni
- Ortogourmet Società Agricola S.r.l., S.C. 14 Madonna delle Grazie, 74014 Laterza, Italy
| | - Rita Accogli
- Department of Biological and Environmental Sciences and Technologies (DiSTeBA), Salento University, Via Prov.le Lecce-Monteroni, 73100 Lecce, Italy
| | - Carmine Negro
- Department of Biological and Environmental Sciences and Technologies (DiSTeBA), Salento University, Via Prov.le Lecce-Monteroni, 73100 Lecce, Italy
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Yao Q, Wang M, Chen Z. The Relative Preference of Empoasca onukii (Hemiptera: Cicadellidae) for Oviposition on Twenty-Four Tea Cultivars. JOURNAL OF ECONOMIC ENTOMOLOGY 2022; 115:1521-1530. [PMID: 36029237 DOI: 10.1093/jee/toac130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2022] [Indexed: 06/15/2023]
Abstract
The tea green leafhopper, Empoasca onukii Matsuda (Hemiptera: Cicadellidae) is currently one of the most threatening pests of tea production in China. Several approaches have been used to identify the resistance of different tea cultivars to this important tea pest. However, relatively limited information has been documented about its oviposition preferences. This study aimed to elucidate the preferential oviposition of E. onukii among 24 tea cultivars. Towards this objective, a multi-selective test for E. onukii oviposition was conducted in the laboratory, and the egg densities of E. onukii on 24 varieties were also surveyed in plantations at different time periods during the tea plant growing season in 2019. There was a significant difference in E. onukii egg densities among the 24 cultivars studied in both laboratory tests and the field investigations. Moreover, there was a positive correlation between the laboratory and field data for the number of eggs laid per cultivar. According to the laboratory and field evaluations, 2 cultivars were identified as very-susceptible for E. onukii oviposition, while another 5 cultivars were assigned as susceptible, 9 cultivars were classified as resistant and 2 cultivars were identified as very-resistant, respectively. This information on the oviposition preference for E. onukii on different cultivars could be used as a selection parameter for further breeding of leafhopper-resistant tea cultivars.
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Affiliation(s)
- Qi Yao
- Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310008, China
- College of Plant Science & Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Manqun Wang
- College of Plant Science & Technology, Huazhong Agricultural University, Wuhan 430070, China
| | - Zongmao Chen
- Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310008, China
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Qin H, Hong W, Qi Z, Hu Y, Shi R, Wang S, Wang Y, Zhou J, Mu D, Fu J, Sun T. A Temperature-Dependent Model for Tritrophic Interactions Involving Tea Plants, Tea Green Leafhoppers and Natural Enemies. INSECTS 2022; 13:insects13080686. [PMID: 36005311 PMCID: PMC9409375 DOI: 10.3390/insects13080686] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/27/2022] [Revised: 07/26/2022] [Accepted: 07/26/2022] [Indexed: 11/16/2022]
Abstract
The tea green leaf hopper, Empoasca onukii Matsuda, is a severe pest of tea plants. Volatile emissions from tea shoots infested by the tea green leafhopper may directly repel insect feeding or attract natural enemies. Many studies have been conducted on various aspects of the tritrophic relationship involving tea plants, tea green leafhoppers and natural enemies. However, mathematic models which could explain the dynamic mechanisms of this tritrophic interaction are still lacking. In the current work, we constructed a realistic and stochastic model with temperature-dependent features to characterize the tritrophic interactions in the tea agroecosystem. Model outputs showed that two leafhopper outbreaks occur in a year, with their features being consistent with field observations. Simulations showed that daily average effective accumulated temperature (EAT) might be an important metric for outbreak prediction. We also showed that application of slow-releasing semiochemicals, as either repellents or attractants, may be highly efficacious for pest biocontrol and can significantly increase tea yields. Furthermore, the start date of applying semiochemicals can be optimized to effectively increase tea yields. The current model qualitatively characterizes key features of the tritrophic interactions and provides critical insight into pest control in tea ecosystems.
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Affiliation(s)
- Huaguang Qin
- The Province Key Laboratory of the Biodiversity Study and Ecology Conservation in Southwest Anhui, School of Life Sciences, Anqing Normal University, Anqing 246133, China; (H.Q.); (W.H.); (Z.Q.); (Y.H.); (R.S.); (S.W.); (Y.W.); (D.M.)
| | - Wuxuan Hong
- The Province Key Laboratory of the Biodiversity Study and Ecology Conservation in Southwest Anhui, School of Life Sciences, Anqing Normal University, Anqing 246133, China; (H.Q.); (W.H.); (Z.Q.); (Y.H.); (R.S.); (S.W.); (Y.W.); (D.M.)
| | - Zehua Qi
- The Province Key Laboratory of the Biodiversity Study and Ecology Conservation in Southwest Anhui, School of Life Sciences, Anqing Normal University, Anqing 246133, China; (H.Q.); (W.H.); (Z.Q.); (Y.H.); (R.S.); (S.W.); (Y.W.); (D.M.)
| | - Yinghong Hu
- The Province Key Laboratory of the Biodiversity Study and Ecology Conservation in Southwest Anhui, School of Life Sciences, Anqing Normal University, Anqing 246133, China; (H.Q.); (W.H.); (Z.Q.); (Y.H.); (R.S.); (S.W.); (Y.W.); (D.M.)
| | - Rui Shi
- The Province Key Laboratory of the Biodiversity Study and Ecology Conservation in Southwest Anhui, School of Life Sciences, Anqing Normal University, Anqing 246133, China; (H.Q.); (W.H.); (Z.Q.); (Y.H.); (R.S.); (S.W.); (Y.W.); (D.M.)
| | - Shuyuan Wang
- The Province Key Laboratory of the Biodiversity Study and Ecology Conservation in Southwest Anhui, School of Life Sciences, Anqing Normal University, Anqing 246133, China; (H.Q.); (W.H.); (Z.Q.); (Y.H.); (R.S.); (S.W.); (Y.W.); (D.M.)
| | - Yuxi Wang
- The Province Key Laboratory of the Biodiversity Study and Ecology Conservation in Southwest Anhui, School of Life Sciences, Anqing Normal University, Anqing 246133, China; (H.Q.); (W.H.); (Z.Q.); (Y.H.); (R.S.); (S.W.); (Y.W.); (D.M.)
| | - Jianping Zhou
- Wanxinan Products Quality Supervision and Testing Center, Anqing 246052, China;
| | - Dan Mu
- The Province Key Laboratory of the Biodiversity Study and Ecology Conservation in Southwest Anhui, School of Life Sciences, Anqing Normal University, Anqing 246133, China; (H.Q.); (W.H.); (Z.Q.); (Y.H.); (R.S.); (S.W.); (Y.W.); (D.M.)
| | - Jianyu Fu
- Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou 310008, China
- Correspondence: (J.F.); (T.S.)
| | - Tingzhe Sun
- The Province Key Laboratory of the Biodiversity Study and Ecology Conservation in Southwest Anhui, School of Life Sciences, Anqing Normal University, Anqing 246133, China; (H.Q.); (W.H.); (Z.Q.); (Y.H.); (R.S.); (S.W.); (Y.W.); (D.M.)
- Correspondence: (J.F.); (T.S.)
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Li H, Wang Z, Han K, Guo M, Zou Y, Zhang W, Ma W, Hua H. Cloning and functional identification of a Chilo suppressalis-inducible promoter of rice gene, OsHPL2. PEST MANAGEMENT SCIENCE 2020; 76:3177-3187. [PMID: 32336018 DOI: 10.1002/ps.5872] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Revised: 03/11/2020] [Accepted: 04/26/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Promoters play a key role in driving insect-resistant genes during breeding of transgenic plants. In current transgenic procedures for breeding rice resistance to striped stem borer (Chilo suppressalis Walker, SSB), the constitutive promoter is used to drive the insect-resistant gene. To reduce the burden of constitutive promoters on plant growth, isolation and identification of insect-inducible promoters are particularly important. However, few promoters are induced specifically by insect feeding. RESULTS We found rice hydroperoxide lyase gene (OsHPL2) (LOC_Os02g12680) was upregulated after feeding by SSB. We subsequently cloned the promoter of OsHPL2 and analysed its expression pattern using the β-glucuronidase (GUS) reporter gene. Histochemical assays and quantitative analyses of GUS activity confirmed that P HPL2 :GUS was activated by SSB, but did not respond to brown planthopper (Nilaparvata lugens Stål, BPH) infestation, mechanical wounding or phytohormone treatments. A series of 5' truncated assays were conducted and three positive regulatory regions (-1452 to -1213, -903 to -624, and -376 to -176) induced by SSB infestation were identified. P2R123-min 35S and P2TR2-min 35S promoters linked with cry1C of transgenic plants showed the highest levels of Cry1C protein expression and SSB larval mortality. CONCLUSION We identified an SSB-inducible promoter and three positive internal regions. Transgenic rice plants with the OsHPL2 promoter and its positive regions driving cry1C exhibited the expected larvicidal effect on SSB. Our study is the first report of an SSB-inducible promoter that could be used as a potential resource for breeding insect-resistant transgenic crops. © 2020 Society of Chemical Industry.
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Affiliation(s)
- Hanpeng Li
- National Key Laboratory of Crop Genetic Improvement, National Centre of Plant Gene Research, Huazhong Agricultural University, Wuhan, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Zhengjie Wang
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Kehong Han
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Mengjian Guo
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Yulan Zou
- College of Life Science, Huazhong Agricultural University, Wuhan, China
| | - Wei Zhang
- National Key Laboratory of Crop Genetic Improvement, National Centre of Plant Gene Research, Huazhong Agricultural University, Wuhan, China
| | - Weihua Ma
- National Key Laboratory of Crop Genetic Improvement, National Centre of Plant Gene Research, Huazhong Agricultural University, Wuhan, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Hongxia Hua
- National Key Laboratory of Crop Genetic Improvement, National Centre of Plant Gene Research, Huazhong Agricultural University, Wuhan, China
- College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
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10
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Bian L, Cai XM, Luo ZX, Li ZQ, Chen ZM. Foliage Intensity is an Important Cue of Habitat Location for Empoasca onukii. INSECTS 2020; 11:insects11070426. [PMID: 32659987 PMCID: PMC7412280 DOI: 10.3390/insects11070426] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 07/06/2020] [Accepted: 07/06/2020] [Indexed: 11/02/2022]
Abstract
For many herbivorous insects, vision is more important than olfaction in the prealighting stage of host habitat location. Tea leafhoppers, Empoasca onukii (Hemiptera, Cicadellidae), are serious pests that preferentially inhabit the tender leaves of tea plants across China. Here, we investigated whether tea leafhoppers could distinguish foliage colors associated with different leaf ages and use this visual cue to guide suitable habitat location from short distances. Similar to honeybees, the adult E. onukii has an apposition type of compound eye, and each ommatidium has eight retinular cells, in which three spectral types of photoreceptors are distributed, with peak sensitivities at 356 nm (ultraviolet), 435 nm (blue), and 542 nm (green). Both changes in spectral intensity and hue of reflectance light of the host foliage were correlated with varying leaf age, and the intensity linearly decreased with increasing leaf age. Behavioral responses also showed that adult E. onukii could discriminate between the simulated colors of host foliage at different leaf ages without olfactory stimuli and selected the bright colors that strongly corresponded to those of tender leaves. The results suggest that, compared with the spectral composition (hue), the intensity of light reflectance from leaves at different ages is more important for adult leafhoppers when discriminating host foliage and could guide them to tender leaves at the top of tea shoots.
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Affiliation(s)
- Lei Bian
- Tea Research Institute, Chinese Academy of Agricultural Science, 9 Meiling South Road, Xihu District, Hangzhou 310008, China; (L.B.); (X.M.C.); (Z.X.L.); (Z.Q.L.)
- Key Laboratory of Tea Biology and Resource Utilization, Ministry of Agriculture, 9 Meiling South Road, Xihu District, Hangzhou 310008, China
| | - Xiao Ming Cai
- Tea Research Institute, Chinese Academy of Agricultural Science, 9 Meiling South Road, Xihu District, Hangzhou 310008, China; (L.B.); (X.M.C.); (Z.X.L.); (Z.Q.L.)
- Key Laboratory of Tea Biology and Resource Utilization, Ministry of Agriculture, 9 Meiling South Road, Xihu District, Hangzhou 310008, China
| | - Zong Xiu Luo
- Tea Research Institute, Chinese Academy of Agricultural Science, 9 Meiling South Road, Xihu District, Hangzhou 310008, China; (L.B.); (X.M.C.); (Z.X.L.); (Z.Q.L.)
- Key Laboratory of Tea Biology and Resource Utilization, Ministry of Agriculture, 9 Meiling South Road, Xihu District, Hangzhou 310008, China
| | - Zhao Qun Li
- Tea Research Institute, Chinese Academy of Agricultural Science, 9 Meiling South Road, Xihu District, Hangzhou 310008, China; (L.B.); (X.M.C.); (Z.X.L.); (Z.Q.L.)
- Key Laboratory of Tea Biology and Resource Utilization, Ministry of Agriculture, 9 Meiling South Road, Xihu District, Hangzhou 310008, China
| | - Zong Mao Chen
- Tea Research Institute, Chinese Academy of Agricultural Science, 9 Meiling South Road, Xihu District, Hangzhou 310008, China; (L.B.); (X.M.C.); (Z.X.L.); (Z.Q.L.)
- Key Laboratory of Tea Biology and Resource Utilization, Ministry of Agriculture, 9 Meiling South Road, Xihu District, Hangzhou 310008, China
- Correspondence: ; Tel.: +86-571-86650100
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11
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Hou BH, Tang H, Li JL, Meng X, Ouyang GC. Susceptibility of Selected Tea Shoots to Oviposition by Empoasca onukii (Hemiptera: Cicadellidae) and Feasibility of Egg Removal with Harvesting. INSECTS 2020; 11:insects11060338. [PMID: 32492822 PMCID: PMC7348997 DOI: 10.3390/insects11060338] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Revised: 05/29/2020] [Accepted: 05/29/2020] [Indexed: 12/02/2022]
Abstract
The Empoasca onukii (Hemiptera: Cicadellidae) female lays its eggs inside the epidermis of the tea plant shoots. This has led to speculation that shoot harvesting could represent a method of egg removal. To verify the validity of this hypothesis, we sought to determine which part of the shoot was used for the oviposition and how the value of the harvested shoot affects the cost of the egg removal. In this study, four tea cultivars were chosen to examine the preferences for the site of oviposition. In addition, a mathematical model was used to describe the correlation between the economic value of the selected shoot and eggs laid within the shoot. Our study revealed that the pest preferred the 3rd and 4th leaf order intervals of the shoot as the oviposition sites, and the oviposition preferences was dependent on the leaf order interval class across all tea cultivars. In addition, a significant negative exponential relationship was found between the economic value of the selected shoot and the percentage of the eggs laid within the shoot, indicating that egg removal through shoot harvesting was limited. The findings of this study could be used to better understand the role of shoot harvesting in egg removal and would provide new insights into the understanding of the incidence of this pest.
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Affiliation(s)
- Bo-Hua Hou
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Guangdong Institute of Applied Biological Resources, Guangzhou 510260, China;
- Correspondence: (B.-H.H.); (G.-C.O.); Tel.: +86-20-84199129 (B.-H.H.); +86-20-84199129 (G.-C.O.)
| | - Hao Tang
- Tea Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China; (H.T.); (J.-L.L.)
| | - Jian-Long Li
- Tea Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China; (H.T.); (J.-L.L.)
| | - Xiang Meng
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Guangdong Institute of Applied Biological Resources, Guangzhou 510260, China;
| | - Ge-Cheng Ouyang
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Guangdong Institute of Applied Biological Resources, Guangzhou 510260, China;
- Correspondence: (B.-H.H.); (G.-C.O.); Tel.: +86-20-84199129 (B.-H.H.); +86-20-84199129 (G.-C.O.)
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12
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Scott ER, Li X, Wei JP, Kfoury N, Morimoto J, Guo MM, Agyei A, Robbat A, Ahmed S, Cash SB, Griffin TS, Stepp JR, Han WY, Orians CM. Changes in Tea Plant Secondary Metabolite Profiles as a Function of Leafhopper Density and Damage. FRONTIERS IN PLANT SCIENCE 2020; 11:636. [PMID: 32547579 PMCID: PMC7272924 DOI: 10.3389/fpls.2020.00636] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2019] [Accepted: 04/24/2020] [Indexed: 05/12/2023]
Abstract
Insect herbivores have dramatic effects on the chemical composition of plants. Many of these induced metabolites contribute to the quality (e.g., flavor, human health benefits) of specialty crops such as the tea plant (Camellia sinensis). Induced chemical changes are often studied by comparing plants damaged and undamaged by herbivores. However, when herbivory is quantitative, the relationship between herbivore pressure and induction can be linearly or non-linearly density dependent or density independent, and induction may only occur after some threshold of herbivory. The shape of this relationship can vary among metabolites within plants. The tea green leafhopper (Empoasca onukii) can be a widespread pest on tea, but some tea farmers take advantage of leafhopper-induced metabolites in order to produce high-quality "bug-bitten" teas such as Eastern Beauty oolong. To understand the effects of increasing leafhopper density on tea metabolites important for quality, we conducted a manipulative experiment exposing tea plants to feeding by a range of E. onukii densities. After E. onukii feeding, we measured volatile and non-volatile metabolites, and quantified percent damaged leaf area from scanned leaf images. E. onukii density had a highly significant effect on volatile production, while the effect of leaf damage was only marginally significant. The volatiles most responsive to leafhopper density were mainly terpenes that increased in concentration monotonically with density, while the volatiles most responsive to leaf damage were primarily fatty acid derivatives and volatile phenylpropanoids/benzenoids. In contrast, damage (percent leaf area damaged), but not leafhopper density, significantly reduced total polyphenols, epigallocatechin gallate (EGCG), and theobromine concentrations in a dose-dependent manner. The shape of induced responses varied among metabolites with some changing linearly with herbivore pressure and some responding only after a threshold in herbivore pressure with a threshold around 0.6 insects/leaf being common. This study illustrates the importance of measuring a diversity of metabolites over a range of herbivory to fully understand the effects of herbivores on induced metabolites. Our study also shows that any increases in leafhopper density associated with climate warming, could have dramatic effects on secondary metabolites and tea quality.
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Affiliation(s)
- Eric R. Scott
- Department of Biology, Tufts University, Medford, MA, United States
- *Correspondence: Eric R. Scott, ;
| | - Xin Li
- Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, China
| | - Ji-Peng Wei
- Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, China
| | - Nicole Kfoury
- Department of Chemistry, Tufts University, Medford, MA, United States
| | - Joshua Morimoto
- Department of Chemistry, Tufts University, Medford, MA, United States
| | - Ming-Ming Guo
- Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, China
| | - Amma Agyei
- Department of Biology, Tufts University, Medford, MA, United States
| | - Albert Robbat
- Department of Chemistry, Tufts University, Medford, MA, United States
| | - Selena Ahmed
- Food and Health Lab, Department of Health and Human Development, Montana State University, Bozeman, MT, United States
| | - Sean B. Cash
- Friedman School of Nutrition and Policy, Tufts University, Medford, MA, United States
| | - Timothy S. Griffin
- Friedman School of Nutrition and Policy, Tufts University, Medford, MA, United States
| | - John R. Stepp
- Department of Anthropology, University of Florida, Gainsville, FL, United States
| | - Wen-Yan Han
- Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, China
- Wen-Yan Han,
| | - Colin M. Orians
- Department of Biology, Tufts University, Medford, MA, United States
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13
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Luo X, Chen Y, Chen C, Pu D, Tang X, Zhang H, Lu D, Mao J. Characterization of the complete mitochondrial genome of Empoasca sp. (Cicadellidae: Hemiptera). Mitochondrial DNA B Resour 2019. [DOI: 10.1080/23802359.2019.1579066] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Affiliation(s)
- Xi Luo
- Institute of Plant Protection, Sichuan Academy of Agricultural Sciences, Chengdu, Sichuan, P.R. China
| | - Yu Chen
- Institute of Plant Protection, Sichuan Academy of Agricultural Sciences, Chengdu, Sichuan, P.R. China
| | - Cheng Chen
- Institute of Plant Protection, Sichuan Academy of Agricultural Sciences, Chengdu, Sichuan, P.R. China
| | - Deqiang Pu
- Institute of Plant Protection, Sichuan Academy of Agricultural Sciences, Chengdu, Sichuan, P.R. China
| | - Xiaobo Tang
- Tea Research Institute, Sichuan Academy of Agricultural Sciences, Chengdu, Sichuan, P.R. China
| | - Hong Zhang
- Institute of Plant Protection, Sichuan Academy of Agricultural Sciences, Chengdu, Sichuan, P.R. China
| | - Daihua Lu
- Institute of Plant Protection, Sichuan Academy of Agricultural Sciences, Chengdu, Sichuan, P.R. China
| | - Jianhui Mao
- Institute of Plant Protection, Sichuan Academy of Agricultural Sciences, Chengdu, Sichuan, P.R. China
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14
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Xin Z, Cai X, Chen S, Luo Z, Bian L, Li Z, Ge L, Chen Z. A Disease Resistance Elicitor Laminarin Enhances Tea Defense against a Piercing Herbivore Empoasca (Matsumurasca) onukii Matsuda. Sci Rep 2019; 9:814. [PMID: 30692583 PMCID: PMC6349920 DOI: 10.1038/s41598-018-37424-7] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/11/2018] [Accepted: 11/30/2018] [Indexed: 11/26/2022] Open
Abstract
The tea plant (Camellia sinensis) suffers heavily from a harmful piercing pest, the tea green leafhopper (TLH) Empoasca (Matsumurasca) onukii Matsuda. In the present study, we studied the effect of an efficient elicitor of plant disease resistance, the β-1,3-glucan laminarin, on the induced defense against TLH in tea plants. Defense responses elicited by laminarin in tea include the activation of mitogen-activated protein kinases and WRKY, the burst of H2O2, salicylic acid, and abscisic acid, and the accumulation of direct-defense chemicals (including chitinase, phenylalanine ammonia lyase, callose, polyphenol oxidase, and flavonol synthase), as well as the production of volatile compounds. The laminarin-treated tea plants reduced the performance of TLH and enhanced the attractiveness to the egg parasitoid wasp of TLH, Stethynium empoascae Subba Rao. In the field experiment, laminarin application effectively reduced the number of TLH by attracting parasitoids. These results suggest that laminarin can induce protection against TLH by regulating signaling pathways in tea plant. Our study also proposes an environment friendly strategy for the integrated management of an economically important piercing pest.
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Affiliation(s)
- Zhaojun Xin
- Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, 310008, China.,Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agriculture, Hangzhou, 310008, China
| | - Xiaoming Cai
- Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, 310008, China.,Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agriculture, Hangzhou, 310008, China
| | - Shenglong Chen
- Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, 310008, China.,Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agriculture, Hangzhou, 310008, China
| | - Zongxiu Luo
- Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, 310008, China.,Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agriculture, Hangzhou, 310008, China
| | - Lei Bian
- Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, 310008, China.,Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agriculture, Hangzhou, 310008, China
| | - Zhaoqun Li
- Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, 310008, China.,Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agriculture, Hangzhou, 310008, China
| | - Lingang Ge
- Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, 310008, China.,Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agriculture, Hangzhou, 310008, China
| | - Zongmao Chen
- Tea Research Institute, Chinese Academy of Agricultural Sciences, Hangzhou, 310008, China. .,Key Laboratory of Tea Biology and Resources Utilization, Ministry of Agriculture, Hangzhou, 310008, China.
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15
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Zhou Q, Cheng X, Wang S, Liu S, Wei C. Effects of Chemical Insecticide Imidacloprid on the Release of C 6 Green Leaf Volatiles in Tea Plants (Camellia sinensis). Sci Rep 2019; 9:625. [PMID: 30679494 PMCID: PMC6345918 DOI: 10.1038/s41598-018-36556-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2018] [Accepted: 11/23/2018] [Indexed: 11/27/2022] Open
Abstract
Chemical insecticides are widely used for pest control worldwide. However, the impact of insecticides on indirect plant defense is seldom reported. Here, using tea plants and the pesticide imidacloprid, effects of chemical insecticides on C6-green leaf volatiles (GLVs) anabolism and release were investigated first time. Compared with the non-treated control plants, the treatment of imidacloprid resulted in the lower release amount of key GLVs: (Z)-3-hexenal, n-hexenal, (Z)-3-hexene-1-ol and (Z)-3-Hexenyl acetate. The qPCR analysis revealed a slight higher transcript level of the CsLOX3 gene but a significantly lower transcript level of CsHPL gene. Our results suggest that imidacloprid treatment can have a negative effect on the emission of GLVs due to suppressing the critical GLVs synthesis-related gene, consequently affecting plant indirect defense.
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Affiliation(s)
- Qiying Zhou
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 Changjiang West Road, Hefei, Anhui, 230036, China.,Henan Key Laboratory of Tea Plant Biology, Xinyang Normal University, 237 Nanhu Road, Xinyang, 464000, Henan, China.,Institute for Conservation and Utilization of Agro-Bioresources in Dabie Mountains, Xinyang Normal University, 237 Nanhu Road, Xinyang, 464000, Henan, China
| | - Xi Cheng
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 Changjiang West Road, Hefei, Anhui, 230036, China
| | - Shuangshuang Wang
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 Changjiang West Road, Hefei, Anhui, 230036, China
| | - Shengrui Liu
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 Changjiang West Road, Hefei, Anhui, 230036, China
| | - Chaoling Wei
- State Key Laboratory of Tea Plant Biology and Utilization, Anhui Agricultural University, 130 Changjiang West Road, Hefei, Anhui, 230036, China.
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16
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Bian L, Cai XM, Luo ZX, Li ZQ, Xin ZJ, Chen ZM. Design of an Attractant for Empoasca onukii (Hemiptera: Cicadellidae) Based on the Volatile Components of Fresh Tea Leaves. JOURNAL OF ECONOMIC ENTOMOLOGY 2018; 111:629-636. [PMID: 29361007 DOI: 10.1093/jee/tox370] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Indexed: 06/07/2023]
Abstract
The tea leafhopper, Empoasca onukii Matsuda, is a serious pest of the tea plant. E. onukii prefers to inhabit vigorously growing tender tea leaves. The host selection of E. onukii adults may be associated with plant volatile compounds (VOCs). We sought to identify potentially attractive VOCs from tea leaves at three different ages and test the behavioral responses of E. onukii adults to synthetic VOC blends in the laboratory and field to aid in developing an E. onukii adult attractant. In darkness, the fresh or mature tea leaves of less than 1-mo old could attract more leafhoppers than the mature branches (MB) that had many older leaves (leaf age >1 mo). Volatile analysis showed that the VOC composition of the fresh leaves was the same as that of the mature leaves, but linalool and indole were not at detectable levels in VOCs from the MB. Moreover, the mass ratio differed for each common volatile in the three types of tea leaves. When under competition with volatiles from the MB, the leafhoppers showed no significant tropism to each single volatile but could be attracted by the synthetic volatile blend imitating the fresh leaves. With the removal of some volatile components, the effective synthetic volatile blend was mixed with (Z)-3-hexen-1-ol, (Z)-3-hexenyl acetate, and linalool at a mass ratio of 0.6:23:12.6. These three volatiles may be the key components for the host selection of E. onukii adults and could be used as an attractant in tea gardens.
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Affiliation(s)
- Lei Bian
- Key Laboratory of Tea Biology and Resource Utilization, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Science, Xihu, Hangzhou, China
| | - Xiao-Ming Cai
- Key Laboratory of Tea Biology and Resource Utilization, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Science, Xihu, Hangzhou, China
| | - Zong-Xiu Luo
- Key Laboratory of Tea Biology and Resource Utilization, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Science, Xihu, Hangzhou, China
| | - Zhao-Qun Li
- Key Laboratory of Tea Biology and Resource Utilization, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Science, Xihu, Hangzhou, China
| | - Zhao-Jun Xin
- Key Laboratory of Tea Biology and Resource Utilization, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Science, Xihu, Hangzhou, China
| | - Zong-Mao Chen
- Key Laboratory of Tea Biology and Resource Utilization, Ministry of Agriculture, Tea Research Institute, Chinese Academy of Agricultural Science, Xihu, Hangzhou, China
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