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Li H, Liu J, Wang Q, Ma Y, Zhao W, Chen B, Price JH, Zhang D. Oleic acid triggers burial behavior in a termite population through an odorant binding protein. Insect Biochem Mol Biol 2024; 167:104090. [PMID: 38369269 DOI: 10.1016/j.ibmb.2024.104090] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2023] [Revised: 01/28/2024] [Accepted: 02/15/2024] [Indexed: 02/20/2024]
Abstract
Social insects maintain hygienic conditions through their social immunity behaviors. Among these behaviors, burial behavior of termites is central for protecting healthy individuals from corpses. Many factors trigger burial behavior, and it is generally believed that chemicals released by corpses, such as oleic acid, are the most important cues for triggering burial behavior in termites. However, the contribution of the olfactory system to this behavior remains unclear. Here we report an odorant binding protein (OBP) that transports oleic acid and triggers burial behavior in Coptotermes formosanus Shiraki. We demonstrated that CforOBP7 is highly expressed in the antennae of workers. Fluorescent competition binding experiments exhibited that CforOBP7 has a strong affinity for oleic acid. Furthermore, the antennal response to oleic acid was significantly reduced, and oleic acid-triggered burial behavior was also inhibited in CforOBP7-silenced termites. We conclude that CforOBP7 governs the burial behavior of C. formosanus triggered by oleic acid.
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Affiliation(s)
- Hongyue Li
- College of Advanced Agricultural Sciences, Zhejiang A&F University, Hangzhou, China
| | - Jiahan Liu
- College of Advanced Agricultural Sciences, Zhejiang A&F University, Hangzhou, China; College of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou, China
| | - Qian Wang
- College of Advanced Agricultural Sciences, Zhejiang A&F University, Hangzhou, China
| | - Yuanfei Ma
- College of Advanced Agricultural Sciences, Zhejiang A&F University, Hangzhou, China
| | - Weisong Zhao
- College of Advanced Agricultural Sciences, Zhejiang A&F University, Hangzhou, China
| | - Bosheng Chen
- College of Advanced Agricultural Sciences, Zhejiang A&F University, Hangzhou, China
| | - Jennifer Hackney Price
- School of Mathematical & Natural Sciences, New College of Interdisciplinary Arts & Sciences, Arizona State University, Phoenix, AZ, USA
| | - Dayu Zhang
- College of Advanced Agricultural Sciences, Zhejiang A&F University, Hangzhou, China.
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Xu D, Tong Y, Chen B, Li B, Wang S, Zhang D. The influence of first desaturase subfamily genes on fatty acid synthesis, desiccation tolerance and inter-caste nutrient transfer in the termite Coptotermes formosanus. Insect Mol Biol 2024; 33:55-68. [PMID: 37750189 DOI: 10.1111/imb.12877] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2022] [Accepted: 09/13/2023] [Indexed: 09/27/2023]
Abstract
Desaturase enzymes play an essential role in the biosynthesis of unsaturated fatty acids (UFAs). In this study, we identified seven "first desaturase" subfamily genes (Cfor-desatA1, Cfor-desatA2-a, Cfor-desatA2-b, Cfor-desatB-a, Cfor-desatB-b, Cfor-desatD and Cfor-desatE) from the Formosan subterranean termite Coptotermes formosanus. These desaturases were highly expressed in the cuticle and fat body of C. formosanus. Inhibition of either the Cfor-desatA2-a or Cfor-desatA2-b gene resulted in a significant decrease in the contents of fatty acids (C16:0, C18:0, C18:1 and C18:2) in worker castes. Moreover, we observed that inhibition of most of desaturase genes identified in this study had a negative impact on the survival rate and desiccation tolerance of workers. Interestingly, when normal soldiers were reared together with dsCfor-desatA2-b-treated workers, they exhibited higher mortality, suggesting that desaturase had an impact on trophallaxis among C. formosanus castes. Our findings shed light on the novel roles of desaturase family genes in the eusocial termite C. formosanus.
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Affiliation(s)
- Danni Xu
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, College of Advanced Agricultural Sciences, Zhejiang A&F University, Hangzhou, China
| | - Yuxin Tong
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, College of Advanced Agricultural Sciences, Zhejiang A&F University, Hangzhou, China
- School of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou, China
| | - Bosheng Chen
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, College of Advanced Agricultural Sciences, Zhejiang A&F University, Hangzhou, China
| | - Baoling Li
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, College of Advanced Agricultural Sciences, Zhejiang A&F University, Hangzhou, China
| | - Shengyin Wang
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, College of Advanced Agricultural Sciences, Zhejiang A&F University, Hangzhou, China
| | - Dayu Zhang
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, College of Advanced Agricultural Sciences, Zhejiang A&F University, Hangzhou, China
- School of Forestry and Biotechnology, Zhejiang A&F University, Hangzhou, China
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Richardson S, Sun Q. Effects of soil moisture on tunneling, survivorship, and food consumption of the Formosan and eastern subterranean termites (Blattodea: Rhinotermitidae). Environ Entomol 2023; 52:539-545. [PMID: 37300303 DOI: 10.1093/ee/nvad049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2023] [Revised: 04/26/2023] [Accepted: 05/26/2023] [Indexed: 06/12/2023]
Abstract
Soil moisture is a critical environmental factor for the survival and behavior of subterranean termites (family Rhinotermitidae). The invasive Formosan subterranean termite, Coptotermes formosanus Shiraki, and the native eastern subterranean termite, Reticulitermes flavipes (Kollar), co-occur in the southeastern United States, while R. flavipes is distributed in a wider geoclimatic range. Previous studies showed that subterranean termites preferred higher soil moisture levels for tunneling and feeding; however, the impacts of constant moisture remained to be characterized to understand their moisture tolerance. In this study, we hypothesized that different soil moisture regimes can alter termite foraging and survival, and that the effects differ between the two species. The tunneling activity, survivorship, and food consumption of termites were documented for 28 days with different sand moisture conditions ranging from no moisture to full saturation (0%, 1%, 5%, 15%, 25%, and 30%). We found that there were no significant differences in the responses between C. formosanus and R. flavipes. In both species, termites did not survive or tunnel with 0% moisture. Termites performed tunneling with only 1% sand moisture, although they did not survive for 28 days. A minimal of 5% sand moisture was required for survival, and there were no significant differences in survivorship, tunneling activity, or food consumption among moisture contents of 5-30%. The results suggest that subterranean termites are resilient to moisture extremes. Colonies can tolerate low moisture conditions in their foraging environment for extended times, which may allow them to tunnel and find new moisture sources for colony survival.
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Affiliation(s)
- Steven Richardson
- Department of Entomology, Louisiana State University Agricultural Center, 404 Life Sciences Building, Baton Rouge, LA 70803, USA
- Department of Entomology and Nematology, University of Florida, Gainesville, FL 32608, USA
| | - Qian Sun
- Department of Entomology, Louisiana State University Agricultural Center, 404 Life Sciences Building, Baton Rouge, LA 70803, USA
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Chen WW, Zhang H, Chen Y, Zeng WH, Li ZQ. Combined use of lipopolysaccharide-binding protein dsRNA and Gram-negative bacteria for pest management of Coptotermes formosanus. Pest Manag Sci 2023; 79:2299-2310. [PMID: 36775842 DOI: 10.1002/ps.7405] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 02/04/2023] [Accepted: 02/12/2023] [Indexed: 06/02/2023]
Abstract
BACKGROUND RNA interference (RNAi) technology is an environmentally friendly strategy for controlling insect pests. Lipopolysaccharide-binding protein (LBP) recognizes lipopolysaccharides, which are a major outer membrane constituent of Gram-negative bacteria. We propose that the LBP gene is a potential target for termite management; however, to date, no studies have examined this gene in termites. RESULTS In this study, we cloned the LBP gene of Coptotermes formosanus (Cf) and found that the mortality rate of termite workers significantly increased, and the repellence of these workers to Gram-negative bacteria was suppressed after knockdown of CfLBP using double-stranded RNA (dsRNA) injection and feeding. Moreover, the mortality rate of termite workers fed with CfLBP dsRNA and three Gram-negative bacteria (provided separately) was over 50%, which was much higher than that of termites treated with either CfLBP dsRNA or Gram-negative bacteria. Finally, we found that CfLBP impacts the IMD pathway to regulate the immune response of C. formosanus to Gram-negative bacteria. CONCLUSION CfLBP plays a important role in the immune defense of termites against Gram-negative bacteria. It can be used as an immunosuppressant for RNAi-based termite management and is an ideal target for termite control based on the combined use of RNAi and pathogenic bacteria. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Affiliation(s)
- Wei-Wen Chen
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou, China
| | - Hong Zhang
- State Key Laboratory of Biocontrol and School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Yong Chen
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou, China
| | - Wen-Hui Zeng
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou, China
| | - Zhi-Qiang Li
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou, China
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Chen WW, Zeng WH, Shen DN, Feng SY, Li ZQ. Genome-wide identification of Coptotermes formosanus immune genes and their potential roles in termite control. Gene 2023; 877:147569. [PMID: 37330022 DOI: 10.1016/j.gene.2023.147569] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 06/07/2023] [Accepted: 06/12/2023] [Indexed: 06/19/2023]
Abstract
In recent years, the use of microbes to control termites has attracted increasing attention. It was found that pathogenic bacteria, nematodes, and fungi effectively control termites under laboratory conditions. However, their effects have not been replicated in the field, and one reason for this is the complex immune defense mechanisms of termites, which are mainly regulated by immune genes. Therefore, altering the expression of immune genes may have a positive influence on the biocontrol efficacy of termites. Coptotermes formosanus Shiraki is one of the most economically important termite pests worldwide. Currently, the large-scale identification of immune genes in C. formosanus is primarily based on cDNA library or transcriptome data rather than at the genomic level. In this study, we identified the immune genes of C. formosanus according to genome-wide analysis. In addition, our transcriptome analysis showed that immune genes were significantly downregulated when C. formosanus was exposed to the fungus Metarhizium anisopliae or nematodes.. Finally, we found that injecting dsRNA to inhibit three immune genes (CfPGRP-SC1, CfSCRB3, and CfHemocytin), which recognize infectious microbes, significantly increased the lethal effect of M. anisopliae on termites. These immune genes show great potential for C. formosanus management based on RNAi. These results also increase the number of known immune genes in C. formosanus which will provide a more comprehensive insight into the molecular basis of immunity in termites.
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Affiliation(s)
- Wei-Wen Chen
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou, China
| | - Wen-Hui Zeng
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou, China
| | - Dan-Ni Shen
- School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Shu-Yi Feng
- School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Zhi-Qiang Li
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou, China.
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Dar MA, Xie R, Pandit RS, Danso B, Dong C, Sun J. Exploring the region-wise diversity and functions of symbiotic bacteria in the gut system of wood-feeding termite, Coptotermes formosanus, toward the degradation of cellulose, hemicellulose, and organic dyes. Insect Sci 2022; 29:1414-1432. [PMID: 35134272 DOI: 10.1111/1744-7917.13012] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2021] [Revised: 12/28/2021] [Accepted: 01/19/2022] [Indexed: 06/14/2023]
Abstract
The wood-feeding termite Coptotermes formosanus represents a unique and impressive system for lignocellulose degradation. The highly efficient digestion of lignocellulose is achieved through symbiosis with gut symbionts like bacteria. Despite extensive research during the last three decades, diversity of bacterial symbionts residing in individual gut regions of the termite and their associated functions is still lacking. To this end, cellulose, xylan, and dye-decolorization bacteria residing in foregut, midgut, and hindgut regions of C. formosanus were enlisted by using enrichment and culture-dependent molecular methods. A total of 87 bacterial strains were successfully isolated from different gut regions of C. formosanus which belonged to 27 different species of 10 genera, majorly affiliated with Proteobacteria (80%) and Firmicutes (18.3%). Among the gut regions, 37.9% of the total bacterial isolates were observed in the hindgut that demonstrated predominance of cellulolytic bacteria (47.6%). The majority of the xylanolytic and dye-decolorization bacteria (50%) were obtained from the foregut and midgut, respectively. Actinobacteria represented by Dietza sp. was observed in the hindgut only. Based on species richness, the highest diversity was observed in midgut and hindgut regions each of which harbored seven unique bacterial species. The members of Enterobacter, Klebsiella, and Pseudomonas were common among the gut regions. The lignocellulolytic activities of the selected potential bacteria signpost their assistance to the host for lignocellulose digestion. The overall results indicate that C. formosanus harbors diverse communities of lignocellulolytic bacteria in different regions of the gut system. These observations will significantly advance our understanding of the termite-bacteria symbiosis and their microbial ecology uniquely existed in different gut regions of C. formosanus, which may further shed a light on its potential values at termite-modeled biotechnology.
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Affiliation(s)
- Mudasir A Dar
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, Jiangsu Province, China
- Department of Zoology, Savitribai Phule Pune University, Ganeshkhind, Pune, India
| | - Rongrong Xie
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, Jiangsu Province, China
| | | | - Blessing Danso
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, Jiangsu Province, China
| | - Chenchen Dong
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, Jiangsu Province, China
| | - Jianzhong Sun
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, Jiangsu Province, China
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Ngo K, Castillo P, Laine RA, Sun Q. Effects of Menadione on Survival, Feeding, and Tunneling Activity of the Formosan Subterranean Termite. Insects 2021; 12:insects12121109. [PMID: 34940197 PMCID: PMC8707845 DOI: 10.3390/insects12121109] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 11/30/2021] [Accepted: 12/02/2021] [Indexed: 11/16/2022]
Abstract
The Formosan subterranean termite, Coptotermes formosanus Shiraki, is a highly destructive pest and a cosmopolitan invasive species. Sustainable termite management methods have been improving with the search for novel insecticides that are effective, safe, and cost efficient. Menadione, also known as vitamin K3, is a synthetic analogue and biosynthetic precursor of vitamin K with low mammalian toxicity. Menadione has shown insecticidal activity in several insects, presumably due to interference with mitochondrial oxidative phosphorylation. However, little is known about its effectiveness against termites. In this study, we evaluated the toxicity and repellency of menadione in C. formosanus. Our results showed that menadione affected the survival and feeding activity of termites both in filter paper and substrate (sand) treatments, and menadione influenced termite tunneling activity in treated sand. In a no-choice assay, ≥90% mortality after seven days and minimal or no food consumption were recorded when sand was treated with menadione at 6 to 600 ppm. In a two-choice assay with a combination of treated and untreated sand, termites were deterred by menadione at 6 to 600 ppm and exhibited low mortality (≤30%) over seven days, while tunneling activity was prevented with 60 to 600 ppm of menadione treatment. Overall, our study demonstrated dose-dependent toxicity and repellency of menadione in C. formosanus. The potential use of menadione as an alternative termite control agent is discussed.
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Affiliation(s)
- Kieu Ngo
- Department of Entomology, Louisiana State University Agricultural Center, Baton Rouge, LA 70803, USA; (K.N.); (P.C.)
| | - Paula Castillo
- Department of Entomology, Louisiana State University Agricultural Center, Baton Rouge, LA 70803, USA; (K.N.); (P.C.)
| | - Roger A. Laine
- Departments of Biological Sciences and Chemistry, Louisiana State University, Baton Rouge, LA 70803, USA
- Correspondence: (R.A.L.); (Q.S.)
| | - Qian Sun
- Department of Entomology, Louisiana State University Agricultural Center, Baton Rouge, LA 70803, USA; (K.N.); (P.C.)
- Correspondence: (R.A.L.); (Q.S.)
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Wu W, Hou Y, Zhang S, Chen Y, Zeng W, Li Z. GC/TOF-MS-Based Metabolomics Reveals Altered Metabolic Profiles in Wood-Feeding Termite Coptotermes formosanus Shiraki Digesting the Weed Mikania micrantha Kunth. Insects 2021; 12:927. [PMID: 34680696 PMCID: PMC8537488 DOI: 10.3390/insects12100927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Revised: 10/08/2021] [Accepted: 10/08/2021] [Indexed: 11/16/2022]
Abstract
Effective approaches to exploiting the biomass of the abundant invasive weed Mikania micrantha Kunth are limited. Termites have been a focus of significant attention as mediators of biomass-processing owing to their ability to digest lignocellulose. Here, the GC/TOF-MS approach was employed to assess the effects of a diet composed of M. micrantha leaves on Coptotermes formosanus workers, with the growth performance of these workers also being assessed. The workers increased their dietary intake when fed M. micrantha leaves, with a concomitant gradual increase in mortality rate. A total of 62 differentially abundant metabolites and nine significantly affected pathways were found when comparing termites fed M. micrantha leaves to pinewood. Key metabolites, including carbohydrates, polyols, 4-hydroxyphenylacetic acid, and their related metabolic pathways, suggested that termites can digest and utilize M. micrantha-derived lignocellulose. However, changes in the tryptophan metabolism, tyrosine metabolism, and sphingolipid metabolism suggest an adverse effect of M. micrantha leaves on antioxidant activity and signal transduction in termites. Overall, this study identified the key metabolites and pathways associated with the response of these termites to dietary changes and the effect of M. micrantha on termites.
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Affiliation(s)
- Wenjing Wu
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou 510260, China; (W.W.); (S.Z.); (Y.C.); (W.Z.)
| | - Yahui Hou
- Guangzhou Institute of Forestry and Landscape Architecture, Guangzhou 510405, China;
| | - Shijun Zhang
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou 510260, China; (W.W.); (S.Z.); (Y.C.); (W.Z.)
| | - Yong Chen
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou 510260, China; (W.W.); (S.Z.); (Y.C.); (W.Z.)
| | - Wenhui Zeng
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou 510260, China; (W.W.); (S.Z.); (Y.C.); (W.Z.)
| | - Zhiqiang Li
- Guangdong Key Laboratory of Animal Conservation and Resource Utilization, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Institute of Zoology, Guangdong Academy of Sciences, Guangzhou 510260, China; (W.W.); (S.Z.); (Y.C.); (W.Z.)
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9
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Wen C, Xiong H, Wen J, Wen X, Wang C. Trichoderma Species Attract Coptotermes formosanus and Antagonize Termite Pathogen Metarhizium anisopliae. Front Microbiol 2020; 11:653. [PMID: 32328057 PMCID: PMC7160823 DOI: 10.3389/fmicb.2020.00653] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2019] [Accepted: 03/23/2020] [Indexed: 11/25/2022] Open
Abstract
Although subterranean termites live within soil, little attention has been paid on the potential interaction among subterranean termites and soil microbes. Herein, we conducted different choice tests to investigate aggregation and tunneling behaviors of Coptotermes formosanus Shiraki responding to soil/sand treated with conidia of seven soil fungi, Trichoderma longibrachiatum Rifai, Trichoderma koningii Oud., Trichoderma hamatum (Bon.) Bain., Trichoderma atroviride Karsten, Trichoderma spirale Indira and Kamala, Trichoderma harzianum Rifai, and Trichoderma viride Pers. ex Fries. In aggregation-choice test, soil treated with nearly all Trichoderma species tested (except T. koningii) significantly increased termite aggregation compared with untreated soil. In tunneling-choice tests, termites produced significantly larger tunnels in sand treated with T. longibrachiatum or T. koningii than that in untreated sand. We hypothesized that Trichoderma species could benefit termites by protecting them from infection of the entomopathogenic fungus Metarhizium anisopliae (Metschn) Sorokin, and three Trichoderma species that attracted termites (T. longibrachiatum, T. atroviride, and T. harzianum) were tested. The antagonism tests showed that the three Trichoderma species suppressed growth of M. anisopliae. Also, the median lethal time (LT50) of termites exposed to both Trichoderma species and M. anisopliae was significantly longer than termites exposed to M. anisopliae alone. Interestingly, though significantly fewer termites aggregated in soil treated with M. anisopliae conidia compared with untreated soil, M. anisopliae conidia mixed with T. longibrachiatum or T. harzianum were no longer repellent to termites. Our results showed that the fungi in the genus Trichoderma (1) exerted generally attractive effects on termites, (2) protected termites from the infection of entomopathogenic fungus, and (3) altered pathogen-avoiding behaviors of termites. Future studies will be required to understand the mechanisms underlying these newly discovered effects.
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Affiliation(s)
- Chao Wen
- Guangdong Key Laboratory for Innovation Development and Utilization of Forest Plant Germplasm, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China.,Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
| | - Hongpeng Xiong
- Guangdong Key Laboratory for Innovation Development and Utilization of Forest Plant Germplasm, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
| | - Junbao Wen
- Beijing Key Laboratory for Forest Pest Control, College of Forestry, Beijing Forestry University, Beijing, China
| | - Xiujun Wen
- Guangdong Key Laboratory for Innovation Development and Utilization of Forest Plant Germplasm, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
| | - Cai Wang
- Guangdong Key Laboratory for Innovation Development and Utilization of Forest Plant Germplasm, College of Forestry and Landscape Architecture, South China Agricultural University, Guangzhou, China
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Lee S, Su N, Song H, Lee S. Minimizing moving distance in deposition behavior of the subterranean termite. Ecol Evol 2020; 10:2145-2152. [PMID: 32128145 PMCID: PMC7042759 DOI: 10.1002/ece3.6051] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Revised: 12/12/2019] [Accepted: 01/07/2020] [Indexed: 11/06/2022] Open
Abstract
Subterranean termite nests are located underground and termites forage out by constructing tunnels to reach food resources, and tunneling behavior is critical in order to maximize the foraging efficiency. Excavation, transportation, and deposition behavior are involved in the tunneling, and termites have to move back and forth to do this. Although there are three sequential behaviors, excavation has been the focus of most previous studies. In this study, we investigated the deposition behavior of the Formosan subterranean termite, Coptotermes formosanus Shiraki, in experimental arenas having different widths (2, 3, and 4 mm), and characterized the function of deposited particles. We also simulated moving distance of the termites in different functions. Our results showed that total amounts of deposited particles were significantly higher in broad (4 mm width) than narrow (2 mm) tunnels and most deposited particles were observed near the tip of the tunnel regardless of tunnel widths. In addition, we found that deposited particles followed a quadratic decrease function, and simulation results showed that moving distance of termites in this function was the shortest. The quadratic decrease function of deposited particles in both experiment and simulation suggested that short moving distance in the decrease quadratic function is a strategy to minimize moving distance during the deposition behavior.
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Affiliation(s)
- Sang‐Bin Lee
- Department of Entomology and NematologyFt. Lauderdale Research and Education CenterInstitute of Food and Agricultural SciencesUniversity of FloridaFt. LauderdaleFLUSA
| | - Nan‐Yao Su
- Department of Entomology and NematologyFt. Lauderdale Research and Education CenterInstitute of Food and Agricultural SciencesUniversity of FloridaFt. LauderdaleFLUSA
| | - Hark‐Soo Song
- Division of Industrial MathematicsNational Institute for Mathematical SciencesDaejeonKorea
| | - Sang‐Hee Lee
- Division of Industrial MathematicsNational Institute for Mathematical SciencesDaejeonKorea
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Zhou Y, Li X, Yan D, Addai Peprah F, Ji X, Fletcher EE, Wang Y, Wang Y, Gu J, Lin F, Shi H. Multifunctional elastin-like polypeptide renders β-glucosidase enzyme phase transition and high stability. Biotechnol Biofuels 2019; 12:157. [PMID: 31249620 PMCID: PMC6589881 DOI: 10.1186/s13068-019-1497-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2019] [Accepted: 06/11/2019] [Indexed: 05/10/2023]
Abstract
BACKGROUND In the enzymatic conversion of biomass, it becomes an important issue to efficiently and cost-effectively degrade cellulose into fermentable glucose. β-Glucosidase (Bgluc), an essential member of cellulases, plays a critical role in cellulosic biomass degradation. The difficulty in improving the stability of Bgluc has been a bottleneck in the enzyme-dependent cellulose degradation. The traditional method of protein purification, however, leads to higher production cost and a decrease in activity. To simplify and efficiently purify Bgluc with modified special properties, Bgluc-tagged ELP and His with defined phase transitions was designed to facilitate the process. RESULTS Here, a novel binary ELP and His tag was fused with Bgluc from termite Coptotermes formosanus to construct a Bgluc-linker-ELP-His recombinant fusion protein (BglucLEH). The recombinant plasmid Bgluc expressing a His tag (BglucH) was also constructed. The BglucLEH and BglucH were expressed in E. coli BL21 and purified using inverse transition cycling (ITC) or Ni-NTA resin. The optimum salt concentration for the ITC purification of BglucLEH was 0.5 M (NH4)2SO4 and the specific activity of BglucLEH purified by ITC was 75.5 U/mg for substrate p-NPG, which was slightly higher than that of BglucLEH purified by Ni-NTA (68.2 U/mg). The recovery rate and purification fold of BglucLEH purified by ITC and Ni-NTA were 77.8%, 79.1% and 12.60, 11.60, respectively. The results indicated that purification with ITC was superior to the traditional Ni-NTA. The K m of BglucLEH and BglucH for p-NPG was 5.27 and 5.73 mM, respectively. The K ca t/K m (14.79 S-1 mM-1) of BglucLEH was higher than that of BglucH (12.10 S-1 mM-1). The effects of ELP tag on the enzyme activity, secondary structure and protein stability were also studied. The results showed that ELP tag did not affect the secondary structure or enzyme activity of Bgluc. More importantly, ELP improved the protein stability in harsh conditions such as heating and exposure to denaturant. CONCLUSION The Bgluc-linker-ELP-His system shows wide application prospect in maintaining the activity, efficient purification and improving the stability of Bgluc. These properties of BglucLEH make it an interesting tool to reduce cost, to improve the efficiency of biocatalyst and potentially to enhance the degradation of lignocellulosic biomass.
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Affiliation(s)
- Yang Zhou
- Institute of Life Sciences, Jiangsu University, No. 301 Xuefu Road, Zhenjiang, 212013 People’s Republic of China
| | - Xiaofeng Li
- Institute of Life Sciences, Jiangsu University, No. 301 Xuefu Road, Zhenjiang, 212013 People’s Republic of China
| | - Dandan Yan
- Institute of Life Sciences, Jiangsu University, No. 301 Xuefu Road, Zhenjiang, 212013 People’s Republic of China
| | - Frank Addai Peprah
- Institute of Life Sciences, Jiangsu University, No. 301 Xuefu Road, Zhenjiang, 212013 People’s Republic of China
| | - Xingqi Ji
- Institute of Life Sciences, Jiangsu University, No. 301 Xuefu Road, Zhenjiang, 212013 People’s Republic of China
| | - Emmanuella Esi Fletcher
- Institute of Life Sciences, Jiangsu University, No. 301 Xuefu Road, Zhenjiang, 212013 People’s Republic of China
| | - Yanwei Wang
- Institute of Life Sciences, Jiangsu University, No. 301 Xuefu Road, Zhenjiang, 212013 People’s Republic of China
| | - Yingying Wang
- Institute of Life Sciences, Jiangsu University, No. 301 Xuefu Road, Zhenjiang, 212013 People’s Republic of China
| | - Jie Gu
- Institute of Life Sciences, Jiangsu University, No. 301 Xuefu Road, Zhenjiang, 212013 People’s Republic of China
| | - Feng Lin
- Key Laboratory of Healthy Freshwater Aquaculture, Ministry of Agriculture, Zhejiang Institute of Freshwater Fisheries, Huzhou, 313001 People’s Republic of China
| | - Haifeng Shi
- Institute of Life Sciences, Jiangsu University, No. 301 Xuefu Road, Zhenjiang, 212013 People’s Republic of China
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Geng A, Wu J, Xie RR, Li X, Chang FX, Sun JZ. Characterization of a laccase from a wood-feeding termite, Coptotermes formosanus. Insect Sci 2018; 25:251-258. [PMID: 27800659 DOI: 10.1111/1744-7917.12415] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Revised: 09/27/2016] [Accepted: 10/02/2016] [Indexed: 06/06/2023]
Abstract
Coptotermes formosanus Shiraki is a wood-feeding termite which secretes a series of lignolytic and cellulolytic enzymes for woody biomass degradation. However, the lignin modification mechanism in the termite is largely elusive, and the characteristics of most lignolytic enzymes in termites remain unknown. In this study, a laccase gene lac1 from C. formosanus was heterogeneously expressed in insect Sf9 cells. The purified Lac1 showed strong activities toward hydroquinone (305 mU/mg) and 2,6-dimethoxyphenol (2.9 mU/mg) with low Km values, but not veratryl alcohol or 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid). Lac1 could function well from pH 4.5 to 7.5, and its activity was significantly inhibited by H2 O2 at above 4.85 mmol/L (P < 0.01). In addition, the lac1 gene was found to be mainly expressed in the salivary glands and foregut of C. formosanus, and seldom in the midgut or hindgut. These findings suggested that Lac1 is a phenol-oxidizing laccase like RflacA and RflacB from termite Reticulitermes flavipes, except that Lac1 was found to be more efficient in phenol oxidation, and it did not require H2 O2 for its function. It is suspected that this kind of termite laccase might only be able to directly oxidize low redox-potential substrates, and the high redox-potential groups in lignin might be oxidized by other enzymes in the termite or by using the Fenton reaction.
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Affiliation(s)
- Alei Geng
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, Jiangsu, China
| | - Jian Wu
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, Jiangsu, China
| | - Rong-Rong Xie
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, Jiangsu, China
| | - Xia Li
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, Jiangsu, China
| | - Fu-Xiang Chang
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, Jiangsu, China
| | - Jian-Zhong Sun
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, Jiangsu, China
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Geng A, Cheng Y, Wang Y, Zhu D, Le Y, Wu J, Xie R, Yuan JS, Sun J. Transcriptome analysis of the digestive system of a wood-feeding termite ( Coptotermes formosanus) revealed a unique mechanism for effective biomass degradation. Biotechnol Biofuels 2018; 11:24. [PMID: 29434667 PMCID: PMC5797411 DOI: 10.1186/s13068-018-1015-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 01/10/2018] [Indexed: 05/03/2023]
Abstract
BACKGROUND Wood-feeding termite, Coptotermes formosanus Shiraki, represents a highly efficient system for biomass deconstruction and utilization. However, the detailed mechanisms of lignin modification and carbohydrate degradation in this system are still largely elusive. RESULTS In order to reveal the inherent mechanisms for efficient biomass degradation, four different organs (salivary glands, foregut, midgut, and hindgut) within a complete digestive system of a lower termite, C. formosanus, were dissected and collected. Comparative transcriptomics was carried out to analyze these organs using high-throughput RNA sequencing. A total of 71,117 unigenes were successfully assembled, and the comparative transcriptome analyses revealed significant differential distributions of GH (glycosyl hydrolase) genes and auxiliary redox enzyme genes in different digestive organs. Among the GH genes in the salivary glands, the most abundant were GH9, GH22, and GH1 genes. The corresponding enzymes may have secreted into the foregut and midgut to initiate the hydrolysis of biomass and to achieve a lignin-carbohydrate co-deconstruction system. As the most diverse GH families, GH7 and GH5 were primarily identified from the symbiotic protists in the hindgut. These enzymes could play a synergistic role with the endogenous enzymes from the host termite for biomass degradation. Moreover, twelve out of fourteen genes coding auxiliary redox enzymes from the host termite origin were induced by the feeding of lignin-rich diets. This indicated that these genes may be involved in lignin component deconstruction with its redox network during biomass pretreatment. CONCLUSION These findings demonstrate that the termite digestive system synergized the hydrolysis and redox reactions in a programmatic process, through different parts of its gut system, to achieve a maximized utilization of carbohydrates. The detailed unique mechanisms identified from the termite digestive system may provide new insights for advanced design of future biorefinery.
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Affiliation(s)
- Alei Geng
- Biofuels Institute of Jiangsu University, School of Environmental and Safety Engineering, Jiangsu University, Zhenjiang, 212013 Jiangsu China
| | - Yanbing Cheng
- Synthetic and Systems Biology Innovation Hub, Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX 77843 USA
| | - Yongli Wang
- Biofuels Institute of Jiangsu University, School of Environmental and Safety Engineering, Jiangsu University, Zhenjiang, 212013 Jiangsu China
| | - Daochen Zhu
- Biofuels Institute of Jiangsu University, School of Environmental and Safety Engineering, Jiangsu University, Zhenjiang, 212013 Jiangsu China
| | - Yilin Le
- Biofuels Institute of Jiangsu University, School of Environmental and Safety Engineering, Jiangsu University, Zhenjiang, 212013 Jiangsu China
| | - Jian Wu
- Biofuels Institute of Jiangsu University, School of Environmental and Safety Engineering, Jiangsu University, Zhenjiang, 212013 Jiangsu China
| | - Rongrong Xie
- Biofuels Institute of Jiangsu University, School of Environmental and Safety Engineering, Jiangsu University, Zhenjiang, 212013 Jiangsu China
| | - Joshua S. Yuan
- Biofuels Institute of Jiangsu University, School of Environmental and Safety Engineering, Jiangsu University, Zhenjiang, 212013 Jiangsu China
- Synthetic and Systems Biology Innovation Hub, Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX 77843 USA
| | - Jianzhong Sun
- Biofuels Institute of Jiangsu University, School of Environmental and Safety Engineering, Jiangsu University, Zhenjiang, 212013 Jiangsu China
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Kakkar G, Su NY. Molting drives mortality in foraging populations of Formosan subterranean termites (Isoptera: Rhinotermitidae) baited with a chitin synthesis inhibitor, noviflumuron. Pest Manag Sci 2018; 74:219-224. [PMID: 28800201 DOI: 10.1002/ps.4699] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2017] [Revised: 08/04/2017] [Accepted: 08/04/2017] [Indexed: 06/07/2023]
Abstract
BACKGROUND The lethal time of a chitin synthesis inhibitor (CSI)-baited colony of Coptotermes formosanus Shiraki largely depends on the time taken for workers to molt after consuming a lethal dose. Given that termite molting biology can regulate the time to elimination of a baited termite colony, the objective of this study was to determine how the fasting period (an important element of the worker molting cycle) and acquisition of the lethal dose can impact the total elimination period for a colony. RESULTS Noviflumuron eliminated the foraging population over a 30 m-long foraging arena within 9 weeks. However, mortality in treatment groups did not begin until day 11. The 10-day lag post treatment corresponds to the fasting period during which workers to prepare for ecdysis on the 11th day, at which time mortality occurs due to the effect of CSI. CONCLUSION This study shows that, with the exception of successful molting events during the first 10 days after baiting, mortality among workers is inevitable in the next molt with lethal doses of noviflumuron. The 10-day fasting period can comprise at least 22% of a molt cycle (45 days for a fourth worker instar or lower), and can provide a window during which a worker escapes the effect of CSI bait, thereby extending the total time needed for elimination of a colony. © 2017 Society of Chemical Industry.
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Affiliation(s)
- Garima Kakkar
- University of Florida/Institute of Food and Agricultural Science, Ft. Pierce, FL, USA
| | - Nan-Yao Su
- University of Florida/Institute of Food and Agricultural Science, Department of Entomology and Nematology, Fort Lauderdale Research and Education Center, Davie, FL, USA
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15
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Su NY, Osbrink W, Kakkar G, Mullins A, Chouvenc T. Foraging Distance and Population Size of Juvenile Colonies of the Formosan Subterranean Termite (Isoptera: Rhinotermitidae) in Laboratory Extended Arenas. J Econ Entomol 2017; 110:1728-1735. [PMID: 28605564 DOI: 10.1093/jee/tox153] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2017] [Indexed: 06/07/2023]
Abstract
The relationship between colony size and foraging distance was examined in extended foraging arenas with juvenile colonies of the Formosan subterranean termite, Coptotermes formosanus Shiraki. Our results showed that as long as royal pairs are present, larger colonies foraged at longer distances, and the oldest workers distributed farther away from the central nest. The results agree with the scaling model that predicts a large foraging range for animals of larger body size. An analysis of published data from population survey studies and field trials of bait toxicants showed that field colonies of the eastern subterranean termite, Reticulitermes flavipes (Kollar), follow the scaling model, while C. formosanus colonies were inconsistent with the model prediction. Reasons for the inconsistency with field data of C. formosanus are discussed.
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Affiliation(s)
- Nan-Yao Su
- Department of Entomology and Nematology, Ft. Lauderdale Research and Education Center, University of Florida, Ft. Lauderdale, FL
| | - Weste Osbrink
- Knipling-Bushland U.S. Livestock Insects Research Laboratory, USDA-ARS-SPA, Kerrville, TX
| | - Garima Kakkar
- University of Florida, Institute of Food and Agricultural Science Multi-County Extension, Ft. Pierce, FL
| | - Aaron Mullins
- Department of Entomology and Nematology, Ft. Lauderdale Research and Education Center, University of Florida, Ft. Lauderdale, FL
| | - Thomas Chouvenc
- Department of Entomology and Nematology, Ft. Lauderdale Research and Education Center, University of Florida, Ft. Lauderdale, FL
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Tong RL, Grace JK, Mason M, Krushelnycky PD, Spafford H, Aihara-Sasaki M. Termite Species Distribution and Flight Periods on Oahu, Hawaii. Insects 2017; 8:E58. [PMID: 28587241 DOI: 10.3390/insects8020058] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Revised: 05/27/2017] [Accepted: 06/01/2017] [Indexed: 11/17/2022]
Abstract
Termites are economically-important structural pests, costing residents of Hawaii over $100 million annually. On Oahu, the last published termite swarming survey occurred from 1969 to 1971, and the last termite hand-collection survey occurred from 1998 to 2000. To contribute data on termite occurrences on Oahu, a light-trap survey took place from February 2011 to September 2012, and a hand-collection survey occurred from September to November 2012. Formosan subterranean termite, Coptotermes formosanus Shiraki, swarming was compared over the duration of the study, finding peak swarming in May 2011. C. formosanus alate activity density was regressed with environmental factors, finding a negative correlation with average wind speed and a positive correlation with average rainfall. Coptotermes gestroi (Wasmann) alates were observed in April, June, and July 2011 and in June 2012. Four species of termites were found in the hand-collection survey of 44 sites: Incisitermes immigrans (Snyder) (n = 8/44), C. formosanus (n = 2/44), Cryptotermes cynocephalus Light (n = 1/44), and Neotermes sp. (n = 1/44). This study contributes to distribution data for termite species on Oahu and records alate activity for two important termite pests.
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Liu XJ, Xie L, Liu N, Zhan S, Zhou XG, Wang Q. RNA interference unveils the importance of Pseudotrichonympha grassii cellobiohydrolase, a protozoan exoglucanase, in termite cellulose degradation. Insect Mol Biol 2017; 26:233-242. [PMID: 27991709 DOI: 10.1111/imb.12287] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Based on prior work, a cellulase from glycosyl hydrolase family 7 (GHF7) was identified and found to be expressed at a high level in Coptotermes formosanus. To determine the function of GHF7 family members in vivo, we used RNA interference (RNAi) to functionally analyse the exoglucanase gene Pseudotrichonympha grassii cellobiohydrolase gene (PgCBH), which was highly expressed in Pseudotrichonympha grassii, a flagellate found in the hindgut of C. formosanus. In this study, the expression level of PgCBH was down-regulated by RNAi, causing the death of P. grassii, but no effect was observed for other flagellates found in C. formosanus. RNAi also resulted in significantly reduced exoglucanase activity, and no effect was observed for endoglucanase and β-glucosidase activities. This result demonstrated that the PgCBH gene plays a role in the protist lignocellulolytic process and is also important for host survival. PgCBH can be used as a target gene and has potential as a bioinsecticide for use against termites.
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Affiliation(s)
- X-J Liu
- Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Shanghai, China
| | - L Xie
- Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Shanghai, China
| | - N Liu
- Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
- University of Chinese Academy of Sciences, Shanghai, China
| | - S Zhan
- Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
| | - X-G Zhou
- Department of Entomology, University of Kentucky, KY, USA
| | - Q Wang
- Key Laboratory of Insect Developmental and Evolutionary Biology, Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China
- Institut Pasteur of Shanghai, Chinese Academy of Sciences, Shanghai, China
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Ismayati M, Nakagawa-Izumi A, Kamaluddin NN, Ohi H. Toxicity and Feeding Deterrent Effect of 2-Methylanthraquinone from the Wood Extractives of Tectona grandis on the Subterranean Termites Coptotermes formosanus and Reticulitermes speratus. Insects 2016; 7:insects7040063. [PMID: 27834795 PMCID: PMC5198211 DOI: 10.3390/insects7040063] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/20/2016] [Revised: 11/02/2016] [Accepted: 11/03/2016] [Indexed: 11/16/2022]
Abstract
No-choice feeding tests using ethanol, chloroform, and acetone extractives of teak (Tectona grandis) heartwood clearly showed feeding deterrent activity and toxicity to the subterranean termite Reticulitermes speratus. The amount of 2-methylanthraquinone (MAQ) in teak wood extractives was not related to the feeding deterrents or toxicity, as shown by the no-choice feeding tests conducted using crude extractives containing various amounts of MAQ, MAQ alone, and fractions of crude extractives. As a native pest, the subterranean termite Coptotermes formosanus was more tolerant to the fractions of crude extractives than Reticulitermes speratus, and the mortality observed in C. formosanus was not due to the presence of MAQ.
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Affiliation(s)
- Maya Ismayati
- Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba 305-0872, Japan.
- Research Center for Biomaterial, Indonesian Institute of Sciences (LIPI), Jl. Raya Bogor km. 46 Cibinong, Bogor 16911, Indonesia.
| | - Akiko Nakagawa-Izumi
- Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba 305-0872, Japan.
| | | | - Hiroshi Ohi
- Graduate School of Life and Environmental Sciences, University of Tsukuba, Tsukuba 305-0872, Japan.
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Wu W, Li Z, Zhang S, Ke Y, Hou Y. Transcriptome response to elevated atmospheric CO 2 concentration in the Formosan subterranean termite, Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae). PeerJ 2016; 4:e2527. [PMID: 27761326 PMCID: PMC5068368 DOI: 10.7717/peerj.2527] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2016] [Accepted: 09/04/2016] [Indexed: 11/27/2022] Open
Abstract
Background Carbon dioxide (CO2) is a pervasive chemical stimulus that plays a critical role in insect life, eliciting behavioral and physiological responses across different species. High CO2 concentration is a major feature of termite nests, which may be used as a cue for locating their nests. Termites also survive under an elevated CO2 concentration. However, the mechanism by which elevated CO2 concentration influences gene expression in termites is poorly understood. Methods To gain a better understanding of the molecular basis involved in the adaptation to CO2 concentration, a transcriptome of Coptotermes formosanus Shiraki was constructed to assemble the reference genes, followed by comparative transcriptomic analyses across different CO2 concentration (0.04%, 0.4%, 4% and 40%) treatments. Results (1) Based on a high throughput sequencing platform, we obtained approximately 20 GB of clean data and revealed 189,421 unigenes, with a mean length and an N50 length of 629 bp and 974 bp, respectively. (2) The transcriptomic response of C. formosanus to elevated CO2 levels presented discontinuous changes. Comparative analysis of the transcriptomes revealed 2,936 genes regulated among 0.04%, 0.4%, 4% and 40% CO2 concentration treatments, 909 genes derived from termites and 2,027 from gut symbionts. Genes derived from termites appears selectively activated under 4% CO2 level. In 40% CO2 level, most of the down-regulated genes were derived from symbionts. (3) Through similarity searches to data from other species, a number of protein sequences putatively involved in chemosensory reception were identified and characterized in C. formosanus, including odorant receptors, gustatory receptors, ionotropic receptors, odorant binding proteins, and chemosensory proteins. Discussion We found that most genes associated with carbohydrate metabolism, energy metabolism, and genetic information processing were regulated under different CO2 concentrations. Results suggested that termites adapt to ∼4% CO2 level and their gut symbionts may be killed under high CO2 level. We anticipate that our findings provide insights into the transcriptome dynamics of CO2 responses in termites and form the basis to gain a better understanding of regulatory networks.
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Affiliation(s)
- Wenjing Wu
- Guangdong Key Laboratory of Integrated Pest Management in Agriculture, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Guangdong Institute of Applied Biological Resources , Guangzhou , Guangdong , China
| | - Zhiqiang Li
- Guangdong Key Laboratory of Integrated Pest Management in Agriculture, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Guangdong Institute of Applied Biological Resources , Guangzhou , Guangdong , China
| | - Shijun Zhang
- Guangdong Key Laboratory of Integrated Pest Management in Agriculture, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Guangdong Institute of Applied Biological Resources , Guangzhou , Guangdong , China
| | - Yunling Ke
- Guangdong Key Laboratory of Integrated Pest Management in Agriculture, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Guangdong Institute of Applied Biological Resources , Guangzhou , Guangdong , China
| | - Yahui Hou
- Guangdong Key Laboratory of Integrated Pest Management in Agriculture, Guangdong Public Laboratory of Wild Animal Conservation and Utilization, Guangdong Institute of Applied Biological Resources, Guangzhou, Guangdong, China; College of Forestry, Northeast Forestry University, Harbin, Heilongjiang, China
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Henderson G, Gautam BK, Wang C. Impact of Ground-Applied Termiticides on the Above-Ground Foraging Behavior of the Formosan Subterranean Termite. Insects 2016; 7:insects7030043. [PMID: 27571108 PMCID: PMC5039556 DOI: 10.3390/insects7030043] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Revised: 08/22/2016] [Accepted: 08/22/2016] [Indexed: 11/16/2022]
Abstract
We conducted a laboratory study to determine the impact of ground-applied termiticides on the above-ground foraging behavior of Coptotermes formosanus. Two concentrations (1 and 10 ppm) each of three termiticides, viz. fipronil, imidacloprid and chlorantraniliprole, were tested. After one month post-treatment (fipronil 10 ppm was run for 12 days only and all other treatments were run for one month), fipronil had the lowest percentage of survival (3%–4%) at both concentrations. Termite survival ranged from 31% to 40% in the case of imidacloprid treatments and 10 ppm chlorantraniliprole. However, 1 ppm chlorantraniliprole did not cause significant mortality compared to the controls. Foraging on the bottom substrate was evident in all replicates for all chemicals initially. However, a portion of the foraging population avoided the ground treatment toxicants after several days of bottom foraging. Only the slower-acting non-repellents created this repellent barrier, causing avoidance behavior that was most likely due to dead termites and fungus buildup on the treated bottom substrate. Fipronil appeared more toxic and faster acting at the concentrations tested, thus limiting this repellent effect. Suggestions by the pest control industry in Louisiana that some non-repellents can create a repellent barrier stranding live termites above ground are supported by this laboratory study.
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Affiliation(s)
- Gregg Henderson
- Department of Entomology, Louisiana State University Agricultural Center, 404 Life Sciences Building, Baton Rouge, LA 70803, USA.
| | - Bal K Gautam
- Department of Entomology, Louisiana State University Agricultural Center, 404 Life Sciences Building, Baton Rouge, LA 70803, USA.
| | - Cai Wang
- Department of Entomology, Louisiana State University Agricultural Center, 404 Life Sciences Building, Baton Rouge, LA 70803, USA.
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Bhatta D, Henderson G, Gautam BK. Toxicity and Nonrepellency of Spinosad and Spinetoram on Formosan Subterranean Termites (Isoptera: Rhinotermitidae). J Econ Entomol 2016; 109:1341-1349. [PMID: 27106223 DOI: 10.1093/jee/tow079] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Accepted: 03/22/2016] [Indexed: 06/05/2023]
Abstract
Spinosyn products, spinosad and spinetoram, are widely used to control various agricultural pests. Spinosad has been tested on Kalotermitidae and Termitidae but not on Rhinotermitidae, the most destructive of termite families. In this study, we tested the effect of spinosad and spinetoram on Coptotermes formosanus Shiraki. Both no-choice and choice tests were conducted using three concentrations, 1 ppm, 25 ppm, and 50 ppm, of the spinosyn products Entrust, Tracer, and Radiant on three substrates, sand, soil, and filter paper. In the no-choice test in sand, >85% mortality was observed at 25 and 50 ppm after 1 d of exposure followed by 100% mortality at 7 d. Similarly, after 7 d at 25 and 50 ppm in soil and filter paper, 100% mortality was observed, but compared to sand at 1 d, mortality was low. In the two-choice test, observations before the onset of termite mortality showed that none of the products or concentrations was repellent. Likewise, in the multiple-choice test, there was no repellency or preference of termites among 1 ppm, 25 ppm, 50 ppm, control, and release chamber at all three concentrations, and the tunnel area in the control and treated choices were not significantly different. These findings support the nonrepellent attribute of spinosyns on C. formosanus .
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Yanagawa A, Imai T, Akino T, Toh Y, Yoshimura T. Olfactory Cues from Pathogenic Fungus Affect the Direction of Motion of Termites, Coptotermes formosanus. J Chem Ecol 2015; 41:1118-26. [PMID: 26563202 PMCID: PMC4675792 DOI: 10.1007/s10886-015-0649-8] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Revised: 07/26/2015] [Accepted: 10/26/2015] [Indexed: 12/04/2022]
Abstract
Formosan subterranean termites, Coptotermes formosanus, tend to avoid pathogen odors when tested in Y-tube olfactometers, but approach and groom exposed nestmates to remove pathogens from their cuticle and maintain a healthy population. To better understand their differential reaction to pathogens and their odors, the relationship between odor cues and direction of motion was examined with the fungus Isaria fumosorosea K3 strain. The results indicate that nestmate odor was strongly attractive only in tests where fungal odors were present in both branches of the olfactometer. Termites generally avoid fungal odors when offered a choice without fungal odor. We also tested termite aversion to 3-octanone and 1-octen-3-ol, major surface chemical compounds of I. fumosorosea K3, and estimated the total mass of these compounds present on the conidial surface by direct extraction method. The total quantity of these chemicals on the surface of fungal conidia was estimated to be approximately 0.01 ng per 107 conidia. This study demonstrates a context dependent behavioral change in termites in response to the odors of pathogenic fungi.
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Affiliation(s)
- Aya Yanagawa
- Research Institute for Sustainable Humanosphere, Kyoto University, Uji, 611-0011, Japan.
| | - Tomoya Imai
- Research Institute for Sustainable Humanosphere, Kyoto University, Uji, 611-0011, Japan
| | - Toshiharu Akino
- Laboratory of Applied Entomology, Kyoto Institute of Technology, Ukyo-ku, Kyoto, 616-8354, Japan
| | - Yoshihiro Toh
- Department of Biology, Faculty of Science, Kyushu University, Higashi-ku, Fukuoka, 812-8581, Japan
| | - Tsuyoshi Yoshimura
- Research Institute for Sustainable Humanosphere, Kyoto University, Uji, 611-0011, Japan
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Ruan G, Song X, Hu Y, Han N, Zhang D. Foraging Activities of Coptotermes formosanus in Subtropical Areas in China. J Econ Entomol 2015; 108:701-706. [PMID: 26470181 DOI: 10.1093/jee/tou030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Accepted: 10/26/2014] [Indexed: 06/05/2023]
Abstract
The foraging activities, including foraging range and seasonal fluctuation of the Formosan subterranean termite, Coptotermes formosanus Shiraki, were investigated in subtropical areas in China. Six mature C. formosanus colonies were selected for this study. Foraging distance and area were conducted in Anqing1, Hengyang, and Wuxi1 colonies, while the seasonal fluctuation was conducted in Wuxi2, Wuwei, and Anqing2 colonies. Mark-release-recapture method analysis showed that the Formosan termites foraged at least 11.5, 28.7, and 56.8 m away from the main nest and covered 98.1, 543.7, and 671.9 m2 of foraging area at Anqing1, Hengyang, and Wuxi1 site, respectively. The seasonal fluctuation in termite colony activity showed an "M shape" pattern according to the wood damages caused by termites at monitoring stations. Peak colony activity at Wuxi2, Wuwei, and Anqing2 occurred in July and October, June and September, July and October, respectively. This study provides critical information for the integrated management of C. formosanus, including baiting application in the subtropical regions of China, where it constitutes the most destructive pest for household structures.
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Affiliation(s)
- Guanhua Ruan
- National Termite Control Center of China, 695 Moganshan Rd., Hangzhou, Zhejiang 310011, China
| | - Xiaogang Song
- National Termite Control Center of China, 695 Moganshan Rd., Hangzhou, Zhejiang 310011, China
| | - Yin Hu
- National Termite Control Center of China, 695 Moganshan Rd., Hangzhou, Zhejiang 310011, China
| | - Na Han
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, College of Agricultural and Food Science, Zhejiang A&F University, 88 Huanchengbei Rd., Linan, Hangzhou, Zhejiang 311300, China
| | - Dayu Zhang
- The Key Laboratory for Quality Improvement of Agricultural Products of Zhejiang Province, College of Agricultural and Food Science, Zhejiang A&F University, 88 Huanchengbei Rd., Linan, Hangzhou, Zhejiang 311300, China. Corresponding author, e-mail:
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Wang C, Henderson G. Clay preference and particle transport behavior of Formosan subterranean termites (Isoptera: Rhinotermitidae): a laboratory study. Insect Sci 2014; 21:785-795. [PMID: 24532284 DOI: 10.1111/1744-7917.12082] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 11/04/2013] [Indexed: 06/03/2023]
Abstract
Although preference and utilization of clay have been studied in many higher termites, little attention has been paid to lower termites, especially subterranean termites. The Formosan subterranean termite, Coptotermes formosanus Shiraki, can modify its habitat by using clay to fill tree cavities. Here, the biological significance of clay on C. formosanus was investigated. Choice tests showed that significantly more termites aggregated in chambers where clay blocks were provided, regardless of colony group, observation period, or nutritional condition (fed or starved). No-choice tests showed that clay had no observable effect on survivorship, live or dry biomass, water content, and tunneling activity after 33-35 d. However, clay appeared to significantly decrease filter paper consumption (dry weight loss). Active particle (sand, paper, and clay) transport behavior was observed in both choice and no-choice tests. When present, clay was preferentially spread on the substrate, attached to the smooth surfaces of the containers, and used to line sand tunnels. Mechanisms and potential application of clay attraction are discussed.
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Affiliation(s)
- Cai Wang
- Department of Entomology, Louisiana State University Agricultural Center, Baton Rouge, LA, 70803, USA
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Veillon L, Bourgeois J, Leblanc A, Henderson G, Marx BD, Muniruzzaman S, Laine RA. myo-Inositol and Phytate Are Toxic to Formosan Subterranean Termites (Isoptera: Rhinotermitidae). J Econ Entomol 2014; 107:1800-1812. [PMID: 26309270 DOI: 10.1603/ec13323] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Several rare and common monosaccharides were screened for toxic effects on the Formosan subterranean termite, Coptotermes formosanus Shiraki, with the aim of identifying environmentally friendly termiticides. myo-Inositol and phytic acid, which are nontoxic to mammals, were identified as potential termite control compounds. Feeding bioassays with termite workers, where both compounds were supplied on filter paper in concentrations from 160.2 to 1,281.7 μg/mm(3), showed concentration-dependent toxicity within 2 wk. Interestingly myo-inositol was nontoxic when administered to termites in agar (40 mg/ml) in the absence of a cellulosic food source, an unexplained phenomenon. In addition, decreased populations of termite hindgut protozoa were observed upon feeding on myo-inositol but not phytate-spiked filter paper. Radiotracer feeding studies using myo-inositol-[2-(3)H] with worker termites showed no metabolism after ingestion over a 2-d feeding period, ruling out metabolites responsible for the selective toxicity.
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Affiliation(s)
- Lucas Veillon
- Department of Biological Sciences, Division of Biochemistry and Molecular Biology, Louisiana State University and A&M College, Baton Rouge, LA 70803
| | - Jared Bourgeois
- Department of Biological Sciences, Division of Biochemistry and Molecular Biology, Louisiana State University and A&M College, Baton Rouge, LA 70803
| | - Amanda Leblanc
- Department of Biological Sciences, Division of Biochemistry and Molecular Biology, Louisiana State University and A&M College, Baton Rouge, LA 70803
| | - Gregg Henderson
- Department of Entomology, Louisiana State University Agricultural Center, Baton Rouge, LA 70803
| | - Brian D Marx
- Department of Experimental Statistics, Louisiana State University and A&M College, Baton Rouge, LA 70803
| | | | - Roger A Laine
- Department of Biological Sciences, Division of Biochemistry and Molecular Biology, Louisiana State University and A&M College, Baton Rouge, LA 70803. Department of Chemistry, Louisiana State University and A&M College, Baton Rouge, LA 70803.
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Cheng SS, Lin CY, Chen YJ, Chung MJ, Chang ST. Insecticidal activities of Cunninghamia konishii Hayata against Formosan subterranean termite, Coptotermes formosanus (Isoptera: Rhinotermitidae). Pest Manag Sci 2014; 70:1215-9. [PMID: 24166745 DOI: 10.1002/ps.3673] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2013] [Revised: 06/28/2013] [Accepted: 10/24/2013] [Indexed: 05/26/2023]
Abstract
BACKGROUND Formosan subterranean termite, Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae), is a major urban pests in many countries throughout the world. In an attempt to find natural products that could be employed in the effective and environmentally friendly control of the termite, this study investigates, for the first time, the insecticidal activities of the wood and leaf essential oils and ethanolic extracts from Cunninghamia konishii Hayata against C. formosanus according to direct contact application. RESULTS Wood and leaf essential oils and wood ethanolic extract showed the excellent antitermitic activities. Among the four fractions of wood ethanolic extract, the hexane-soluble fraction showed the strongest antitermitic activities. In addition, β-elemol and α-cadinol showed excellent inhibitory action against C. formosanus. CONCLUSION The results clearly reveal that the wood and leaf essential oils and ethanolic extract from C. konishii, and their effective constituents, served as potential, eco-friendly termite-control agents.
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Affiliation(s)
- Sen-Sung Cheng
- Experimental Forest, National Taiwan University, Nan-Tou, Taiwan
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Mason M, Aihara-Sasaki M, Grace JK. Teacher Characteristics and Perceptions of Pest Management Curricula: Clues to Adoption and Continuation. Insects 2013; 4:177-84. [PMID: 26464383 DOI: 10.3390/insects4020177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/25/2013] [Revised: 03/20/2013] [Accepted: 04/02/2013] [Indexed: 12/05/2022]
Abstract
Educate to Eradicate is a K-12 curriculum project using termite biology and control as the basis for science education that has been implemented in over 350 Hawaii public school classrooms. To encourage sustained implementation of the project, we aimed to identify factors that influence the adoption and continuation of pest management curricula in public school classrooms. Regression analysis of teacher survey data were used to create predictive models of teacher continuation. Teachers motivated by “exciting students about science”, who perceived increases in “student understanding and comprehension of major termite knowledge concepts” and/or students as “more interested in termites after participating in this project” were more likely to continue curriculum. Teachers who had worked at their current school over 21 years at the time of curriculum adoption, and/or who identified having subject specialties not listed on the survey were less likely to continue curriculum. Additionally, teachers servicing lower socioeconomic level students were less likely to continue the curricula.
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Gautam BK, Henderson G. Laboratory Study of the Influence of Substrate Type and Temperature on the Exploratory Tunneling by Formosan Subterranean Termite. Insects 2012; 3:629-39. [PMID: 26466619 DOI: 10.3390/insects3030629] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/04/2012] [Revised: 06/19/2012] [Accepted: 06/19/2012] [Indexed: 11/17/2022]
Abstract
Using two-dimensional foraging arenas, laboratory tests were conducted to investigate the effect of soil type, soil moisture level and ambient temperature on the exploratory tunneling by Coptotermes formosanus Shiraki. In choice arenas consisting of two substrate types having two moisture levels each, and conducted at a constant temperature of 22 °C, a significantly greater proportion of termites aggregated in sand than in sandy loam. Similarly, the length of excavated tunnels was also increased in sand. In a given substrate, termite aggregation or tunnel length did not differ between 5% and 15% moisture levels. In no-choice tests, where three different substrates (sand, sandy loam and silt loam) were tested at two temperatures (22 °C and 28 °C), excavations were significantly greater in sand than either sandy loam or silt loam at 22 °C. Fewer primary tunnels were constructed in sandy loam than in sand and fewer branched tunnels than either in sand or silt loam. No significant difference in either tunnel length or number of primary or branched tunnels was found between these two temperatures.
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Arinana, Tsunoda K, Herliyana EN, Hadi YS. Termite-Susceptible Species of Wood for Inclusion as a Reference in Indonesian Standardized Laboratory Testing. Insects 2012; 3:396-401. [PMID: 26466532 DOI: 10.3390/insects3020396] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/17/2012] [Revised: 02/24/2012] [Accepted: 03/19/2012] [Indexed: 11/23/2022]
Abstract
Standardized laboratory testing of wood and wood-based products against subterranean termites in Indonesia (SNI 01.7207-2006) (SNI) has no requirement for the inclusion of a comparative reference species of wood (reference control). This is considered a weakness of the Indonesian standard. Consequently, a study was undertaken to identify a suitable Indonesian species of community wood that could be used as a reference control. Four candidate species of community woods: Acacia mangium, Hevea brasiliensis, Paraserianthes falcataria and Pinus merkusii were selected for testing their susceptibility to feeding by Coptotermes formosanus. Two testing methods (SNI and the Japanese standard method JIS K 1571-2004) were used to compare the susceptibility of each species of wood. Included in the study was Cryptomeria japonica, the reference control specified in the Japanese standard. The results of the study indicated that P. merkusii is a suitable reference species of wood for inclusion in laboratory tests against subterranean termites, conducted in accordance with the Indonesian standard (SNI 01.7207-2006).
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Hapukotuwa NK, Grace JK. Preferences of Coptotermes formosanus Shiraki and Coptotermes gestroi (Wasmann) (Blattodea: Rhinotermitidae) among Three Commercial Wood Species. Insects 2011; 2:499-508. [PMID: 26467829 DOI: 10.3390/insects2040499] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/13/2011] [Revised: 11/03/2011] [Accepted: 11/08/2011] [Indexed: 12/02/2022]
Abstract
The Formosan subterranean termite, Coptotermes formosanus Shiraki, and the Asian subterranean termite, Coptotermes gestroi (Wasmann), are both pests of wood in service in Hawaii and Florida. We conducted a laboratory study using method modified from those described in standard E1-09 of the American Wood Protection Association (AWPA 2009) to assess the termite resistance of three commercially available wood species used in regions of the USA where both termite species occur: Douglas fir, Pseudotsuga menziessii, southern yellow pine, Pinus spp. and redwood, Sequoia sempervirens. A multiple-choice (three-choice) assay was used for four weeks (28 days) in order to simulate field conditions of food choice and assess termite feeding preferences under 28 °C and 72–80% RH. 400 termites (360 workers: 40 soldiers) were released into each test jar. Five replicates and two controls of each wood species were used with each termite species. Termite mortality was recorded at the end of the test; and wood wafers were oven-dried and weighed before and after termite exposure to determine the mass loss due to termite feeding, and rated visually on a 0 (failure) to 10 (sound) scale. There were significant differences in mean mass loss values among the three wood species and between two termite species. The mean mass loss value for redwood was significantly lower than Douglas fir and southern yellow pine with both termite species. However, C. formosanus showed increased feeding on Douglas fir and southern yellow pine compared to C. gestroi.
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Hapukotuwa NK, Grace JK. Comparative Study of the Resistance of Six Hawaii-Grown Bamboo Species to Attack by the Subterranean Termites Coptotermes formosanus Shiraki and Coptotermes gestroi (Wasmann) (Blattodea: Rhinotermitidae). Insects 2011; 2:475-85. [PMID: 26467827 DOI: 10.3390/insects2040475] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/13/2011] [Revised: 10/25/2011] [Accepted: 10/26/2011] [Indexed: 11/30/2022]
Abstract
Bamboo is widely grown and utilized as a construction material around the world, particularly in the tropics. At present, there are about 70 bamboo species and varieties recorded from Hawaii. The objective of our study was to determine the relative resistance of six Hawaii-grown bamboo species to attack by Coptotermes formosanus Shiraki and Coptotermes gestroi (Wasmann). Four-week laboratory feeding trials were performed as described in standard E1-09 of the American Wood Protection Association (AWPA 2009). Samples of each of the six bamboo species were individually exposed to 200 termites (with 10% soldiers); and termite mortality, wood mass loss, and visual appearance of the samples (on a scale of 0–10) were recorded at the conclusion of the trail. Mean mass losses of the six species as a result of termite feeding ranged from 13–29%; with the two most resistant bamboo species, Gigantocholoa pseudoarundinacea and Bambusa oldhamii, demonstrating significantly greater resistance to termite attack than the most susceptible bamboo species, Guadua anguistifolia, with both termite species. Dendrocalamus brandisii, Dendrocalamus latiflorus, and Bambusa hirose were intermediate in their termite resistance. Overall, we observed very little difference in wood preference between C. formosanus and C. gestroi. Although bamboo is a very promising construction material, and species clearly differ in their susceptibility to termite attack, all six species evaluated in the present study would require additional protection for use under conditions of high termite pressure.
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Husseneder C, Ho HY, Blackwell M. Comparison of the bacterial symbiont composition of the formosan subterranean termite from its native and introduced range. Open Microbiol J 2010; 4:53-66. [PMID: 21347207 PMCID: PMC3040989 DOI: 10.2174/1874285801004010053] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2010] [Revised: 06/24/2010] [Accepted: 06/29/2010] [Indexed: 02/01/2023] Open
Abstract
We investigated the bacterial composition in the gut of Formosan subterranean termites (FST), Coptotermes formosanus Shiraki, collected from southern China (native range) vs. Louisiana, U. S. (introduced range) using 16S rRNA gene sequencing. Overall, we identified 213 bacteria ribotypes from thirteen phyla. The enemy release hypothesis could not be invoked to explain invasion success of FST since no pathogens were found among the bacterial gut community regardless of geographic origin. Invasion of new habitats did not significantly change the bacteria composition. Apparently, the tight co-evolutionary link between termites and their gut flora maintains a certain association of species and functional groups. Ribotype richness, bacteria diversity, and proportions of detected phyla were not influenced by geographic origin of FST samples; however, these parameters were affected by storage of the samples. Ethanol storage of termite samples (5 yrs) increased the relative proportions of gram-positive bacteria versus gram-negative bacteria.
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Affiliation(s)
- Claudia Husseneder
- Department of Entomology, Louisiana State University Agricultural Center, Baton Rouge, LA 70803, USA
| | - Huei-Yang Ho
- Department of Entomology, Louisiana State University Agricultural Center, Baton Rouge, LA 70803, USA
| | - Meredith Blackwell
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA 70803, USA
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Yu H, Gouge DH, Shapiro-Ilan DI. A novel strain of Steinernema riobrave (Rhabditida: Steinernematidae) possesses superior virulence to subterranean termites (Isoptera: Rhinotermitidae). J Nematol 2010; 42:91-95. [PMID: 22736844 PMCID: PMC3380470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2010] [Indexed: 06/01/2023] Open
Abstract
Subterranean termites are major global pests of wood structures and wood products. Among the most economically important subterranean termite species in the US are Heterotermes aureus, Reticulitermes flavipes, and Coptotermes formosanus. In prior studies, the entomopathogenic nematode, Steinernema riobrave strain 355, exhibited a high level of virulence to H. aureus compared with other nematode species. However, S. riobrave 355 was reported to be poorly or only moderately virulent to R. flavipes and C. formosanus, respectively. We hypothesized that other strains of S. riobrave may possess a high level of virulence to all three termite species. Under laboratory conditions we compared three novel strains of S. riobrave (3-8b, 7-12, and TP) with the 355 strain for virulence to H. aureus, R. flavipes, and C. formosanus workers. H. aureus was very susceptible to all the S. riobrave strains, and termites in all nematode treatments were dead after 4 d. The TP strain of S. riobrave caused greater mortality in R. flavipes and C. formosanus compared to the other nematode strains. Specifically, the TP strain caused 75% and 91% mortality in R. flavipes and C. formosanus, respectively, which was more than 300% and 70% higher than the mortality caused by other strains. Additional studies are warranted to determine the ability of S. riobrave (TP) to control the targeted termite species under field conditions.
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Affiliation(s)
- Hao Yu
- University of Arizona, MAC Experiment Station, 37860 West Smith-Enke Rd., Maricopa, AZ 85239, USA
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