Insecticide resistance governed by gut symbiosis in a rice pest,
            Cletus punctiger,
            under laboratory conditions

Resistance to toxins in insects is generally thought of as their own genetic trait, but recent studies have revealed that gut microorganisms could mediate resistance by detoxifying phytotoxins and man-made insecticides. By laboratory experiments, we here discovered a striking example of gut symbiont-mediated insecticide resistance in a serious rice pest, Cletus punctiger . The rice bug horizontally acquired fenitrothion-degrading Burkholderia through oral infection and housed it in midgut crypts. Fenitrothion-degradation test revealed that the gut-colonizing Burkholderia retains a high degrading activity of the organophosphate compound in the insect gut. This gut symbiosis remarkably increased resistance against fenitrothion treatment in the host rice bug. Considering that many stinkbug pests are associated with soil-derived Burkholderia , our finding strongly supports that a number of stinkbug species could gain resistance against insecticide simply by acquiring insecticide-degrading gut bacteria.

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Purine Biosynthesis, Biofilm Formation, and Persistence of an Insect-Microbe Gut Symbiosis

Applied and Environmental Microbiology ◽

10.1128/aem.00739-14 ◽

2014 ◽

Vol 80 (14) ◽

pp. 4374-4382 ◽

Cited By ~ 37

Author(s):

Jiyeun Kate Kim ◽

Jeong Yun Kwon ◽

Soo Kyoung Kim ◽

Sang Heum Han ◽

Yeo Jin Won ◽

...

Keyword(s):

Biofilm Formation ◽

Molecular Mechanisms ◽

Purine Biosynthesis ◽

Symbiotic Association ◽

Wild Type ◽

Content Type ◽

Secondary Messenger ◽

Infection Density ◽

Midgut Crypts ◽

Insect Gut

ABSTRACTTheRiptortus-Burkholderiasymbiotic system is an experimental model system for studying the molecular mechanisms of an insect-microbe gut symbiosis. When the symbiotic midgut ofRiptortus pedestriswas investigated by light and transmission electron microscopy, the lumens of the midgut crypts that harbor colonizingBurkholderiasymbionts were occupied by an extracellular matrix consisting of polysaccharides. This observation prompted us to search for symbiont genes involved in the induction of biofilm formation and to examine whether the biofilms are necessary for the symbiont to establish a successful symbiotic association with the host. To answer these questions, we focused onpurNandpurT, which independently catalyze the same step of bacterial purine biosynthesis. When we disruptedpurNandpurTin theBurkholderiasymbiont, the ΔpurNand ΔpurTmutants grew normally, and only the ΔpurTmutant failed to form biofilms. Notably, the ΔpurTmutant exhibited a significantly lower level of cyclic-di-GMP (c-di-GMP) than the wild type and the ΔpurNmutant, suggesting involvement of the secondary messenger c-di-GMP in the defect of biofilm formation in the ΔpurTmutant, which might operate via impaired purine biosynthesis. The host insects infected with the ΔpurTmutant exhibited a lower infection density, slower growth, and lighter body weight than the host insects infected with the wild type and the ΔpurNmutant. These results show that the function ofpurTof the gut symbiont is important for the persistence of the insect gut symbiont, suggesting the intricate biological relevance of purine biosynthesis, biofilm formation, and symbiosis.

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Insecticide resistance by a host-symbiont reciprocal detoxification

Nature Communications ◽

10.1038/s41467-021-26649-2 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Yuya Sato ◽

Seonghan Jang ◽

Kazutaka Takeshita ◽

Hideomi Itoh ◽

Hideaki Koike ◽

...

Keyword(s):

Insecticide Resistance ◽

Reverse Genetics ◽

Critical Role ◽

Insect Genome ◽

Bean Bug ◽

Gut Symbionts ◽

Insect Gut ◽

Powerful Strategy ◽

Detoxification Process

AbstractInsecticide resistance is one of the most serious problems in contemporary agriculture and public health. Although recent studies revealed that insect gut symbionts contribute to resistance, the symbiont-mediated detoxification process remains unclear. Here we report the in vivo detoxification process of an organophosphorus insecticide, fenitrothion, in the bean bug Riptortus pedestris. Using transcriptomics and reverse genetics, we reveal that gut symbiotic bacteria degrade this insecticide through a horizontally acquired insecticide-degrading enzyme into the non-insecticidal but bactericidal compound 3-methyl-4-nitrophenol, which is subsequently excreted by the host insect. This integrated “host-symbiont reciprocal detoxification relay” enables the simultaneous maintenance of symbiosis and efficient insecticide degradation. We also find that the symbiont-mediated detoxification process is analogous to the insect genome-encoded fenitrothion detoxification system present in other insects. Our findings highlight the capacity of symbiosis, combined with horizontal gene transfer in the environment, as a powerful strategy for an insect to instantly eliminate a toxic chemical compound, which could play a critical role in the human-pest arms race.

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Host–symbiont specificity determined by microbe–microbe competition in an insect gut

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1912397116 ◽

2019 ◽

Vol 116 (45) ◽

pp. 22673-22682 ◽

Cited By ~ 24

Author(s):

Hideomi Itoh ◽

Seonghan Jang ◽

Kazutaka Takeshita ◽

Tsubasa Ohbayashi ◽

Naomi Ohnishi ◽

...

Keyword(s):

Plant Pathogens ◽

Bacterial Species ◽

Bacterial Symbiont ◽

Human Pathogens ◽

Beneficial Effects ◽

Specific Host ◽

Microbial Symbiont ◽

Bean Bug ◽

Midgut Crypts ◽

Insect Gut

Despite the omnipresence of specific host–symbiont associations with acquisition of the microbial symbiont from the environment, little is known about how the specificity of the interaction evolved and is maintained. The bean bug Riptortus pedestris acquires a specific bacterial symbiont of the genus Burkholderia from environmental soil and harbors it in midgut crypts. The genus Burkholderia consists of over 100 species, showing ecologically diverse lifestyles, and including serious human pathogens, plant pathogens, and nodule-forming plant mutualists, as well as insect mutualists. Through infection tests of 34 Burkholderia species and 18 taxonomically diverse bacterial species, we demonstrate here that nonsymbiotic Burkholderia and even its outgroup Pandoraea could stably colonize the gut symbiotic organ and provide beneficial effects to the bean bug when inoculated on aposymbiotic hosts. However, coinoculation revealed that the native symbiont always outcompeted the nonnative bacteria inside the gut symbiotic organ, explaining the predominance of the native Burkholderia symbiont in natural bean bug populations. Hence, the abilities for colonization and cooperation, usually thought of as specific traits of mutualists, are not unique to the native Burkholderia symbiont but, to the contrary, competitiveness inside the gut is a derived trait of the native symbiont lineage only and was thus critical in the evolution of the insect gut symbiont.

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Bio-ecology of Slender Black Rice Bug, Paraeucosmetus pallicornis in South Sulawesi

KnE Life Sciences ◽

10.18502/kls.v2i6.1087 ◽

2017 ◽

Vol 2 (6) ◽

pp. 648

Author(s):

Rahmini Rahmini ◽

Dede Munawar ◽

Wasis Senoaji ◽

Yuliantoro Baliadi

Keyword(s):

Rice Field ◽

Light Trap ◽

Pitfall Trap ◽

Rice Grain ◽

Black Rice ◽

South Sulawesi ◽

Rice Bug ◽

Rice Pest ◽

Yellow Sticky Trap ◽

Planting Season

A study on the bio-ecology of slender black rice bug, Paraeucosmetus pallicornis, was conducted in the research farm of Lolit Tungro, Lanrang, South Sulawesi, Indonesia. This pest is considered as new rice pest, attacking rice plant especially during generative stage. This pest inserts its stylet and then sucks the sap of the developing rice grain. Light trap was used to catch this pest. Yellow sticky trap and pitfall trap were used to determine the insect population and to find out when the pest infests the plant. Fifteen yellow sticky traps were set diagonally on rice field, and 10 pitfall traps were placed on the ground. The traps were placed on three plots as replication. On the first week of the study, it was found that the number of captured insects from the light trap during harvesting was 193. On the 2nd to 4th weeks, during fallow stubble, the captured insects were 135 -740. In the early of May, the field started to be ploughed as preparation for the next planting season. As the result, the number of insects captured decreased to 53 – 152 insects. The 2013 planting season was started in June. During this period, the bugs captured were only 1 – 3. This indicates that the bugs have already moved or migrated out of the rice field. The average number of eggs laid were 53.3 (1 pair), 124.8 (2 pairs), 142.5 (3 pairs), 202.3 (4 pairs), and 284 (5 pairs) and the average of hatch rate was 29.9%. The damaged rice grain was 38% grains/panicle (ranged 24.2-57.4%). This level of damage indicates that the P. pallicornis contributes to the reduction of rice yield. Keywords: Paraeucosmetus pallicornis, rice pest

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Imported insecticide resistance in diamondback moth

New Zealand Plant Protection ◽

10.30843/nzpp.2000.53.3617 ◽

2000 ◽

Vol 53 ◽

pp. 83-86 ◽

Cited By ~ 1

Author(s):

D.G. Voice ◽

R.B. Chapman

Keyword(s):

Insecticide Resistance ◽

Plutella Xylostella ◽

Laboratory Experiments ◽

Diamondback Moth ◽

Hybrid Strain ◽

Australian Population ◽

Susceptible Population ◽

Susceptible Populations

Laboratory experiments were conducted to determine whether resistance in an Australian population of diamondback moth could be conferred to a local susceptible population of diamondback moth (Plutella xylostella) Bioassays with larvae showed a 715fold difference in response at the LC50 to alphacypermethrin between the resistant imported and local susceptible populations The response of a hybrid strain from these populations displayed a lower level of resistance and a backcross of hybrids with the parents an even lower level of resistance The hybrid strain did not suffer any fitness disadvantage when compared with the parents

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Covering of cometary nucleus by refractory crust and its evolution into asteroid-like body

International Astronomical Union Colloquium ◽

10.1017/s0252921100031675 ◽

1999 ◽

Vol 173 ◽

pp. 365-370

Author(s):

Kh.I. Ibadinov

Keyword(s):

Laboratory Experiments ◽

Cometary Nucleus ◽

Sublimation Rate ◽

Cometary Nuclei ◽

Short Period Comet ◽

Short Period ◽

Brightness Decrease ◽

Crust Thickness ◽

Ice Sublimation ◽

Period Comet

AbstractFrom the established dependence of the brightness decrease of a short-period comet dependence on the perihelion distance of its orbit it follows that part of the surface of these cometary nuclei gradually covers by a refractory crust. The results of cometary nucleus simulation show that at constant insolation energy the crust thickness is proportional to the square root of the insolation time and the ice sublimation rate is inversely proportional to the crust thickness. From laboratory experiments resulted the thermal regime, the gas productivity of the nucleus, covering of the nucleus by the crust, and the tempo of evolution of a short-period comet into the asteroid-like body studied.

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High Voltage Electron Microscopy of Viral Inclusion Bodies

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s1431927600002117 ◽

1980 ◽

Vol 38 ◽

pp. 486-487 ◽

Cited By ~ 1

Author(s):

H.M. Mazzone ◽

W.F. Engler ◽

G. Wray ◽

A. Szirmae ◽

J. Conroy ◽

...

Keyword(s):

New York ◽

Environmental Protection Agency ◽

Inclusion Bodies ◽

Host Cells ◽

High Voltage Electron Microscopy ◽

Voltage Electron ◽

Viral Particles ◽

Pest Insects ◽

Viral Inclusion ◽

Insect Gut

Viral inclusion bodies isolated from infected pest insects are being evaluated by the U.S. Dept. of Agriculture as biological insecticides against their hosts. Our research on these inclusion bodies constitutes part of an effort to support their approval by the Environmental Protection Agency as insect control agents. The inclusion bodies in this study are polyhedral in shape and contain rod-shaped viral particles. When ingested by pest insects, the inclusion bodies are broken down in the insect gut and release the viral particles which infect and multiply in the nuclei of host cells. These viruses are termed nucleopolyhedrosis viruses (NPV) and are representatives of the baculoviruses (Wildy, P. 1971 IN J.L. Melnick, ed., Monographs in Virology, vol. 5, S.Karger, New York).

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When Does Voice Have to be More Than Only Listening? Procedural Justice Effects as a Function of Confident Leadership

Journal of Personnel Psychology ◽

10.1027/1866-5888/a000011 ◽

2010 ◽

Vol 9 (2) ◽

pp. 69-78 ◽

Cited By ~ 8

Author(s):

David De Cremer ◽

Maarten Wubben

Keyword(s):

Procedural Justice ◽

Interaction Effect ◽

Laboratory Experiments ◽

Negative Emotions

The present research examined how voice procedures and leader confidence affect participants’ negative emotions and willingness to withdraw. It was predicted that receiving voice would be valued out of instrumental concerns, but only when the enacting leader was high in confidence. Two laboratory experiments indeed showed an interaction between type of voice (pre-decisional vs. post-decisional) and leader’s confidence (low vs. high) on participants’ negative emotions and willingness to withdraw. In particular, post-decision voice only led to more negative responses than did pre-decision voice when the enacting leader was high in confidence. Negative emotions mediated this interaction effect of type of voice on willingness to withdraw. Implications for integrating the leadership and procedural justice literatures are discussed.

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