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Li WX, Chen JX, Zhang CC, Luo MS, Zhang WQ. Functional analysis of Ornithine decarboxylase in manipulating the wing dimorphism in Nilaparvata lugens (Stål) (Hemiptera: Delphacidae). JOURNAL OF INSECT PHYSIOLOGY 2024; 152:104587. [PMID: 38043786 DOI: 10.1016/j.jinsphys.2023.104587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Revised: 11/28/2023] [Accepted: 11/28/2023] [Indexed: 12/05/2023]
Abstract
The brown planthopper (BPH, Nilaparvata lugens), a major insect pest of rice, can make a shift in wing dimorphism to adapt to complex external environments. Our previous study showed that NlODC (Ornithine decarboxylase in N. lugens) was involved in wing dimorphism of the brown planthopper. Here, further experiments were conducted to reveal possible molecular mechanism of NlODC in manipulating the wing dimorphism. We found that the long-winged rate (LWR) of BPH was significantly reduced after RNAi of NlODC or injection of DFMO (D, L-α-Difluoromethylornithine), and LWR of males and females significantly decreased by 21.7% and 34.6%, respectively. Meanwhile, we also examined the contents of three polyamines under DFMO treatment and found that the contents of putrescine and spermidine were significantly lower compared to the control. After 3rd instar nymphs were injected with putrescine and spermidine, LWR was increased significantly in both cases, and putrescine was a little bit more effective, with 5.6% increase in males and 11.4% in females. Three days after injection of dsNlODC, injection of putrescine and spermidine rescued LWR to the normal levels. In the regulation of wing differentiation in BPH, NlODC mutually antagonistic to NlAkt may act through other signaling pathways rather than the classical insulin signaling pathway. This study illuminated a physiological function of an ODC gene involved in wing differentiation in insects, which could be a potential target for pest control.
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Affiliation(s)
- Wan-Xue Li
- State Key Laboratory of Biocontrol and School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Jing-Xiang Chen
- State Key Laboratory of Biocontrol and School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Chuan-Chuan Zhang
- State Key Laboratory of Biocontrol and School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Min-Shi Luo
- State Key Laboratory of Biocontrol and School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China
| | - Wen-Qing Zhang
- State Key Laboratory of Biocontrol and School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, China.
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2
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Krongauz DL, Ayali A, Kaminka GA. Vision-based collective motion: A locust-inspired reductionist model. PLoS Comput Biol 2024; 20:e1011796. [PMID: 38285716 PMCID: PMC10852344 DOI: 10.1371/journal.pcbi.1011796] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Revised: 02/08/2024] [Accepted: 01/03/2024] [Indexed: 01/31/2024] Open
Abstract
Naturally occurring collective motion is a fascinating phenomenon in which swarming individuals aggregate and coordinate their motion. Many theoretical models of swarming assume idealized, perfect perceptual capabilities, and ignore the underlying perception processes, particularly for agents relying on visual perception. Specifically, biological vision in many swarming animals, such as locusts, utilizes monocular non-stereoscopic vision, which prevents perfect acquisition of distances and velocities. Moreover, swarming peers can visually occlude each other, further introducing estimation errors. In this study, we explore necessary conditions for the emergence of ordered collective motion under restricted conditions, using non-stereoscopic, monocular vision. We present a model of vision-based collective motion for locust-like agents: elongated shape, omni-directional visual sensor parallel to the horizontal plane, and lacking stereoscopic depth perception. The model addresses (i) the non-stereoscopic estimation of distance and velocity, (ii) the presence of occlusions in the visual field. We consider and compare three strategies that an agent may use to interpret partially-occluded visual information at the cost of the computational complexity required for the visual perception processes. Computer-simulated experiments conducted in various geometrical environments (toroidal, corridor, and ring-shaped arenas) demonstrate that the models can result in an ordered or near-ordered state. At the same time, they differ in the rate at which order is achieved. Moreover, the results are sensitive to the elongation of the agents. Experiments in geometrically constrained environments reveal differences between the models and elucidate possible tradeoffs in using them to control swarming agents. These suggest avenues for further study in biology and robotics.
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Affiliation(s)
| | - Amir Ayali
- School of Zoology and Sagol School of Neuroscience, Tel Aviv University, Israel
| | - Gal A. Kaminka
- Computer Science Department, Bar-Ilan Univeristy, Israel
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3
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Arafat EA, El-Samad LM, Moussian B, Hassan MA. Insights into spermatogenesis in the migratory locust, Locusta migratoria (Linnaeus, 1758) (Orthoptera: Acrididae), following histological and ultrastructural features of the testis. Micron 2023; 172:103502. [PMID: 37422968 DOI: 10.1016/j.micron.2023.103502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 06/24/2023] [Accepted: 06/24/2023] [Indexed: 07/11/2023]
Abstract
The migratory locust, Locusta migratoria (Linnaeus, 1758), is one of the most destructive agricultural pests globally, and this species is particularly localized in several regions of Egypt. However, so far, very little attention has been paid to the characteristics of the testes. Furthermore, spermatogenesis requires careful analysis to characterize and track developmental episodes. We thus investigated, for the first time, the histological and ultrastructural properties of the testis in L. migratoria employing a light microscope, a scanning electron microscope (SEM), and a transmission electron microscope (TEM). Our results revealed that the testis comprises several follicles, emerging with distinct outer surface wrinkle patterns for each follicle throughout the length of the follicular wall. Furthermore, histological examination of the follicles showed that each has three developmental zones. Each zone has cysts with characteristic spermatogenic elements, beginning with the spermatogonia at the distal end of each follicle and ending with the spermatozoa at the proximal end. Moreover, spermatozoa are arranged in spermatozoa bundles called spermatodesms. Overall, this research provides novel insights into the structure of the testes of L. migratoria, which will significantly contribute to formulating effective pesticides against locusts.
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Affiliation(s)
- Esraa A Arafat
- Department of Zoology, Faculty of Science, Alexandria University, Egypt
| | - Lamia M El-Samad
- Department of Zoology, Faculty of Science, Alexandria University, Egypt
| | - Bernard Moussian
- Université Côte d'Azur, INRAE, CNRS, Institut Sophia Agrobiotech, France
| | - Mohamed A Hassan
- Protein Research Department, Genetic Engineering and Biotechnology Research Institute (GEBRI), City of Scientific Research and Technological Applications (SRTA-City), New Borg El-Arab City, 21934 Alexandria, Egypt.
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4
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Li X, Karpac J. Adaptive physiology drives ageing plasticity in locusts. Nat Ecol Evol 2023:10.1038/s41559-023-02052-6. [PMID: 37156890 DOI: 10.1038/s41559-023-02052-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Affiliation(s)
- Xiaotong Li
- Department of Cell Biology and Genetics, Texas A&M University, School of Medicine, Bryan, TX, USA
| | - Jason Karpac
- Department of Cell Biology and Genetics, Texas A&M University, School of Medicine, Bryan, TX, USA.
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5
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Maeno KO, Piou C, Leménager N. Egg size-dependent embryonic development in the desert locust, Schistocerca gregaria. JOURNAL OF INSECT PHYSIOLOGY 2023; 145:104467. [PMID: 36528090 DOI: 10.1016/j.jinsphys.2022.104467] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 09/26/2022] [Accepted: 12/11/2022] [Indexed: 06/17/2023]
Abstract
Phenotypic plasticity in body size is a product of modification of the developmental pathway. Although hatchlings of the desert locust, Schistocerca gregaria, show egg size-dependent plasticity in body size, it remains unclear how embryogenesis during egg development regulates final embryonic body size. To determine the developmental pathway causing body size variation at hatching, we examined egg and embryonic development at the early, middle, and late egg developmental stages in S. gregaria by comparing small and large eggs. Crowd-reared females produced larger eggs than isolated-reared females. The daily egg developmental rate was similar between small and large eggs: eggs dramatically absorbed external water after days 3 to 7 and nearly doubled the initial egg weight at the late stage of day 12. Morphological measurements of eggs and embryos at different days after oviposition revealed that large eggs were longer than small eggs throughout developmental stages. However, embryo length was similar between small and large eggs at the early stage (anatrepsis). Embryos begin to absorb yolk into their bodies after blastokinesis. The size of large-egg embryos increased significantly from the middle stage (katatrepsis) due to absorption of more yolk than small eggs. Egg length and embryo length were conspicuously larger in large eggs than in small eggs on day 12 of late katatrepsis. These results suggest that egg size did not influence the egg developmental rate and initial embryo size. Large eggs had more yolk and space, resulting in larger final embryos than small eggs. The amount of yolk and size of eggshells during katatrepsis could play a key role in determining hatchling body size in S. gregaria.
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Affiliation(s)
- Koutaro Ould Maeno
- Japan International Research Center for Agricultural Sciences (JIRCAS), Livestock and Environment Division, Ohwashi 1-1, Tsukuba, Ibaraki 305-8686, Japan.
| | - Cyril Piou
- CIRAD, UMR CBGP, INRAE, Institut Agro, IRD, Université Montpellier, F-34398 Montpellier, France
| | - Nicolas Leménager
- CIRAD, UMR CBGP, INRAE, Institut Agro, IRD, Université Montpellier, F-34398 Montpellier, France
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6
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Bleichman I, Yadav P, Ayali A. Visual processing and collective motion-related decision-making in desert locusts. Proc Biol Sci 2023; 290:20221862. [PMID: 36651041 PMCID: PMC9845972 DOI: 10.1098/rspb.2022.1862] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Collectively moving groups of animals rely on the decision-making of locally interacting individuals in order to maintain swarm cohesion. However, the complex and noisy visual environment poses a major challenge to the extraction and processing of relevant information. We addressed this challenge by studying swarming-related decision-making in desert locust last-instar nymphs. Controlled visual stimuli, in the form of random dot kinematograms, were presented to tethered locust nymphs in a trackball set-up, while monitoring movement trajectory and walking parameters. In a complementary set of experiments, the neurophysiological basis of the observed behavioural responses was explored. Our results suggest that locusts use filtering and discrimination upon encountering multiple stimuli simultaneously. Specifically, we show that locusts are sensitive to differences in speed at the individual conspecific level, and to movement coherence at the group level, and may use these to filter out non-relevant stimuli. The locusts also discriminate and assign different weights to different stimuli, with an observed interactive effect of stimulus size, relative abundance and motion direction. Our findings provide insights into the cognitive abilities of locusts in the domain of decision-making and visual-based collective motion, and support locusts as a model for investigating sensory-motor integration and motion-related decision-making in the intricate swarm environment.
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Affiliation(s)
| | - Pratibha Yadav
- School of Zoology, Tel Aviv University, 6997801 Israel,Sagol School of Neuroscience, Tel Aviv University, 6997801 Israel
| | - Amir Ayali
- School of Zoology, Tel Aviv University, 6997801 Israel,Sagol School of Neuroscience, Tel Aviv University, 6997801 Israel
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7
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Guo N, Ma H, Han H, Yan F, Gao H, Zhang Y, Gao S. Phenotypic and Differential Gene Expression Analyses of Phase Transition in Oedaleus asiaticus under High-Density Population Stress. INSECTS 2022; 13:1034. [PMID: 36354858 PMCID: PMC9697361 DOI: 10.3390/insects13111034] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/09/2022] [Revised: 11/02/2022] [Accepted: 11/07/2022] [Indexed: 06/16/2023]
Abstract
The high-density-dependent phase change from solitary to gregarious individuals in locusts is a typical example of phenotypic plasticity. However, the underlying molecular mechanism is not clear. In this study, first, Oedaleus asiaticus were treated with high-density population stress and then analyzed by Illumina sequencing on days 1, 3, 5, and 7 of the body color change to identify the stage-specific differentially expressed genes (DEGs). The KEGG pathway enrichment analysis of the identified DEGs revealed their role in metabolic pathways. Furthermore, the expression patterns of the nine key DEGs were studied in detail; this showed that the material change in locusts began on the third day of the high-density treatment, with the number of DEGs being the largest, indicating the importance of this period in the phase transition. In addition, the phenotypic change involved several key genes of important regulatory pathways, possibly working in a complex network. Phenotypic plasticity in locusts is multifactorial, involving multilevel material network interactions. This study improves the mechanistic understanding of phenotypic variation in insects at the genetic level.
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Affiliation(s)
- Na Guo
- Institute of Grassland Research, Chinese Academy of Agricultural Science, Hohhot 010010, China
| | - Hongyue Ma
- Research Center for Grassland Entomology, Inner Mongolia University for Nationalities, Tongliao 028000, China
| | - Haibin Han
- Institute of Grassland Research, Chinese Academy of Agricultural Science, Hohhot 010010, China
| | - Feng Yan
- Forest Pest Management and Quarantine Station of Ordos, Ordos 017010, China
| | - Haiyan Gao
- Institute of Grassland Research, Chinese Academy of Agricultural Science, Hohhot 010010, China
| | - Yuanyuan Zhang
- Institute of Grassland Research, Chinese Academy of Agricultural Science, Hohhot 010010, China
| | - Shujing Gao
- Institute of Grassland Research, Chinese Academy of Agricultural Science, Hohhot 010010, China
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8
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Georgiou F, Buhl C, Green JEF, Lamichhane B, Thamwattana N. Modelling foraging competition between solitarious and gregarious organisms in increasingly heterogeneous environments. JOURNAL OF INSECT PHYSIOLOGY 2022; 143:104443. [PMID: 36208774 DOI: 10.1016/j.jinsphys.2022.104443] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 09/17/2022] [Accepted: 09/29/2022] [Indexed: 06/16/2023]
Abstract
Density dependent phase polyphenism is the exhibiting of two or more distinct phenotypes from a single genotype depending on local population density. The most well known insect to exhibit this phenomenon is the locust, with whom the profound effect on behaviour leads to the classification of the two phases; solitarious, where locusts actively avoid other locusts, and gregarious, where locusts are strongly attracted to other locusts. It has been shown that food distributions at both small and large scales have an effect on the process of gregarisation. While gregarisation offers advantages, such as greater predator avoidance, the relationship between phase polyphenism and potential foraging benefits is still not fully understood. In this paper, we explore the effect of gregarisation on foraging within increasingly heterogeneous environments using a partial differential equation model. We first consider a single two dimensional simulation of a spatially heterogeneous environment to understand the mechanics of gregarious/solitarious foraging. We then look at the steady state foraging advantage (measured as the ratio of per-capita contact with food) in environments ranging from homogeneous to very spatially heterogeneous. Finally, we perform a parameter sensitivity analysis to find which model parameters have the greatest effect on foraging advantage. We find that during the aggregation stage, prior to the onset of marching (which we do not model here), in increasingly heterogeneous food environments it is better to be gregarious than solitarious. In addition, we find that this is intrinsic to the gregarious/solitarious behavioural dynamic as it occurs almost regardless of the model parameters. That is to say, it doesn't matter how fast the organisms disperse or how strong their long range interactions as long as there is the solitarious/gregarious behaviour the gregarious foraging advantage will exist.
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Affiliation(s)
- F Georgiou
- School of Mathematical and Physical Sciences, University of Newcastle, Callaghan, NSW 2308, Australia.
| | - Camille Buhl
- School of Agriculture, Food and Wine, University of Adelaide, Adelaide, SA 5005, Australia
| | - J E F Green
- School of Mathematical Sciences, University of Adelaide, Adelaide, SA 5005, Australia
| | - B Lamichhane
- School of Mathematical and Physical Sciences, University of Newcastle, Callaghan, NSW 2308, Australia
| | - N Thamwattana
- School of Mathematical and Physical Sciences, University of Newcastle, Callaghan, NSW 2308, Australia
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9
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Does space matter? Estimation and evaluation of required space for commercial mass culture of grasshoppers (Acridoidea: Orthoptera). PLoS One 2022; 17:e0265664. [PMID: 35657954 PMCID: PMC9165845 DOI: 10.1371/journal.pone.0265664] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 03/04/2022] [Indexed: 11/19/2022] Open
Abstract
A space-dependent mortality assay was performed on thirty-one short-horned adult grasshopper species (Acridoidea: Orthoptera) to estimate the space required for mass culture of acridids in captivity. Our findings show that acridids have a multidimensional mortality mode at different densities. The correlations between density and mortality of acridids in rearing units follow a sigmoidal curve. Acridid mortality significantly increases with individual numbers up to a threshold, after which mortality does not change even if the density increases further. A log-logistic sigmoidal function expresses the dose (density)-response (mortality) relationship in the majority of acridid species. Mortality of acridids at variable densities does not necessarily correspond with the body-mass of the insects, indicating that mortality is a body-mass independent event. As a ready reference, a utility chart has been prepared, providing the necessary conversion factor for estimating space for a given number of acridids. The present information will be helpful for commercial grasshopper farming in captivity.
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Lavy O, Lewin‐Epstein O, Bendett Y, Gophna U, Gefen E, Hadany L, Ayali A. Microbiome‐related aspects of locust density‐dependent phase transition. Environ Microbiol 2022; 24:507-516. [DOI: 10.1111/1462-2920.15883] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Revised: 11/16/2021] [Accepted: 12/21/2021] [Indexed: 01/04/2023]
Affiliation(s)
- Omer Lavy
- School of Zoology Tel Aviv University Tel Aviv Israel
| | - Ohad Lewin‐Epstein
- Department of Molecular Biology and Ecology of Plants Tel Aviv University Tel Aviv Israel
| | - Yonatan Bendett
- Department of Molecular Biology and Ecology of Plants Tel Aviv University Tel Aviv Israel
| | - Uri Gophna
- Shmunis School of Biomedicine and Cancer Research Tel Aviv University Tel Aviv Israel
| | - Eran Gefen
- Department of Biology University of Haifa – Oranim Kiryat Tivon Israel
| | - Lilach Hadany
- Department of Molecular Biology and Ecology of Plants Tel Aviv University Tel Aviv Israel
| | - Amir Ayali
- School of Zoology Tel Aviv University Tel Aviv Israel
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11
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Piou C, Zagaglia G, Medina HE, Trumper E, Rojo Brizuela X, Maeno KO. Band movement and thermoregulation in Schistocerca cancellata. JOURNAL OF INSECT PHYSIOLOGY 2022; 136:104328. [PMID: 34826390 DOI: 10.1016/j.jinsphys.2021.104328] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 09/11/2021] [Accepted: 11/19/2021] [Indexed: 06/13/2023]
Abstract
At high density, juvenile locusts create marching hopper bands. Understanding the roles of temperature and vegetation on the movement of these bands shall allow to better forecast and control them. Following a hopper band in North Argentina in November 2019, we explored the thermoregulation behaviours of the South American locust, Schistocerca cancellata. Gut-content samples informed about the feeding status at different time of the day. Hoppers' body temperature was above cold air temperature in the mornings during basking and group-basking activities and before the onset of marching behaviour. Marching by walking or hopping was dominant at body temperatures close to 40 °C. Jumping, stilting, shading and perching on plants were seen as thermoregulatory behaviours to avoid ground temperatures above 50 °C. Feeding was observed throughout the day with continuous high gut contents despite an intermittent pattern of feeding-resting-marching. Speed and daily travelled distance of the front of the hopper band was depending on the type of encountered vegetation. Daily behavioural patterns, thermoregulatory behaviours, walking speed and daily travelled distances of S. cancellata were similar to the ones observed for the Desert locust, S. gregaria, in Africa. High air temperatures recorded during the observation times could explain the continuous feeding patterns. These species may have evolved behaviours of alternating consuming a bit and marching as a migration strategy to avoid staying where no food is available after the havoc left behind large hopper bands. Recommendations made for the control of Desert locust hopper bands can be extended to South American locust ones.
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Affiliation(s)
- Cyril Piou
- CIRAD, UMR CBGP, Montpellier, France; CBGP, CIRAD, INRA, IRD, SupAgro, Univ. Montpellier, Montpellier, France.
| | - Gustavo Zagaglia
- SENASA, Servicio Nacional de Sanidad y Calidad Agroalimentaria, Argentina
| | - Hector E Medina
- SENASA, Servicio Nacional de Sanidad y Calidad Agroalimentaria, Argentina
| | | | - Ximena Rojo Brizuela
- Ministerio de Desarrollo Económico y Producción de la Provincia Jujuy, Argentina
| | - Koutaro Ould Maeno
- Japan International Research Center for Agricultural Sciences (JIRCAS), Livestock and Environment Division, Ohwashi 1-1, Tsukuba, Ibaraki 305-8686, Japan
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12
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Maeno KO, Piou C, Ghaout S. Allocation of more reproductive resource to egg size rather than clutch size of gregarious desert locust (Schistocerca gregaria) through increasing oogenesis period and oosorption rate. JOURNAL OF INSECT PHYSIOLOGY 2022; 136:104331. [PMID: 34838517 DOI: 10.1016/j.jinsphys.2021.104331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 08/24/2021] [Accepted: 11/19/2021] [Indexed: 06/13/2023]
Abstract
The desert locust, Schistocerca gregaria, shows a density-dependent reproductive trade-off by laying fewer but larger eggs in crowded conditions (gregarious phase) than in isolated conditions (solitarious phase). However, the physiological mechanisms controlling reproductive resource allocation remain unclear. We examined how egg production processes, including ovulation timing (i.e., oogenesis period), oocyte and ovarian growth rates, and oosorption rate (resorbing developing terminal oocytes), regulate reproductive outputs (egg biomass per clutch, egg size, and clutch size) during a reproductive cycle in S. gregaria by rearing them either under isolated or crowded conditions. We observed a common density-dependent negative correlation between egg size and clutch size, with no significant difference in egg biomass between the two rearing conditions. Dissection of female locusts after different days of oviposition revealed that the daily oocyte growth rate was almost similar between the two rearing conditions, but crowd-reared females ovulated later than isolated-reared ones, resulting in further oocyte growth in the former. Terminal oocytes were renewed by previous penultimate oocytes at the onset of a new reproductive cycle, and oosorption mainly occurred at an early stage in both rearing conditions; however, crowd-reared locusts displayed higher levels of oosorption compared to their isolated-reared counterparts. Crowding induced a high oosorption rate, resulting in a reduced clutch size and a prolonged oogenesis period, which in turn allowed oocytes to intake more yolk, which was probably recycled via oosorption. These results suggest that the length of the oogenesis period and oosorption rate are manipulated by maternal density, and these physiological modifications interactively regulate reproductive trade-off in S. gregaria.
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Affiliation(s)
- Koutaro Ould Maeno
- Japan International Research Center for Agricultural Sciences (JIRCAS), Livestock and Environment Division, Ohwashi 1-1, Tsukuba, Ibaraki 305-8686, Japan.
| | - Cyril Piou
- CIRAD, UMR CBGP, INRAE, Institut Agro, IRD, Université Montpellier, F-34398 Montpellier, France; Ibn Zohr University, Agadir, Morocco; Centre National de Lutte Antiacridienne (CNLAA), Aït-Melloul, BP 125, Inezgane, Agadir, Morocco
| | - Saïd Ghaout
- Centre National de Lutte Antiacridienne (CNLAA), Aït-Melloul, BP 125, Inezgane, Agadir, Morocco
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13
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Couzin-Fuchs E, Ayali A. The social brain of 'non-eusocial' insects. CURRENT OPINION IN INSECT SCIENCE 2021; 48:1-7. [PMID: 33933684 DOI: 10.1016/j.cois.2021.04.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 04/19/2021] [Accepted: 04/20/2021] [Indexed: 06/12/2023]
Abstract
Decisions are seldom entirely devoid of social influence. Even in organisms that have traditionally been considered non-social, the social environment plays an important role in mediating behavior. Here we review the current knowledge regarding the neural basis of social behaviors in non-eusocial insects, with a particular focus on fruit flies, cockroaches and locusts. Each are shown to offer valuable, and complementary, insights into how social behavior is mediated at the neural level. The presented studies demonstrate that social cues, which are integrated in primary sensory areas, exert a considerable influence on behavior. Further studies with these models, and others, will provide important insights into the diversity of social behaviors, and into the way that these are encoded in dedicated brain and neuronal structures.
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Affiliation(s)
- Einat Couzin-Fuchs
- Department of Biology, University of Konstanz, 78457 Konstanz, Germany; Centre for the Advanced Study of Collective Behaviour, University of Konstanz, 78464 Konstanz, Germany.
| | - Amir Ayali
- School of Zoology, Tel Aviv University, 6997801, Israel; Sagol School of Neuroscience, Tel Aviv University, 6997801, Israel
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14
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Density-dependent mating behaviors reduce male mating harassment in locusts. Proc Natl Acad Sci U S A 2021; 118:2104673118. [PMID: 34635592 PMCID: PMC8594575 DOI: 10.1073/pnas.2104673118] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/24/2021] [Indexed: 11/18/2022] Open
Abstract
Male mating harassment may occur when females and males do not have the same mating objectives. Communal animals need to manage the costs of male mating harassment. Here, we demonstrate how desert locusts in dense populations reduce such conflicts through behaviors. In transient populations (of solitarious morphology but gregarious behavior), we found that nongravid females occupied separate sites far from males and were not mating, whereas males aggregated on open ground (leks), waiting for gravid females to enter the lekking sites. Once a male mounted a gravid female, no other males attacked the pair; mating pairs were thereby protected during the vulnerable time of oviposition. In comparison, solitarious locusts displayed a balanced sex ratio in low-density populations, and females mated irrespective of their ovarian state. Our results indicate that the mating behaviors of desert locusts are density dependent and that sex-biased behavioral group separation may minimize the costs of male mating harassment and competition.
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Chapuis M, Pélissié B, Piou C, Chardonnet F, Pagès C, Foucart A, Chapuis E, Jourdan‐Pineau H. Additive genetic variance for traits least related to fitness increases with environmental stress in the desert locust, Schistocerca gregaria. Ecol Evol 2021; 11:13930-13947. [PMID: 34707829 PMCID: PMC8525110 DOI: 10.1002/ece3.8099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2021] [Revised: 08/19/2021] [Accepted: 08/24/2021] [Indexed: 11/12/2022] Open
Abstract
Under environmental stress, previously hidden additive genetic variation can be unmasked and exposed to selection. The amount of hidden variation is expected to be higher for life history traits, which strongly correlate to individual fitness, than for morphological traits, in which fitness effects are more ambiguous. However, no consensual pattern has been recovered yet, and this idea is still debated in the literature. Here, we hypothesize that the classical categorization of traits (i.e., life history and morphology) may fail to capture their proximity to fitness. In the desert locust, Schistocerca gregaria, a model organism for the study of insect polyphenism, we quantified changes in additive genetic variation elicited by lifetime thermal stress for ten traits, in which evolutionary significance is known. Irrespective of their category, traits under strong stabilizing selection showed genetic invariance with environmental stress, while traits more loosely associated with fitness showed a marked increase in additive genetic variation in the stressful environment. Furthermore, traits involved in adaptive phenotypic plasticity (growth compensation) showed either no change in additive genetic variance or a change of moderate magnitude across thermal environments. We interpret this mitigated response of plastic traits in the context of integrated evolution to adjust the entire phenotype in heterogeneous environments (i.e., adaptiveness of initial plasticity, compromise of phenotypic compensation with stress, and shared developmental pathway). Altogether, our results indicate, in agreement with theoretical expectations, that environmental stress can increase available additive genetic variance in some desert locust traits, but those closely linked to fitness are largely unaffected. Our study also highlights the importance of assessing the proximity to fitness of a trait on a case-by-case basis and in an ecologically relevant context, as well as considering the processes of canalization and plasticity, involved in the control of phenotypic variation.
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Affiliation(s)
- Marie‐Pierre Chapuis
- CIRADCBGPMontpellierFrance
- CBGPCIRADMontpellier SupAgroINRAIRDUniv MontpellierMontpellierFrance
| | - Benjamin Pélissié
- CIRADCBGPMontpellierFrance
- CBGPCIRADMontpellier SupAgroINRAIRDUniv MontpellierMontpellierFrance
- Department of BiologyUniversity of Nebraska at KearneyKearneyNebraskaUSA
| | - Cyril Piou
- CIRADCBGPMontpellierFrance
- CBGPCIRADMontpellier SupAgroINRAIRDUniv MontpellierMontpellierFrance
| | - Floriane Chardonnet
- CIRADCBGPMontpellierFrance
- CBGPCIRADMontpellier SupAgroINRAIRDUniv MontpellierMontpellierFrance
| | | | - Antoine Foucart
- CIRADCBGPMontpellierFrance
- CBGPCIRADMontpellier SupAgroINRAIRDUniv MontpellierMontpellierFrance
| | - Elodie Chapuis
- MIVEGECUniversité de MontpellierCNRSIRDMontpellierFrance
- CIRADUMR PVBMTSaint‐PierreFrance
| | - Hélène Jourdan‐Pineau
- CIRADCBGPMontpellierFrance
- CBGPCIRADMontpellier SupAgroINRAIRDUniv MontpellierMontpellierFrance
- CIRADUMR PVBMTSaint‐PierreFrance
- CIRADUMR ASTREMontpellierFrance
- ASTREUniv MontpellierCIRADINRAMontpellierFrance
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16
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Chen B, Tong X, Zhang X, Gui W, Ai G, Huang L, Ding D, Zhang J, Kang L. Sulfation modification of dopamine in brain regulates aggregative behavior of animals. Natl Sci Rev 2021; 9:nwab163. [PMID: 35530433 PMCID: PMC9072122 DOI: 10.1093/nsr/nwab163] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2021] [Revised: 07/16/2021] [Accepted: 07/19/2021] [Indexed: 11/17/2022] Open
Abstract
Behavioral plasticity and the underlying neuronal plasticity represent a fundamental capacity of animals to cope with environmental stimuli. Behavioral plasticity is controlled by complex molecular networks that act under different layers of regulation. While various molecules have been found to be involved in the regulation of plastic behaviors across species, less is known about how organisms orchestrate the activity of these molecules as part of a coherent behavioral response to varying environments. Here we discover a mechanism for the regulation of animal behavioral plasticity involving molecular sulfation in the brain, a modification of substrate molecules by sulfotransferase (ST)-catalyzed addition of a sulfonate group (SO3) from an obligate donor, 3′-phosphoadenosine 5′-phosphosulfate (PAPS) to the substrates. We investigated aggregation behaviors of migratory locusts, which are well-known for extreme phase change plasticity triggered by population density. The processes of PAPS biosynthesis acted efficiently on induction of locust behavioral transition: Inhibition of PAPS synthesis solicited a behavioral shift from gregarious to solitarious states; external PAPS dosage, by contrast, promoted aggregation in solitarious locusts. Genetic or pharmacological intervention in the sulfation catalyzation resulted into pronounced solitarizing effects. Analysis of substrate-specific STs suggests a widespread involvement of sulfated neurotransmitters in the behavioral response. Dopamine in the brain was finally identified to be actively sulfate conjugated, and the sulfate conjugation enhanced the free DA-mediated behavioral aggregation. Similar results in Caenorhabditis elegans and mice indicate that sulfation may be involved more broadly in the modulation of animal aggregation. These findings reveal a general mechanism that effectively regulates animal social-like behavioral plasticity, possibly through sulfation-mediated modification of neural networks.
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Affiliation(s)
- Bing Chen
- School of Life Science, Institutes of Life Science and Green Development, Hebei University, Baoding 071002, China
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Xiwen Tong
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
- School of Life Sciences, South China Normal University, Guangzhou, 510631 China
| | - Xia Zhang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Wanying Gui
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Guoming Ai
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Lihua Huang
- School of Life Sciences, South China Normal University, Guangzhou, 510631 China
| | - Ding Ding
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Jiangxu Zhang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
| | - Le Kang
- School of Life Science, Institutes of Life Science and Green Development, Hebei University, Baoding 071002, China
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing 100101, China
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17
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Maeno KO, Piou C, Kearney MR, Ould Ely S, Ould Mohamed S, Jaavar MEH, Ould Babah Ebbe MA. A general model of the thermal constraints on the world's most destructive locust, Schistocerca gregaria. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2021; 31:e02310. [PMID: 33605475 DOI: 10.1002/eap.2310] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 09/10/2020] [Accepted: 11/13/2020] [Indexed: 06/12/2023]
Abstract
All terrestrial ectotherms are constrained to some degree by their thermal environment and the extent to which they can behaviorally buffer variable thermal conditions. New biophysical modeling methods (NicheMapR) allow the calculation of the body temperature of thermoregulating animals anywhere in the world from first principles, but require detailed observational data for parameterization and testing. Here we describe the thermoregulatory biology of marching bands of the desert locust, Schistocerca gregaria, in the Sahara Desert of Mauritania where extreme heat and strong diurnal fluctuations are a major constraint on activity and physiological processes. Using a thermal infrared camera in the field, we showed that gregarious nymphs altered the microhabitats they used, as well as postural thermoregulatory behaviors, to maintain relatively high body temperature (nearly 40°C). Field and laboratory experiments demonstrated that the preferred body temperature accelerated digestive rates. Migratory bands frequently left foraging sites with full guts before consuming all vegetation and moved to another habitat before emptying their foregut. Thus, the repertoire for behavioral thermoregulation in the desert locust strongly facilitates foraging and digestion rates, which may accelerate developmental rates and increase survival. We used our data to successfully parameterize a general biophysical model of thermoregulatory behavior that could capture hourly body temperature and activity at our remote site using globally available environmental forcing data. This modeling approach provides a stronger basis for forecasting thermal constraints on locust outbreaks under current and future climates.
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Affiliation(s)
- Koutaro Ould Maeno
- Livestock and Environment Division, Japan International Research Center for Agricultural Sciences (JIRCAS), Ohwashi 1-1, Tsukuba, Ibaraki, 305-8686, Japan
- The Mauritanian National Desert Locust Centre: Centre National de Lutte Antiacridienne (CNLA), Nouakchott, BP: 665, Mauritania
| | - Cyril Piou
- CIRAD, UMR CBGP, INRAE, Institut Agro, IRD, Université Montpellier, F-34398, Montpellier, France
| | - Michael R Kearney
- School of BioSciences, The University of Melbourne, Parkville, Victoria, 3052, Australia
| | - Sidi Ould Ely
- The Mauritanian National Desert Locust Centre: Centre National de Lutte Antiacridienne (CNLA), Nouakchott, BP: 665, Mauritania
- Direction of Agriculture, Ministry of Rural Development, Nouakchott, Mauritania
| | - Sid'Ahmed Ould Mohamed
- The Mauritanian National Desert Locust Centre: Centre National de Lutte Antiacridienne (CNLA), Nouakchott, BP: 665, Mauritania
| | - Mohamed El Hacen Jaavar
- The Mauritanian National Desert Locust Centre: Centre National de Lutte Antiacridienne (CNLA), Nouakchott, BP: 665, Mauritania
| | - Mohamed Abdallahi Ould Babah Ebbe
- The Mauritanian National Desert Locust Centre: Centre National de Lutte Antiacridienne (CNLA), Nouakchott, BP: 665, Mauritania
- Institut du Sahel (INSAH)/CILSS, BP 1530, Bamako, Mali
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18
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Knebel D, Sha-ked C, Agmon N, Ariel G, Ayali A. Collective motion as a distinct behavioral state of the individual. iScience 2021; 24:102299. [PMID: 33855280 PMCID: PMC8024921 DOI: 10.1016/j.isci.2021.102299] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2020] [Revised: 02/04/2021] [Accepted: 03/05/2021] [Indexed: 02/04/2023] Open
Abstract
The collective motion of swarms depends on adaptations at the individual level. We explored these and their effects on swarm formation and maintenance in locusts. The walking kinematics of individual insects were monitored under laboratory settings, before, as well as during collective motion in a group, and again after separation from the group. It was found that taking part in collective motion induced in the individual unique behavioral kinematics, suggesting the existence of a distinct behavioral mode that we term a "collective-motion-state." This state, characterized by behavioral adaptation to the social context, is long lasting, not induced by crowding per se, but only by experiencing collective motion. Utilizing computational models, we show that this adaptability increases the robustness of the swarm. Overall, our findings suggest that collective motion is not only an emergent property of the group but also depends on a behavioral mode, rooted in endogenous mechanisms of the individual.
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Affiliation(s)
- Daniel Knebel
- School of Zoology, Faculty of Life Sciences, Tel Aviv University, Tel Aviv, 6997801, Israel
- Department of Computer Science, Bar-Ilan University, Ramat-Gan, 5290002, Israel
| | - Ciona Sha-ked
- School of Zoology, Faculty of Life Sciences, Tel Aviv University, Tel Aviv, 6997801, Israel
| | - Noa Agmon
- Department of Computer Science, Bar-Ilan University, Ramat-Gan, 5290002, Israel
| | - Gil Ariel
- Department of Mathematics, Bar Ilan University, Ramat-Gan, 5290002, Israel
| | - Amir Ayali
- School of Zoology, Faculty of Life Sciences, Tel Aviv University, Tel Aviv, 6997801, Israel
- Sagol School of Neuroscience, Tel Aviv University, Tel Aviv, 6997801, Israel
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19
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One hundred years of phase polymorphism research in locusts. J Comp Physiol A Neuroethol Sens Neural Behav Physiol 2021; 207:321-326. [PMID: 33871680 PMCID: PMC8079285 DOI: 10.1007/s00359-021-01485-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2021] [Revised: 04/05/2021] [Accepted: 04/08/2021] [Indexed: 12/31/2022]
Abstract
One hundred years ago in 1921, Sir Boris Uvarov recognized that two locust species are one species but appearing in two different phases, a solitarious and a gregarious phase. As locust swarms are still a big problem affecting millions of people, basic research has tried to understand the causes for the transition between phases. This phenomenon of phase polymorphism, now called polyphenism, is a very complex multifactorial process and this short review will draw attention to this important aspect of insect research.
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20
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Vogt G. Epigenetic variation in animal populations: Sources, extent, phenotypic implications, and ecological and evolutionary relevance. J Biosci 2021. [DOI: 10.1007/s12038-021-00138-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
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21
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Tong X, Wang Y, Li J, Hu S, Yang P, Kang L. Transformation of glycerate kinase (GLYK) into Metarhizium acridum increases virulence to locust. PEST MANAGEMENT SCIENCE 2021; 77:1465-1475. [PMID: 33128436 DOI: 10.1002/ps.6165] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 10/01/2020] [Accepted: 10/31/2020] [Indexed: 06/11/2023]
Abstract
BACKGROUND Improvements in the virulence of the fungal pathogen Metarhizium acridum can crucially promote its efficacy to control locusts and grasshoppers. The polysaccharide components of the cell wall remarkably contribute to fungal virulence. RESULTS Here we found that M. acridum lacked the gene families of glycerate-3-kinase (GLYK) as the synthesis enzymes of saccharides. We then generated mutants by introducing the GLYK gene from the host-generalist M. robertsii into the host-specialist M. acridum. Consequently, compared with the wild-type strain, the mutant strain (Ma::MrGLYK) increased the level of phospho-6-fructose in mycelia, the length and density of the mannan fibril layer on the cell wall. The mutant strains increased the mannan fibril in the cell wall and resistance to heat stress. Further transcriptome analysis showed that compared with the wild-type strain, topical infection of Ma::MrGLYK strain induced higher expression of genes such as pattern-recognition proteins, serine protease, and CYP450s in locusts, while reduced the expression of antimicrobial peptide and phenoloxidase activity. Moreover, topical infection and injection of Ma::MrGLYK significantly increased the mortality and shortened the lifespan of locusts compared with wild-type M. acridum. CONCLUSION Our study highlighted the application potential of the novel genetically modified fungal mutant of the host-specialist M. acridum as a biocontrol agent against locust plagues. © 2020 Society of Chemical Industry.
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Affiliation(s)
- Xiwen Tong
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
| | - Yundan Wang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
| | - Juan Li
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
| | - Shuai Hu
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
| | - Pengcheng Yang
- Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing, China
| | - Le Kang
- State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China
- CAS Center for Excellence in Biotic Interactions, University of Chinese Academy of Sciences, Beijing, China
- Beijing Institutes of Life Science, Chinese Academy of Sciences, Beijing, China
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22
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Florent I, Chapuis MP, Labat A, Boisard J, Leménager N, Michel B, Desportes-Livage I. Integrative taxonomy confirms that Gregarina garnhami and G. acridiorum (Apicomplexa, Gregarinidae), parasites of Schistocerca gregaria and Locusta migratoria (Insecta, Orthoptera), are distinct species. ACTA ACUST UNITED AC 2021; 28:12. [PMID: 33620310 PMCID: PMC7901526 DOI: 10.1051/parasite/2021009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 02/02/2021] [Indexed: 11/27/2022]
Abstract
Orthoptera are infected by about 60 species of gregarines assigned to the genus Gregarina Dufour, 1828. Among these species, Gregarina garnhami Canning, 1956 from Schistocerca gregaria (Forsskål, 1775) was considered by Lipa et al. in 1996 to be synonymous with Gregarina acridiorum (Léger 1893), a parasite of several orthopteran species including Locusta migratoria (Linné, 1758). Here, a morphological study and molecular analyses of the SSU rDNA marker demonstrate that specimens of S. gregaria and specimens of L. migratoria are infected by two distinct Gregarina species, G. garnhami and G. acridiorum, respectively. Validation of the species confirms that molecular analyses provide useful taxonomical information. Phenotypic plasticity was clearly observed in the case of G. garnhami: the morphology of its trophozoites, gamonts and syzygies varied according to the geographical location of S. gregaria and the subspecies infected.
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Affiliation(s)
- Isabelle Florent
- Molécules de Communication et Adaptation des Microorganismes (MCAM, UMR 7245 CNRS), Département Adaptations du vivant (AVIV), Muséum National d'Histoire Naturelle, CNRS, CP 52, 57 rue Cuvier, 75231 Paris Cedex 05, France
| | - Marie Pierre Chapuis
- CBGP, Univ Montpellier, CIRAD, INRAE, Institut Agro, IRD, 34060 Montpellier, France - CIRAD, UMR CBGP, 34398 Montpellier, France
| | - Amandine Labat
- Molécules de Communication et Adaptation des Microorganismes (MCAM, UMR 7245 CNRS), Département Adaptations du vivant (AVIV), Muséum National d'Histoire Naturelle, CNRS, CP 52, 57 rue Cuvier, 75231 Paris Cedex 05, France
| | - Julie Boisard
- Molécules de Communication et Adaptation des Microorganismes (MCAM, UMR 7245 CNRS), Département Adaptations du vivant (AVIV), Muséum National d'Histoire Naturelle, CNRS, CP 52, 57 rue Cuvier, 75231 Paris Cedex 05, France - Structure et instabilité des génomes (STRING UMR 7196 CNRS/INSERM U1154), Département Adaptations du vivant (AVIV), Muséum National d'Histoire Naturelle, CNRS, INSERM, CP 26, 57 rue Cuvier, 75231 Paris Cedex 05, France
| | - Nicolas Leménager
- CBGP, Univ Montpellier, CIRAD, INRAE, Institut Agro, IRD, 34060 Montpellier, France - CIRAD, UMR CBGP, 34398 Montpellier, France
| | - Bruno Michel
- CBGP, Univ Montpellier, CIRAD, INRAE, Institut Agro, IRD, 34060 Montpellier, France - CIRAD, UMR CBGP, 34398 Montpellier, France
| | - Isabelle Desportes-Livage
- Molécules de Communication et Adaptation des Microorganismes (MCAM, UMR 7245 CNRS), Département Adaptations du vivant (AVIV), Muséum National d'Histoire Naturelle, CNRS, CP 52, 57 rue Cuvier, 75231 Paris Cedex 05, France
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23
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English S, Barreaux AMG. The evolution of sensitive periods in development: insights from insects. Curr Opin Behav Sci 2020. [DOI: 10.1016/j.cobeha.2020.07.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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24
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Lavy O, Gophna U, Gefen E, Ayali A. Locust Bacterial Symbionts: An Update. INSECTS 2020; 11:E655. [PMID: 32987763 PMCID: PMC7598710 DOI: 10.3390/insects11100655] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 09/22/2020] [Accepted: 09/23/2020] [Indexed: 12/12/2022]
Abstract
As one of the world's most infamous agricultural pests, locusts have been subjected to many in-depth studies. Their ability at one end of their behavioral spectrum to live as solitary individuals under specific conditions, and at the other end of the spectrum to form swarms of biblical scale, has placed them at the focus of vast research efforts. One important aspect of locust ecology is that of their interactions with the bacteria that reside in and on them. Although this aspect of locust ecology has been little studied relative to the mainstream locust research, these bacteria have been shown both to affect locust immunity and to participate in maintaining swarm integrity through the secretion of attractant volatiles. The interaction between locusts and their bacteria seems, however, to be bi-directional, with the bacteria themselves, as recently shown, being influenced by their host's swarming tendencies. This seems to be a consequence of the bacterial composition in the locust's gut, reproductive organs, and integument undergoing change with the change in their host's behavior. In this review we describe the current state of knowledge of the locust-bacteria interactions (data exists mainly for the desert and the migratory locusts), as well as highlighting some newly-gained understanding; and offer perspectives for future research.
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Affiliation(s)
- Omer Lavy
- School of Zoology, Tel Aviv University, Tel Aviv 6997801, Israel
| | - Uri Gophna
- School of Molecular Cell Biology and Biotechnology, Tel Aviv University, Tel Aviv 6997801, Israel;
| | - Eran Gefen
- Department of Biology, University of Haifa–Oranim, Kiryat Tivon 3600600, Israel;
| | - Amir Ayali
- School of Zoology, Tel Aviv University, Tel Aviv 6997801, Israel
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25
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Hanson F, Stanwyck E, Bohorquez A. The Effects of Population Density on the Incidence of Developmental Deformities in Chemosensory Organs of Tobacco Hornworm Larvae (Lepidoptera: Sphingidae). JOURNAL OF INSECT SCIENCE (ONLINE) 2020; 20:5. [PMID: 32677682 PMCID: PMC7366051 DOI: 10.1093/jisesa/ieaa062] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/14/2019] [Indexed: 06/11/2023]
Abstract
Cultures of Manduca sexta Johanssen in our laboratory were found to have larvae with missing or deformed mouthparts or antennae. Hypothesizing that these developmental deformities were caused by crowded rearing conditions, we reared larvae in four different population densities and recorded the incidence (% of larvae affected) and types of chemoreceptor deformities. Results showed that the incidence of these deformities was directly proportional to larval population density. Deformities of the maxilla and palp were the most frequent, followed by those of the antenna, epipharynx and maxillary styloconica. Life history traits of larval mass, food consumption, and rate of development were inversely related to larval density for both normal and deformed larvae. We discuss possible causes and mechanisms of these deformities and of changes to life history traits.
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Affiliation(s)
- Frank Hanson
- Department of Biological Sciences, University of Maryland, Baltimore County, Baltimore, MD
| | - Elizabeth Stanwyck
- Center for Interdisciplinary Research and Computing, University of Maryland, Baltimore County, Baltimore, MD
| | - Alexander Bohorquez
- Department of Biological Sciences, University of Maryland, Baltimore County, Baltimore, MD
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26
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Maeno KO, Piou C, Ghaout S. The desert locust, Schistocerca gregaria, plastically manipulates egg size by regulating both egg numbers and production rate according to population density. JOURNAL OF INSECT PHYSIOLOGY 2020; 122:104020. [PMID: 32035952 DOI: 10.1016/j.jinsphys.2020.104020] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 12/21/2019] [Accepted: 02/06/2020] [Indexed: 06/10/2023]
Abstract
Egg-size adjustment is one of the important plastic life-history traits for animals living in heterogeneous environments. The adaptive investment hypothesis predicts that mothers should increase progeny size according to certain cues predicting adverse future conditions of their offspring. However, reproductive resources are limited, and females have to simultaneously reduce egg number to allocate more resources to increase size. It remains unclear how single individuals alter egg size and number according to temporally heterogeneous environments. In the present study, we examined how desert locusts, Schistocerca gregaria, plastically alter egg size and number according to population density. We also investigated the trans-generational maternal effects on progeny characteristics as well as their own maternal physiological response (oviposition interval). Females kept in crowded conditions laid significantly larger and heavier eggs by reducing clutch size (number of eggs per egg pod) compared to isolated females, suggesting the existence of a reproductive trade-off between the two traits. The crowding-forced isolated females induced concerted changes not only in egg size but also in egg number tending towards those characteristics of gregarious control, implying that single individuals showed trade-off when egg size was increased. Double-blind testing confirmed the rapid crowding effects on egg size. Females also responded to crowding by extending the oviposition interval. As the oviposition interval extended, egg size increased, but clutch size decreased. Eggs from crowding-forced isolated females began to produce gregarious-phase type hatchlings (large and black) instead of solitarious-phase type ones (small and green). These results suggested that S. gregaria plastically manipulate egg size by regulating egg numbers and egg production rate, and indicated the presence of trans-generational maternal effects on progeny phase.
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Affiliation(s)
- Koutaro Ould Maeno
- Japan International Research Center for Agricultural Sciences (JIRCAS), Livestock and Environment Division, Ohwashi 1-1, Tsukuba, Ibaraki 305-8686, Japan; Laboratory of Insect Ecology, Graduate School of Agriculture Kyoto University Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606-8502, Japan.
| | - Cyril Piou
- CIRAD, UMR CBGP, F-34398 Montpellier, France; Centre National de Lutte Anti-acridienne (CNLAA), Aït-Melloul, BP 125, Inezgane, Agadir, Morocco; Ibn Zohr University, Agadir, Morocco
| | - Saïd Ghaout
- Centre National de Lutte Anti-acridienne (CNLAA), Aït-Melloul, BP 125, Inezgane, Agadir, Morocco
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27
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Dynamics of bacterial composition in the locust reproductive tract are affected by the density-dependent phase. FEMS Microbiol Ecol 2020; 96:5807075. [DOI: 10.1093/femsec/fiaa044] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 03/12/2020] [Indexed: 02/03/2023] Open
Abstract
ABSTRACTThe important role that locust gut bacteria play in their host biology is well accepted. Among other roles, gut bacteria are suggested to be involved in the locust swarming phenomenon. In addition, in many insect orders, the reproductive system is reported to serve as a vector for trans-generation bacterial inoculation. Knowledge of the bacterial composition of the locust reproductive tract is, however, practically absent. Here we characterized the reproductive system bacterial composition of gregarious and solitary females. We investigated its temporal dynamics and how it interacts with the locust phase, by comparative sampling and 16S rRNA amplicon sequencing. We revealed that the bacterial composition of the locust female reproductive tract is mostly constructed of three core genera: Micrococcus, Acinetobacter and Staphylococcus. While solitary females maintained a consistent bacterial composition, in the gregarious phase this consortium demonstrated large temporal shifts, mostly manifested by Brevibacterium blooms. These data are in accord with our previous report on the dynamics of locust hindgut bacterial microbiota, further indicating that locust endosymbionts are affected by their host population density. These newly understood dynamics may have implications beyond their contribution to our knowledge of locust ecology, as aggregation and mass migration are prevalent phenomena across many migrating animals.
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