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Journal of Insect Physiology Jan 2022At high density, juvenile locusts create marching hopper bands. Understanding the roles of temperature and vegetation on the movement of these bands shall allow to...
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.
Topics: Animals; Body Temperature Regulation; Feeding Behavior; Grasshoppers; Plants; Temperature
PubMed: 34826390
DOI: 10.1016/j.jinsphys.2021.104328 -
Biological Research Oct 2017This study aimed to reveal the mitochondrial genomes (mtgenomes) of Tetrix japonica and Alulatettix yunnanensis, and the phylogenetics of Orthoptera species.
OBJECTIVE
This study aimed to reveal the mitochondrial genomes (mtgenomes) of Tetrix japonica and Alulatettix yunnanensis, and the phylogenetics of Orthoptera species.
METHODS
The mtgenomes of A. yunnanensis and T. japonica were firstly sequenced and assembled through partial sequences amplification, and then the genome organization and gene arrangement were analyzed. Based on nucleotide/amino acid sequences of 13 protein-coding genes and whole mtgenomes, phylogenetic trees were established on 37 Orthoptera species and 5 outgroups, respectively.
RESULTS
Except for a regulation region (A+T rich region), a total of 37 genes were found in mtgenomes of T. japonica and A. yunnanensis, including 13 protein-coding genes, 2 ribosomal RNA genes, and 22 transfer RNA genes, which exhibited similar characters with other Orthoptera species. Phylogenetic tree based on 13 concatenated protein-coding nucleotide sequences were considered to be more suitable for phylogenetic reconstruction of Orthoptera species than amino acid sequences and mtgenomes. The phylogenetic relationships of Caelifera species were Acridoidea and Pamphagoidea > Pyrgomorphoidea > Pneumoroidea > Eumastacoidea > Tetrigoidea > Tridactyloidea. Besides, a sister-group relationship between Tettigonioidea and Rhaphidophoroidea was revealed in Ensifera.
CONCLUSION
Concatenated protein-coding nucleotide sequences of 13 genes were suitable for reconstruction of phylogenetic relationship in orthopteroid species. Tridactyloidea was a sister group of Tetrigoidea in Caelifera, and Rhaphidophoroidea was a sister group of Tettigonioidea in Ensifera.
Topics: Animals; Base Sequence; Evolution, Molecular; Genome, Mitochondrial; Grasshoppers; Phylogeny; Sequence Analysis, DNA
PubMed: 28982393
DOI: 10.1186/s40659-017-0132-9 -
Journal of Insect Science (Online) 2013This review focuses on grasshoppers that are polymorphic for Robertsonian translocations because in these organisms the clarity of meiotic figures allows the study of... (Review)
Review
This review focuses on grasshoppers that are polymorphic for Robertsonian translocations because in these organisms the clarity of meiotic figures allows the study of both chiasma distribution and the orientation of trivalents and multivalents in metaphase I. Only five species of such grasshoppers were found in the literature, and all of them were from the New World: Oedaleonotus enigma (Scudder) (Orthoptera: Acrididae), Leptysma argentina Bruner, Dichroplus pratensis Bruner, Sinipta dalmani Stål, and Cornops aquaticum Bruner. A general feature of these species (except O. enigma) is that fusion carriers suffer a marked reduction of proximal and interstitial (with respect to the centromere) chiasma frequency; this fact, along with the reduction in the number of linkage groups with the consequent loss of independent segregation, produces a marked decrease of recombination in fusion carriers. This reduction in recombination has led to the conclusion that Robertsonian polymorphic grasshopper species share some properties with inversion polymorphic species of Drosophila, such as the central-marginal pattern (marginal populations are monomorphic, central populations are highly polymorphic). This pattern might be present in D. pratensis, which is certainly the most complex Robertsonian polymorphism system in the present study. However, L. argentina and C. aquaticum do not display this pattern. This issue is open to further research. Since C. aquaticum is soon to be released in South Africa as a biological control, the latitudinal pattern found in South America may repeat there. This experiment's outcome is open and deserves to be followed.
Topics: Animals; Biological Evolution; Chromosomes, Insect; Grasshoppers; Hybridization, Genetic; Meiosis; Polymorphism, Genetic; Translocation, Genetic
PubMed: 23909914
DOI: 10.1673/031.013.4301 -
International Journal of Molecular... Jan 2022Tissue homeostasis is critical for maintaining organ shape, size, and function. The condition is regulated by the balance between the generation of new cells and the...
Tissue homeostasis is critical for maintaining organ shape, size, and function. The condition is regulated by the balance between the generation of new cells and the loss of senescent cells, and it involves many factors and mechanisms. The midgut, an important part of the intestinal tract, is responsible for digestion and nutrient absorption in insects. LmDDX47, the ortholog of DEAD-box helicase 47 from , is indispensable for sustaining a normal midgut in the nymphs. However, the underlying cellular and molecular mechanisms remain to be elucidated. In this study, knockdown resulted in atrophy of the midgut and gastric cecum in both nymph and adult locusts. After knockdown, the number of regenerative and columnar cells in the midgut was significantly reduced, and cell death was induced in columnar tissue. LmDDX47 was localized to the nucleolus; this was consistent with the reduction in 18S rRNA synthesis in the knockdown group. In addition, the acetylation and crotonylation levels of midgut proteins were significantly increased. Therefore, could be a key regulator of midgut homeostasis, regulating 18S rRNA synthesis as well as protein acetylation and crotonylation in the migratory locust.
Topics: Animals; DEAD-box RNA Helicases; Digestive System; Digestive System Physiological Phenomena; Female; Gene Expression Regulation; Homeostasis; Locusta migratoria; Male; RNA, Ribosomal, 18S
PubMed: 35054771
DOI: 10.3390/ijms23020586 -
Journal of Comparative Physiology. A,... May 2021One 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... (Review)
Review
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.
Topics: Animals; Behavior, Animal; Biogenic Amines; Biological Evolution; Biomedical Research; Female; Genotype; Grasshoppers; History, 20th Century; History, 21st Century; Male; Neurophysiology; Phenotype; Pheromones; Population Density; Sensory Thresholds; Social Behavior; Species Specificity
PubMed: 33871680
DOI: 10.1007/s00359-021-01485-3 -
Science Progress Oct 2021Grasshoppers and locusts are widely distributed worldwide, causing significant losses in agriculture. The origin and functions of their haemocytes are not entirely...
INTRODUCTION
Grasshoppers and locusts are widely distributed worldwide, causing significant losses in agriculture. The origin and functions of their haemocytes are not entirely understood.
OBJECTIVES
Insect haemocytes arbitrate cellular defence and participate in humoral defences. Due to their importance, the haemocytes of 35 species of grasshoppers and locusts from China were morphologically examined in this study. We aim to highlight a simple method for the morphological examination of insect haemocytes.
METHODS
The haemocytes were observed, counted and compared under a light microscope after Wright-Giemsa staining.
RESULTS
High complexity in form and shape were observed in the haemocytes. These include prohaemocytes, plasmatocytes, granulocytes, vermicytes, podocytes and megakaryocytes. No clear relationship was seen between the haemocyte type and their phylogenetic relationship among the three families examined. The high abundance of plasmatocytes and granulocytes suggests their importance in the immunity of grasshoppers and locusts. The minor haemocyte populations including prohaemocytes, vermicytes and podocytes may not be always present in individuals.
CONCLUSION
All examined species shared similarities in their haemocyte types. Wright-Giemsa staining is a simple and efficient method for evaluating haemocytes.
Topics: Animals; Granulocytes; Grasshoppers; Hemocytes; Humans; Phylogeny; Staining and Labeling
PubMed: 34751063
DOI: 10.1177/00368504211053551 -
Proceedings of the National Academy of... Jan 2020Gravity is one of the most ubiquitous environmental effects on living systems: Cellular and organismal responses to gravity are of central importance to understanding...
Gravity is one of the most ubiquitous environmental effects on living systems: Cellular and organismal responses to gravity are of central importance to understanding the physiological function of organisms, especially eukaryotes. Gravity has been demonstrated to have strong effects on the closed cardiovascular systems of terrestrial vertebrates, with rapidly responding neural reflexes ensuring proper blood flow despite changes in posture. Invertebrates possess open circulatory systems, which could provide fewer mechanisms to restrict gravity effects on blood flow, suggesting that these species also experience effects of gravity on blood pressure and distribution. However, whether gravity affects the open circulatory systems of invertebrates is unknown, partly due to technical measurement issues associated with small body size. Here we used X-ray imaging, radio-tracing of hemolymph, and micropressure measurements in the American grasshopper, , to assess responses to body orientation. Our results show that during changes in body orientation, gravity causes large changes in blood and air distribution, and that body position affects ventilation rate. Remarkably, we also found that insects show similar heart rate responses to body position as vertebrates, and contrasting with the classic understanding of open circulatory systems, have flexible valving systems between thorax and abdomen that can separate pressures. Gravitational effects on invertebrate cardiovascular and respiratory systems are likely to be widely distributed among invertebrates and to have broad influence on morphological and physiological evolution.
Topics: Adaptation, Physiological; Animals; Blood Pressure; Body Size; Cardiovascular Physiological Phenomena; Grasshoppers; Gravitation; Respiratory Physiological Phenomena
PubMed: 31932424
DOI: 10.1073/pnas.1915424117 -
Journal of Economic Entomology Jun 2023Timing of insecticide application can impact efficacy, given variation in both weather and development of the crop and its insect pests. Both target and nontarget...
Timing of insecticide application can impact efficacy, given variation in both weather and development of the crop and its insect pests. Both target and nontarget insects may vary in life stage and abundance at the time of application. In alfalfa Medicago sativa L. cropping systems, producers have interest in early-season insecticide applications to eliminate last-minute decisions about preharvest applications for alfalfa weevil Hypera postica (Gyllenhal) (Coleoptera: Curculionidae). The standard recommendation is based on scouting larvae close to the first harvest time. We compared early and standard timing of application of a lambda-cyhalothrin pyrethroid on alfalfa pest and beneficial insects. Field trials at a university research farm were conducted in 2020 and 2021. In 2020, early application was as effective as the standard timing against alfalfa weevil, as compared to the untreated control, but less effective than the standard timing in 2021. Effects of timing against Lygus bugs (Hemiptera: Miridae), grasshoppers (Orthoptera: Acrididae), and aphids (Hemiptera: Aphididae) were inconsistent between years. We observed the potential for early application to reduce negative impacts on ladybird beetles (Coleoptera: Coccinellidae) and spiders (Araneae), however, damsel bugs (Hemiptera: Nabidae) were similarly reduced by insecticide application regardless of timing. Overall arthropod community composition differed by both year and treatment. Future research should explore potential trade-offs of spray timing at larger spatial scales.
Topics: Animals; Insecticides; Medicago sativa; Insecta; Coleoptera; Weevils; Aphids; Heteroptera; Grasshoppers
PubMed: 37084333
DOI: 10.1093/jee/toad071 -
PeerJ 2023(Zheng, 1982) is a tiny grasshopper endemic to Qinling in China. For further study of its transcriptomic features, we obtained RNA-Seq data by Illumina HiSeq X Ten...
(Zheng, 1982) is a tiny grasshopper endemic to Qinling in China. For further study of its transcriptomic features, we obtained RNA-Seq data by Illumina HiSeq X Ten sequencing platform. Firstly, transcriptomic analysis showed that transcriptome read numbers of two female and one male samples were 25,043,314, 24,429,905, and 25,034,457, respectively. We assembled 65,977 unigenes, their average length was 1,072.09 bp, and the length of N50 was 2,031 bp. The average lengths of female and male unigenes were 911.30 bp, and 941.82 bp, and the N50 lengths were 1,745 bp and 1,735 bp, respectively. Eight databases were used to annotate the functions of unigenes, and 23,268 functional unigenes were obtained. Besides, we also studied the body color, immunity and insecticide resistance of Thirty-nine pigment-related genes were annotated. Some immunity genes and signaling pathways were found, such as JAK-STAT and Toll-LIKE receptor signaling pathways. There are also some insecticide resistance genes and signal pathways, like nAChR, GST and DDT. Further, some of these genes were differentially expressed in female and male samples, including pigment, immunity and insecticide resistance. The transcriptomic study of will provide data reference for gene prediction and molecular expression study of other Tetrigidae species in the future. Differential genetic screening of males and females provides a basis for studying sex and immune balance in insects.
Topics: Animals; Female; Male; Transcriptome; Grasshoppers; Gene Expression Profiling; High-Throughput Nucleotide Sequencing; RNA-Seq
PubMed: 37016680
DOI: 10.7717/peerj.15123 -
Current Biology : CB Apr 2006
Topics: Animals; Cannibalism; Food Preferences; Gryllidae; United States
PubMed: 16927460
DOI: 10.1016/j.cub.2006.03.033