Migratory Grasshopper Melanoplus Sanguinipes Research Articles

Efficacy of Two Entomopathogenic Fungi, Metarhizium brunneum, Strain F52 Alone and Combined with Paranosema locustae against the Migratory Grasshopper, Melanoplus sanguinipes, under Laboratory and Greenhouse Conditions.

Grasshopper outbreaks cause significant damage to crops and grasslands in US. Chemical control is widely used to suppress these pests but it reduces environmental quality. Biological control of insect pests is an alternative way to reduce the use of chemical insecticides. In this context, two entomopathogenic fungi, Metarhizium brunneum strain F52 and Paranosema locustae were evaluated as control agents for the pest migratory grasshopper Melanoplus sanguinipes under laboratory and greenhouse conditions. Third-instar grasshoppers, reared in the laboratory, were exposed up to fourteen days to wheat bran treated with different concentrations of each of the fungi alone or the two pathogens combined. In the greenhouse, nymphs were placed individually in cages where they were able to increase their body temperatures by basking in the sun in an attempt to inhibit the fungal infection, and treated with each pathogen alone or in combination. Mortality was recorded daily and presence of fungal outgrowth in cadavers was confirmed by recording fungal mycosis for two weeks’ post-treatment (PT). For combination treatment, the nature of the pathogen interaction (synergistic, additive, or antagonistic effects) was also determined. In laboratory conditions, all treatments except P. locustae alone resulted in grasshopper mortality. The application of the pathogen combinations caused 75% and 77%, mortality for lower and higher concentrations, respectively than each of the pathogens alone. We infer a synergistic effect occurred between the two agents. In greenhouse conditions, the highest mortalities were recorded in combination fungal treatments with a M. brunneum dose (60% mortality) and with a combination of the two pathogens in which M. brunneum was applied at high rate (50%) two weeks after application. This latter combination also exhibited a synergistic effect. Exposure to the P. locustae treatment did not lead to mortality until day 14 PT. We infer that these pathogens are promising for developing a biopesticide formulation for rangeland pest grasshopper management.

Combining RNA-seq and proteomic profiling to identify seminal fluid proteins in the migratory grasshopper Melanoplus sanguinipes (F).

BackgroundSeminal fluid proteins control many aspects of fertilization and in turn, they play a key role in post-mating sexual selection and possibly reproductive isolation. Because effective proteome profiling relies on the availability of high-quality DNA reference databases, our knowledge of these proteins is still largely limited to model organisms with ample genetic resources. New advances in sequencing technology allow for the rapid characterization of transcriptomes at low cost. By combining high throughput RNA-seq and shotgun proteomic profiling, we have characterized the seminal fluid proteins secreted by the primary male accessory gland of the migratory grasshopper (Melanoplus sanguinipes), one of the main agricultural pests in central North America.ResultsUsing RNA sequencing, we characterized the transcripts of ~ 8,100 genes expressed in the long hyaline tubules (LHT) of the accessory glands. Proteomic profiling identified 353 proteins expressed in the long hyaline tubules (LHT). Of special interest are seminal fluid proteins (SFPs), such as EJAC-SP, ACE and prostaglandin synthetases, which are known to regulate female oviposition in insects.ConclusionsOur study provides new insights into the proteomic components of male ejaculate in Orthopterans, and highlights several important patterns. First, the presence of proteins that lack predicted classical secretory tags in accessory gland proteomes is common in male accessory glands. Second, the products of a few highly expressed genes dominate the accessory gland secretions. Third, accessory gland transcriptomes are enriched for novel transcripts. Fourth, there is conservation of SFPs’ functional classes across distantly related taxonomic groups with very different life histories, mating systems and sperm transferring mechanisms. The identified SFPs may serve as targets of future efforts to develop species- specific genetic control strategies.Electronic supplementary materialThe online version of this article (doi:10.1186/s12864-015-2327-1) contains supplementary material, which is available to authorized users.

Increased juvenile hormone levels after long-duration flight in the grasshopper, Melanoplus sanguinipes

Although, in many insects, migration imposes a cost in terms of timing or amount of reproduction, in the migratory grasshopper Melanoplus sanguinipes performance of long-duration flight to voluntary cessation or exhaustion accelerates the onset of first reproduction and enhances reproductive success over the entire lifetime of the insect. Since juvenile hormone (JH) is involved in the control of reproduction in most species, we examined JH titer after long flight using a chiral selective radioimmunoassay. JH levels increased on days 5 and 8 in animals flown to exhaustion on day 4 but not in 1-h or non-flier controls. No difference was seen in the diel pattern of JH titer, but hemolymph samples were taken between 5 and 7 h after lights on. Treatment of grasshoppers with JH-III mimicked the effect of long-duration flight in the induction of early reproduction. The increased JH titer induced by performance of long-duration flight is thus at least one component of flight-enhanced reproduction. To test the possibility that post-flight JH titer increases are caused by adipokinetic hormone (AKH) released during long flights, a series of injections of physiological doses of Lom-AKH I were given to unflown animals to simulate AKH release during long flight. This treatment had no effect on JH titers. Thus, although AKH is released during flight and controls lipid mobilization, it is not the factor responsible for increased JH titers after long-duration flight.

Heritability and physiological correlates of migratory tendency in the grasshopper Melanoplus sanguinipes

Abstract. Durations of tethered flights by the North American migratory grasshopper Melanoplus sanguinipes Fabricius are bimodally distributed: most individuals either will not fly, or else will fly for many hours. This observation suggests a simple measure (the ‘one‐hour rule’) for distinguishing migrants from non‐migrants. This measure is repeatable (repeatability = 0.6–0.7). Using laboratory‐reared offspring of grasshoppers from an Arizona population of mixed migratory tendency, a breeding experiment was conducted to determine the heritability of migratory tendency and possible correlated responses to selection on migratory behaviour. When migratory tendency is considered as a threshold trait, the heritability of liability is in the range 0.5–0.6. Most families in the breeding experiment had at least some migrants among their offspring; selection on migratory incidence had a correlated effect on the durations of flights by these individuals. The magnitude of thoracic lipid reserves showed a modest correlated response to selection on migratory behaviour. Thoracic and abdominal lipid reserves in identified migrants are reduced by flight, indicating that lipid is mobilized and consumed during flight in this species.

The genome of Melanoplus sanguinipes entomopoxvirus.

The family Poxviridae contains two subfamilies: the Entomopoxvirinae (poxviruses of insects) and the Chordopoxvirinae (poxviruses of vertebrates). Here we present the first characterization of the genome of an entomopoxvirus (EPV) which infects the North American migratory grasshopper Melanoplus sanguinipes and other important orthopteran pests. The 236-kbp M. sanguinipes EPV (MsEPV) genome consists of a central coding region bounded by 7-kbp inverted terminal repeats and contains 267 open reading frames (ORFs), of which 107 exhibit similarity to previously described genes. The presence of genes not previously described in poxviruses, and in some cases in any other known virus, suggests significant viral adaptation to the arthropod host and the external environment. Genes predicting interactions with host cellular mechanisms include homologues of the inhibitor of apoptosis protein, stress response protein phosphatase 2C, extracellular matrixin metalloproteases, ubiquitin, calcium binding EF-hand protein, glycosyltransferase, and a triacylglyceride lipase. MsEPV genes with putative functions in prevention and repair of DNA damage include a complete base excision repair pathway (uracil DNA glycosylase, AP endonuclease, DNA polymerase beta, and an NAD+-dependent DNA ligase), a photoreactivation repair pathway (cyclobutane pyrimidine dimer photolyase), a LINE-type reverse transcriptase, and a mutT homologue. The presence of these specific repair pathways may represent viral adaptation for repair of environmentally induced DNA damage. The absence of previously described poxvirus enzymes involved in nucleotide metabolism and the presence of a novel thymidylate synthase homologue suggest that MsEPV is heavily reliant on host cell nucleotide pools and the de novo nucleotide biosynthesis pathway. MsEPV and lepidopteran genus B EPVs lack genome colinearity and exhibit a low level of amino acid identity among homologous genes (20 to 59%), perhaps reflecting a significant evolutionary distance between lepidopteran and orthopteran viruses. Divergence between MsEPV and the Chordopoxvirinae is indicated by the presence of only 49 identifiable chordopoxvirus homologues, low-level amino acid identity among these genes (20 to 48%), and the presence in MsEPV of 43 novel ORFs in five gene families. Genes common to both poxvirus subfamilies, which include those encoding enzymes involved in RNA transcription and modification, DNA replication, protein processing, virion assembly, and virion structural proteins, define the genetic core of the Poxviridae.

Mobilization of lipid and carbohydrate reserves in the migratory grasshopper Melanoplus sanguinipes

Abstract. The North American migratory grasshopper Melanoplus sanguinipes Fabricius (Orthoptera: Acrididae) exhibits heritable variation in predisposition to make long‐duration flights, and performance of long‐duration flight enhances reproductive output. As a first step in understanding the physiological basis of these phenomena, we examined the mobilization of lipid and carbohydrate reserves during flight and in response to injection of extracts of the corpora cardiaca. Extract of conspecific corpora cardiaca elevates the concentration of haemolymph lipid. Both synthetic locust adipokinetic hormone I (AKH I) and synthetic Locusta migratoria AKH II raise the concentration of lipid in the haemolymph. However, although AKH I is more active than AKH II in locusts, dose‐response curves for the two peptides are similar in M.sanguinipes. Neither extract of conspecific corpora cardiaca nor locust AKH I affects haemolymph carbohydrate in this species. Haemolymph carbohydrate and total glycogen reserves are Diminished by tethered flight; in contrast, haemolymph lipid is elevated by flight. Grasshoppers identified as presumptive migrants or non‐migrants do not differ significantly in body composition. Total lipid reserves did not decrease measurably after extended flight, even though total reserves of carbohydrate do not appear to be sufficient to maintain the durations of flight performed.

Laboratory Residual Activity Of Spinosad On The Migratory Grasshopper, 1994

Abstract The activity of spinosad, the first of the naturalyte control class, was evaluated against the migratory grasshopper Melanoplus sanguinipes by treating wheat seedlings with DeVilbis sprays of liquids or 0.3 gms. of bran bait per replicate on the surface of the pot. The bran baits were formulated utilizing technical materials deliveredin acetone and mixed throughout with commercial bran flakes. For this test, 3 replicates of 5, 2nd instar grasshoppers were used per rate and 6 rates were evaluated. Chlorpyrifo was used as the standard either as a Lorsban 4E spray or as a chlorpyrifos bran mixture. The number of dead nymphs was recorded at 24, 48, 72, and 108 hours.

Reduction of grasshopper populations following field application of the fungusBeauveria bassiana

Conidia of the Hyphomycete fungus Beauveria bassiana (Bals.) were applied in an attempt to reduce field populations of grasshoppers, primarily the migratory grasshopper Melanoplus sanguinipes (Fabricius). Dry spores were applied with wheat bran carrier to three fallow fields at a rate of 2.0 × 1013 spores ha−1 in 10 kg bait ha−1. Examination of culture plates that had been placed in the field to capture spores and of bran carrier with scanning electron microscopy indicated that a substantial portion of the B. bassiana colony—forming units (spores and clumps of spores) did not adhere to the bran and were applied in the field as free particles. Grasshoppers collected from the treated plots at intervals after application were assayed for infection by B. bassiana. The observed rate of mycosis in the treated populations was 70% of those collected after 2 days, declining to 41% by 13 days and 5% by 19 days after application. Analysis of reductions in population density gave results in agreement with the infecti...

HYBRIDIZATION STUDIES IN THE MIGRATORY GRASSHOPPER MELANOPLUS SANGUINIPES (F.) (ACRIDIDAE)

AbstractThree subspecies of the migratory grasshopper Melanoplus sanguinipes (F.) are recognized by Gurney and Brooks (1959) who, on the basis of morphology and presence of intergrades in collections, do not consider the taxa sufficiently different to warrant according them species status. Present experiments show that members of distant populations, when crossed, readily produce viable and fertile hybrids of both sexes. It is, however, premature to claim that the groups are conspecific without confirmatory information on, for instance, genetic distances and mating discrimination indices. Nonetheless, it is hypothesized that these parameters are expected to have low values given the hybridization results.

THE LIFE CYCLE AND ULTRASTRUCTURE OF MALAMEBA LOCUSTAE (KING AND TAYLOR) (AMOEBIDAE) IN THE MIGRATORY GRASSHOPPER MELANOPLUS SANGUINIPES (F.) (ACRIDIDAE),

AbstractThe life history and ultrastructure of the protozoan Malameba locustae (King and Taylor) were studied in the migratory grasshopper Melanoplus sanguinipes (F.) using feeding and injection studies. Insects fed cysts developed infection in the Malpighian tubules 5–6 days later; no trophozoites were observed in haemolymph samples taken 2–20 days post-feeding. After excystment, a few trophozoites entered the midgut epithelium and many were located near the basement membrane of the epithelial cells, where they appeared to degenerate. Trophozoites were not seen to divide in the midgut epithelium, and apparently did not damage this tissue. Trophozoites injected directly into the haemocoel could not be recovered even 4 h after injection, and the Malpighian tubules did not become infected. It was concluded that trophozoites did not penetrate the midgut to enter the haemocoel or move through the haemocoel to infect the Malpighian tubules, but instead probably entered the tubules directly from the gut. Trophozoite ultrastructure in midgut and Malpighian tubules, and cyst wall deposition were described.

Mode of action of the sesquiterpene lactone, tenulin, from Helenium amarum against herbivorous insects.

Tenulin [1], a sesquiterpene lactone from Helenuim amarum, is a potent antifeedant to the European corn borer Ostrinia nubilalis. At 3 mumol/g in artificial diets, 1 reduced growth and delayed larval development of O. nubilalis and the variegated cutworm Peridroma saucia larvae. An especially pronouned carry-over effect in O. nubilis was substantial reduction in fecundity of adult moths resulting from treated larvae. The LD50 (lethal dose for 50% mortality) of 1 by injection in the migratory grasshopper Melanoplus sanguinipes was 0.88 mumol/insect. Toxicity in M. sanguinipes was antagonized by co-administration of cysteine, suggesting that the cyclopentenone group of tenulin undergoes Michael addition of biological nucleophiles in vivo. This mechanism was partially confirmed by the finding that only tenulin analogues capable of acting as electrophic acceptors had significant antifeedant activity.

Metabolites of insecticidal chromenes from the migratory grasshopper Melanoplus sanguinipes

Three insecticidal acetylchromenes, including encecalin, and precocene II were topically administered to adults of the migratory grasshopper Melanoplus sanguinipes. Metabolites formed and excreted via the frass were identified by gas chromatography-mass spectrometry (GC-MS) and by direct comparison with reference compounds obtained by partial synthesis or from plant sources. Of the 12 metabolites found, six compounds were new natural products. Their tentative structure elucidation is described based on MS analysis. The biological importance of the elucidated chromene metabolism in M. sanguinipes is discussed for the excretion and detoxification of potentially hazardous compounds.

Empirical Model of Nymphal Development for the Migratory Grasshopper, Melanoplus sanguinipes (Orthoptera: Acrididae) 1

A new function was empirically derived to describe nymphal development of the migratory grasshopper Melanoplus sanguinipes (F.). This nonlinear equation was to fit to a large data set from the literature and compared with two previously proposed nonlinear models and the commonly used degree-day linear model. The functions were also compared in their ability to predict development under conditions of alternating temperatures, including temperatures that would often occur in the field. Although all models fit the data well at intermediate temperatures, the new model was shown to be preferable to the other models in the high- and low-temperature range.

INHERITANCE OF REDUCED-EYE IN THE GRASSHOPPER MELANOPLUS SANGUINIPES

The inheritance of an eye abnormality, reduced-eye, is described in the migratory grasshopper Melanoplus sanguinipes (Fabricius). Phenotypically, the compound eyes are flat and narrow and greatly reduced in size. Facets are absent. Pleiotropic effects include a crease in the vertex of the head, the absence of ocelli and low viability. Data from crosses suggest that reduced-eye is monogenically controlled and is due to an autosomal recessive.

Development of Diplotriaena tricuspis (Nematoda:Diplotriaenoidea), a parasite of Corvidae, in intermediate and definitive hosts

Development of Diplotriaena tricuspis (Fedtschenko, 1874) Henry and Ozoux, 1909, of the American crow Corvus brachyrhynchos Brehm, occurred in capsules in the fat body of the migratory grasshopper Melanoplus sanguinipes F. and the African desert locust Schistocerca gregaria L. At 30 °C the first moult began at 4 days and the second at 8 days after infection in late-instar nymphal and young adult insects. One unusual feature was the rapid growth of the oesophagus which compressed the intestine of the third-stage larva. Grasshoppers appeared to be more suitable intermediate hosts than locusts. In crows, larvae of D. tricuspis apparently underwent their early development in the hepatic portal system and moved via the posterior vena cava to the heart. The third moult began at 4 days and the fourth at 20 days after infection. Subadult nematodes were in the right heart 25 days after infection. Nematodes broke out of arteries within the lungs and moved to the air sacs as early as 30 days after infection. The prepatent period was approximately 4 months. Attempts to transmit D. tricuspis to various noncorvids were unsuccessful.