Comparative bioactivity of selected extracts from Meliaceae and some commercial botanical insecticides against two noctuid caterpillars, Trichoplusia ni and Pseudaletia unipuncta

Abstract Food losses caused by insects during postharvest storage are of paramount economic importance worldwide, especially in Africa. Laboratory bioassays were conducted in stored grains to determine the toxicity of powders of Eugenia aromatica and Moringa oleifera alone or combined with enhanced diatomaceous earth (Probe-A® DE, 89.0% SiO2 and 5% silica aerogel) to adult Sitophilus granarius, Tribolium castaneum and Acanthoscelides obtectus. Adult mortality was observed up to 7 days, while progeny production was recorded at 6–10 weeks. LD50 and LT50 values for adult test insects exposed to plant powders and DE, showed that A. obtectus was the most susceptible towards the botanicals (LD50 0.179% and 0.088% wt/wt for E. aromatica and M. oleifera, respectively), followed by S. granarius. Tribolium castaneum was most tolerant (LD50 1.42% wt/wt and 1.40% wt/wt for E. aromatica and M. oleifera, respectively). The combined mixture of plant powders and DE controlled the beetles faster compared to the plant powders alone. LT50 ranged from 55.7 h to 62.5 h for T. castaneum exposed to 1.0% M. oleifera and 1.0% DE, and 0.5% E. aromatica and 1.0% DE, respectively. Botanicals caused significant reduction of F1 adults compared to the control. Combined action of botanical insecticides with DE as a grain protectant in an integrated pest management approach is discussed.

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Bacmid Expression of Granulovirus Enhancin En3 Accumulates in Cell Soluble Fraction to Potentiate Nucleopolyhedrovirus Infection

Viruses ◽

10.3390/v13071233 ◽

2021 ◽

Vol 13 (7) ◽

pp. 1233

Author(s):

Adriana Ricarte-Bermejo ◽

Oihane Simón ◽

Ana Beatriz Fernández ◽

Trevor Williams ◽

Primitivo Caballero

Keyword(s):

Trichoplusia Ni ◽

Recombinant Virus ◽

Spodoptera Exigua ◽

Insect Cells ◽

Soluble Fraction ◽

Autographa Californica ◽

Insect Midgut ◽

Baculovirus Infection ◽

Occlusion Bodies ◽

Infected Cells

Enhancins are metalloproteinases that facilitate baculovirus infection in the insect midgut. They are more prevalent in granuloviruses (GVs), constituting up to 5% of the proteins of viral occlusion bodies (OBs). In nucleopolyhedroviruses (NPVs), in contrast, they are present in the envelope of the occlusion-derived virions (ODV). In the present study, we constructed a recombinant Autographa californica NPV (AcMNPV) that expressed the Trichoplusia ni GV (TnGV) enhancin 3 (En3), with the aim of increasing the presence of enhancin in the OBs or ODVs. En3 was successfully produced but did not localize to the OBs or the ODVs and accumulated in the soluble fraction of infected cells. As a result, increased OB pathogenicity was observed when OBs were administered in mixtures with the soluble fraction of infected cells. The mixture of OBs and the soluble fraction of Sf9 cells infected with BacPhEn3 recombinant virus was ~3- and ~4.7-fold more pathogenic than BacPh control OBs in the second and fourth instars of Spodoptera exigua, respectively. In contrast, when purified, recombinant BacPhEn3 OBs were as pathogenic as control BacPh OBs. The expression of En3 in the soluble fraction of insect cells may find applications in the development of virus-based insecticides with increased efficacy.

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Efficacy of Petiveria Alliacea (Linneaus) leaf and root bark powder in the control of filariasis vector Culex Quinquefasciatus

The Journal of Basic and Applied Zoology ◽

10.1186/s41936-020-00199-3 ◽

2021 ◽

Vol 82 (1) ◽

Author(s):

Michael Olarewaju Akintan ◽

Joseph Onaolapo Akinneye ◽

Oluwatosin Betty Ilelakinwa

Keyword(s):

Synergistic Effect ◽

Culex Quinquefasciatus ◽

Mosquito Control ◽

Exposure Period ◽

Botanical Insecticides ◽

Adult Mosquito ◽

Root Bark ◽

Plant Powders ◽

Petiveria Alliacea ◽

Feeding Activities

Abstract Background Mosquitoes are vectors of parasitic diseases such as malaria, lymphatic filariasis, yellow fever, and dengue fever among others. They are well known as public enemies for their noise nuisance, biting annoyance, sleeplessness, allergic reactions, and diseases transmission during the biting and feeding activities. This then necessitate the search for insecticides of plant origin which are bio-degradable, non-toxic, and readily available for man use. Result This study, evaluated the fumigant efficacy of the powder of P. alliacea to control the adult stage of Culex mosquito. Powder of Petiveria alliacea were administered at different dose of (1 g, 2 g, 3 g, 4 g, and 5 g), respectively. Result obtained shows the fumigant effect of the powder were effective with percentage mortality of 18.33–60.00% for the leaf powder and 23.30–71.60% for the root powder within 2 h post-treatment period (P < 0.05). The synergistic effect of the leaf and root powder was also investigated. The lethal dosage (LD50) of the leaf, root, and synergistic effect of leaf and root bark powder required to kill 50% of the adult Culex quinquefasciatus was 3.76 g, 2.86 g, and 2.63 g, respectively. However, 25.06 g, 15.25 g, and 12.94 g of the leaf, root, and leaf and root powder were required to kill 90% (LD90) after a 2-h exposure period. Conclusion These finding suggested P. alliacea powder could be a good source of insecticide which may be used for the production of biopesticides. The present findings have important implications in the practical control of adult mosquito by using botanical insecticides. These plant powders are easy to prepare, inexpensive, and safe for use in mosquito control.

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Efficacy of Botanical Insecticides against the Pea Aphid, Acyrthosiphon pisum (Harris) and Effect on Some of Its Natural Enemies on Field Pea in South Central Ethiopia

Science Technology and Arts Research Journal ◽

10.4314/star.v4i2.7 ◽

2016 ◽

Vol 4 (2) ◽

pp. 53 ◽

Cited By ~ 1

Author(s):

Lemmessa Gemmeda ◽

Gashawbeza Ayalew

Keyword(s):

Natural Enemies ◽

Acyrthosiphon Pisum ◽

Field Pea ◽

Pea Aphid ◽

Botanical Insecticides ◽

Central Ethiopia ◽

South Central

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The unusual structure of the PiggyMac cysteine-rich domain reveals zinc finger diversity in PiggyBac-related transposases

Mobile DNA ◽

10.1186/s13100-021-00240-4 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Marc Guérineau ◽

Luiza Bessa ◽

Séverine Moriau ◽

Ewen Lescop ◽

François Bontems ◽

...

Keyword(s):

Zinc Finger ◽

Dna Cleavage ◽

Trichoplusia Ni ◽

Catalytic Domain ◽

Structural Diversity ◽

Paramecium Tetraurelia ◽

Lysine Methylation ◽

Unusual Structure ◽

Rich Domain ◽

Cysteine Rich Domain

Abstract Background Transposons are mobile genetic elements that colonize genomes and drive their plasticity in all organisms. DNA transposon-encoded transposases bind to the ends of their cognate transposons and catalyze their movement. In some cases, exaptation of transposon genes has allowed novel cellular functions to emerge. The PiggyMac (Pgm) endonuclease of the ciliate Paramecium tetraurelia is a domesticated transposase from the PiggyBac family. It carries a core catalytic domain typical of PiggyBac-related transposases and a short cysteine-rich domain (CRD), flanked by N- and C-terminal extensions. During sexual processes Pgm catalyzes programmed genome rearrangements (PGR) that eliminate ~ 30% of germline DNA from the somatic genome at each generation. How Pgm recognizes its DNA cleavage sites in chromatin is unclear and the structure-function relationships of its different domains have remained elusive. Results We provide insight into Pgm structure by determining the fold adopted by its CRD, an essential domain required for PGR. Using Nuclear Magnetic Resonance, we show that the Pgm CRD binds two Zn2+ ions and forms an unusual binuclear cross-brace zinc finger, with a circularly permutated treble-clef fold flanked by two flexible arms. The Pgm CRD structure clearly differs from that of several other PiggyBac-related transposases, among which is the well-studied PB transposase from Trichoplusia ni. Instead, the arrangement of cysteines and histidines in the primary sequence of the Pgm CRD resembles that of active transposases from piggyBac-like elements found in other species and of human PiggyBac-derived domesticated transposases. We show that, unlike the PB CRD, the Pgm CRD does not bind DNA. Instead, it interacts weakly with the N-terminus of histone H3, whatever its lysine methylation state. Conclusions The present study points to the structural diversity of the CRD among transposases from the PiggyBac family and their domesticated derivatives, and highlights the diverse interactions this domain may establish with chromatin, from sequence-specific DNA binding to contacts with histone tails. Our data suggest that the Pgm CRD fold, whose unusual arrangement of cysteines and histidines is found in all PiggyBac-related domesticated transposases from Paramecium and Tetrahymena, was already present in the ancestral active transposase that gave rise to ciliate domesticated proteins.

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Expression of biologically active human butyrylcholinesterase in the cabbage looper (Trichoplusia ni)

Biotechnology and Applied Biochemistry ◽

10.1042/ba19990038 ◽

2000 ◽

Vol 31 (3) ◽

pp. 225 ◽

Cited By ~ 6

Author(s):

Peter L. Platteborze ◽

Clarence A. Broomfield

Keyword(s):

Trichoplusia Ni ◽

Biologically Active ◽

Cabbage Looper ◽

Human Butyrylcholinesterase

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Bacillus thuringiensis Bel Protein Enhances the Toxicity of Cry1Ac Protein to Helicoverpa armigera Larvae by Degrading Insect Intestinal Mucin

Applied and Environmental Microbiology ◽

10.1128/aem.00532-09 ◽

2009 ◽

Vol 75 (16) ◽

pp. 5237-5243 ◽

Cited By ~ 47

Author(s):

Shangling Fang ◽

Li Wang ◽

Wei Guo ◽

Xia Zhang ◽

Donghai Peng ◽

...

Keyword(s):

Bacillus Thuringiensis ◽

Helicoverpa Armigera ◽

Trichoplusia Ni ◽

Knockout Mutant ◽

Gene Encoding ◽

In Vitro Degradation ◽

Intestinal Mucin ◽

Helicoverpa Armígera ◽

Cry1ac Protein

ABSTRACT Bacillus thuringiensis has been used as a bioinsecticide to control agricultural insects. Bacillus cereus group genomes were found to have a Bacillus enhancin-like (bel) gene, encoding a peptide with 20 to 30% identity to viral enhancin protein, which can enhance viral infection by degradation of the peritrophic matrix (PM) of the insect midgut. In this study, the bel gene was found to have an activity similar to that of the viral enhancin gene. A bel knockout mutant was constructed by using a plasmid-free B. thuringiensis derivative, BMB171. The 50% lethal concentrations of this mutant plus the cry1Ac insecticidal protein gene were about 5.8-fold higher than those of the BMB171 strain. When purified Bel was mixed with the Cry1Ac protein and fed to Helicoverpa armigera larvae, 3 μg/ml Cry1Ac alone induced 34.2% mortality. Meanwhile, the mortality rate rose to 74.4% when the same amount of Cry1Ac was mixed with 0.8 μg/ml of Bel. Microscopic observation showed a significant disruption detected on the midgut PM of H. armigera larvae after they were fed Bel. In vitro degradation assays showed that Bel digested the intestinal mucin (IIM) of Trichoplusia ni and H. armigera larvae to various degrading products, similar to findings for viral enhancin. These results imply Bel toxicity enhancement depends on the destruction of midgut PM and IIM, similar to the case with viral enhancin. This discovery showed that Bel has the potential to enhance insecticidal activity of B. thuringiensis-based biopesticides and transgenic crops.

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