scholarly journals Spatial distribution and sample size to estimate Lycosa erythrognatha (Araneae: Lycosidae) population density overwintering

2020 ◽  
Author(s):  
E. Engel ◽  
M. P. B. Pasini ◽  
N. A. Kist
Keyword(s):  
Biological Control ◽  
Spatial Distribution ◽  
Population Density ◽  
Environmental Quality ◽  
Host Plants ◽  
Insect Pest ◽  
Conservation Biological Control ◽  
Gregarious Behavior ◽  
Minimum Number

Abstract Lycosa erythrognatha Lucas, 1833 (Araneae: Lycosidae) is a predatory arthropod with potential for conservation biological control. In addition to being considered a bioindicator of environmental quality, this arthropod provides an important service for agriculture by reducing insect-pest populations. In this work we seek to understand how the plants Andropogon bicornis L., Saccharum angustifolium Nees and Eustachys retusa Lag (Poales: Poaceae) and their different clump sizes affect the population density, spatial distribution and determination of the minimum number of samples to estimate its population density during the winter. Among the evaluated host plants, S. angustifolium and A. bicornis presented higher population density than E. retusa, but we observed that the clump diameter significantly influences the population density and the minimum number of samples. We observed a gregarious behavior in plants of A. bicornis and E. retusa. For S. angustifolium, a uniform distribution was observed.

scholarly journals How Effective Is Conservation Biological Control in Regulating Insect Pest Populations in Organic Crop Production Systems?

Insects ◽  
2020 ◽  
Vol 11 (11) ◽  
pp. 744
Author(s):  
Raymond A. Cloyd
Keyword(s):  
Biological Control ◽  
Natural Enemies ◽  
Crop Production ◽  
Scientific Literature ◽  
Production Systems ◽  
Insect Pest ◽  
Conservation Biological Control ◽  
Flowering Plants ◽  
Floral Resources ◽  
Organic Crop Production

Organic crop production systems are designed to enhance or preserve the presence of natural enemies, including parasitoids and predators, by means of conservation biological control, which involves providing environments and habitats that sustain natural enemy assemblages. Conservation biological control can be accomplished by providing flowering plants (floral resources) that will attract and retain natural enemies. Natural enemies, in turn, will regulate existing insect pest populations to levels that minimize plant damage. However, evidence is not consistent, based on the scientific literature, that providing natural enemies with flowering plants will result in an abundance of natural enemies sufficient to regulate insect pest populations below economically damaging levels. The reason that conservation biological control has not been found to sufficiently regulate insect pest populations in organic crop production systems across the scientific literature is associated with complex interactions related to intraguild predation, the emission of plant volatiles, weed diversity, and climate and ecosystem resources across locations where studies have been conducted.

Yellow Brazilian Pepper-tree Leaf Galler (suggested common name) Calophya latiforceps Burckhardt (Insecta: Hemiptera: Calophyidae: Calophyinae)

EDIS ◽  
2017 ◽  
Vol 2017 (6) ◽  
Author(s):  
James P. Cuda ◽  
Patricia Prade ◽  
Carey R. Minteer-Killian
Keyword(s):  
Biological Control ◽  
North America ◽  
Natural Enemies ◽  
Host Plants ◽  
Classical Biological Control ◽  
Biological Control Agents ◽  
Pepper Tree ◽  
Brazilian Pepper ◽  
Close Relatives ◽  
Tree Leaf

In the late 1970s, Brazilian peppertree, Schinus terebinthifolia Raddi (Sapindales: Anacardiaceae), was targeted for classical biological control in Florida because its invasive properties (see Host Plants) are consistent with escape from natural enemies (Williams 1954), and there are no native Schinus spp. in North America. The lack of native close relatives should minimize the risk of damage to non-target plants from introduced biological control agents (Pemberton 2000). [...]

Determination of the minimum number of technological bases of a part

2020 ◽  
pp. 73-75
Author(s):  
B.M. Bazrov ◽  
T.M. Gaynutdinov
Keyword(s):  
Cost Price ◽  
Labor Input ◽  
Part Surface ◽  
Technological Base ◽  
Size Accuracy ◽  
Minimum Number ◽  
The Cost ◽  
Input Cost ◽  
Selection Of

The selection of technological bases is considered before the choice of the type of billet and the development of the route of the technological process. A technique is proposed for selecting the minimum number of sets of technological bases according to the criterion of equality in the cost price of manufacturing the part according to the principle of unity and combination of bases at this stage. Keywords: part, surface, coordinating size, accuracy, design and technological base, labor input, cost price. [email protected]

scholarly journals Investigating the Parasitoid Community Associated with the Invasive Mealybug Phenacoccus solenopsis in Southern China

Insects ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 290
Author(s):  
Hua-Yan Chen ◽  
Hong-Liang Li ◽  
Hong Pang ◽  
Chao-Dong Zhu ◽  
Yan-Zhou Zhang
Keyword(s):  
Biological Control ◽  
Species Delimitation ◽  
Southern China ◽  
Insect Pest ◽  
Integrated Approach ◽  
Molecular Data ◽  
Coi Gene ◽  
Morphological Examination ◽  
Accurate Identification ◽  
Phenacoccus Solenopsis

The cotton mealybug Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae), is an emerging invasive insect pest in China. Hymenopteran parasitoids are the key organisms for suppressing populations of P. solenopsis in the field, and therefore could be used as biological agents. Accurate identification of the associated parasitoids is the critical step to assess their potential role in biological control. In this study, we facilitated the identification of the parasitoid composition of P. solenopsis using an integrated approach of species delimitation, combining morphology with molecular data. Eighteen Hymenoptera parasitoid species belonging to 11 genera of four families are recognized based on morphological examination and molecular species delimitation of the mitochondrial cytochrome c oxidase 1 (COI) gene and the 28S rDNA using the automatic barcode gap discovery (ABGD) and the Bayesian Poisson tree processes model (bPTP). Among these species, eight species are primary parasitoids with Aenasius arizonensis (Girault) (Hymenoptera: Encyrtidae) being the dominant taxon, while the other 10 species are probably hyperparasitoids, with a prevalence of Cheiloneurus nankingensis Li & Xu (Hymenoptera: Encyrtidae). These results indicate that parasitoid wasps associated with P. solenopsis from China are diverse and the integrated taxonomic approach applied in this study could enhance the accurate identification of these parasitoids that should be assessed in future biological control programs.

scholarly journals Quantitative Determination of the Surface Distribution of Supported Metal Nanoparticles: A Laser Ablation–ICP–MS Based Approach

Chemosensors ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 77
Author(s):  
Davide Spanu ◽  
Gilberto Binda ◽  
Marcello Marelli ◽  
Laura Rampazzi ◽  
Sandro Recchia ◽  
...  
Keyword(s):  
Spatial Distribution ◽  
Laser Ablation ◽  
Quantitative Determination ◽  
Metal Nanoparticles ◽  
Total Mass ◽  
Functional Materials ◽  
Metal Extraction ◽  
Ms Analysis ◽  
Icp Ms

A laser ablation–inductively coupled plasma–mass spectrometry (LA–ICP–MS) based method is proposed for the quantitative determination of the spatial distribution of metal nanoparticles (NPs) supported on planar substrates. The surface is sampled using tailored ablation patterns and the data are used to define three-dimensional functions describing the spatial distribution of NPs. The volume integrals of such interpolated surfaces are calibrated to obtain the mass distribution of Ag NPs by correlation with the total mass of metal as determined by metal extraction and ICP–MS analysis. Once this mass calibration is carried out on a sacrificial sample, quantifications can be performed over multiple samples by a simple micro-destructive LA–ICP–MS analysis without requiring the extraction/dissolution of metal NPs. The proposed approach is here tested using a model sample consisting of a low-density polyethylene (LDPE) disk decorated with silver NPs, achieving high spatial resolution over cm2-sized samples and very high sensitivity. The developed method is accordingly a useful analytical tool for applications requiring both the total mass and the spatial distribution of metal NPs to be determined without damaging the sample surface (e.g., composite functional materials and NPs, decorated catalysts or electrodic materials).

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