Soft Scale Research Articles

Resource-dependent mutual association with sap-feeders and a high predation rate in the ant Crematogaster scutellaris: help or harm in olive pest control?

Crematogaster scutellaris is a common tree-nesting ant in Mediterranean olive groves, where it acts as both predator and soft scale insect tender. We aimed to quantify the predatory action of this species and assess whether it influences the distribution of soft scale insects. Predation was investigated through experiments using live prey. The mutualistic relationship between ants and soft scales was assessed by supplementing sugar, amino acids or water to ant colonies, then monitoring for changes in scale tending activity. The probability of soft scale infestation on trees hosting or not hosting ant nests was also estimated. Predation rates on trees hosting a C. scutellaris nest were significantly higher than on trees without nests. Tending activity was affected by carbohydrate and, surprisingly, water availability. While the presence of C. scutellaris was significantly correlated to soft scale infestation, it also favoured predation towards other insects, suggesting a potential role in influencing different insect pests.

The cassava mealybug, Phenacoccus manihoti Matile-Ferrero (Hemiptera: Coccomorpha: Pseudococcidae) arrives in India.

Invasive species threaten the ecological and economic wellbeing of a country (Pimentel et al. 2001). In the last decade, several mealybugs and soft scale insects have been accidentally introduced to India, of which some have become serious pests (e.g., Phenacoccus solenopsis Tinsley, Paracoccus marginatus Williams Granara de Willink, Phenacoccus madeirensis Green and Pseudococcus jackbeardsleyi Gimpel Miller); others are widening their host ranges and spreading rapidly. Kilifia acuminata (Signoret) and Protopulvinaria longivalvata Green seem relatively harmless but Trijuba oculata (Brain) and Pulvinaria urbicola Cockerell cause economic damage (Joshi Rameshkumar 2013; Joshi 2017).

Grapevine Leaf Roll Disease and Grapevine Leaf Roll Associated Virus-3: A Review

Grapevine leaf roll disease has vast impact on productivity, growth and vigor of grapevine plant. This disease has alone caused more economic losses globally than any other known diseases of grapevines. It is responsible for damaging wine, grape juice, and table grape cultivars, as well as rootstocks. GLD is a complex disease, eleven viruses are associated with GLD (each named Grapevine leaf roll-associated virus followed by a number) which belongs to family Closteroviridae. Out of eleven GLD associated viruses Grapevine leaf roll-associated virus 3 (GLRaV-3) has major role in spreading GLD disease in grapevines. It belongs to genus Ampelovirus of Closteroviridae family. It is transmitted by grafting, vegetative propagation and insects like Mealybugs (Pseudococcidae) and soft scales (Coccidae). It is difficult to identify disease related viruses since most affected plants have mixed infection. It becomes further challenging when dissimilar viruses can cause similar symptoms. Low virus titer, uneven virus distribution in vineyards and symptomless rootstocks and white cultivars are common issues in mixed infections. This review summarizes origin, distribution, genomics and overall impact of (GLRaV-3) on grape plants and its importance related to GLD.

The genus Pulvinaria (Hemiptera: Coccomorpha: Coccidae) in China, with description of a new species and a new record.

A new species of soft scale insect (Hemiptera: Coccomorpha: Coccidae) in the genus Pulvinaria Targioni Tozzetti, 1866 is recorded from Yunnan, China on Pistacia chinensis Bunge. Pulvinaria pistaciae Cao Feng sp. n. is described and illustrated, based on adult female morphology. Pulvinaria decorata Borchsenius, 1957 is recorded for the first time from China (Henan and Shaanxi). A key to the adult females of Pulvinaria species known to occur in China is provided, and a table to show their distributions in various zoogeographical regions in China.

Underlying event measurements in p+p collisions at s=200 GeV at RHIC

Particle production sensitive to non-factorizable and non-perturbative processes that contribute to the underlying event associated with a high transverse momentum ($p_{T}$) jet in proton+proton collisions at $\sqrt{s}$=200 GeV is studied with the STAR detector. Each event is divided into three regions based on the azimuthal angle with respect to the highest-$p_{T}$ jet direction: in the leading jet direction ("Toward"), opposite to the leading jet ("Away"), and perpendicular to the leading jet ("Transverse"). In the Transverse region, the average charged particle density is found to be between 0.4 and 0.6 and the mean transverse momentum, $\langle p_{T}\rangle$, between 0.5-0.7 GeV/$c$ for particles with $p_{T}$$>$0.2 GeV/$c$ at mid-pseudorapidity ($|\eta|$$<$1) and jet $p_{T}$$>$15 GeV/$c$. Both average particle density and $\langle p_{T}\rangle$ depend weakly on the leading jet $p_{T}$. Closer inspection of the Transverse region hints that contributions to the underlying event from initial- and final-state radiation are significantly smaller in these collisions than at the higher energies, up to 13 TeV, recorded at the LHC. Underlying event measurements associated with a high-$p_{T}$ jet will contribute to our understanding of QCD processes at hard and soft scales at RHIC energies, as well as provide constraints to modeling of underlying event dynamics.

Debye Mass of Massless Φ4-Theory to Order g6 at Weak Coupling

The Debye mass is calculated to order g6 at weak coupling of massless ϕ4-theory. Debye mass gets contributions from the hard and soft momentum scale. We use dimensional reduction and the effective field theory to distinct two scales of order T and gT. Three dimensional effective theory is used to calculate contributions of soft scale whereas hard scale is evaluated by applying a perturbation theory, in power series of g. For the Debye mass to g6-order corrections, we calculate the hard part to g6 order and the soft part through mass parameter to g6 and calculate four loop self energy diagrams. The convergence of series and loop expansion are discussed.

Application simulation of the pulsed ultrasonic wave in soft scale removal of the heat exchange tube

It is a new descaling technology to use the ultrasonic wave to descale on the heat exchanger. The removal of the soft scale is an essential content of it. ANSYS\\DYNA is used to simulate the impact of ultrasonic on descaling in this paper. This paper aims at the simulation of a heat exchange tube by loading different ultrasonic cycles and frequencies. The results of the simulation show that the effect of descaling is the best when the number of cycles in a pulse is 5, and the impact of descaling gets better with the increase of ultrasonic frequency in a specific range.

An autoparasitoid wasp, inferior at resource exploitation, outcompetes primary parasitoids by using competitor females to produce males

1. Autoparasitoids are intraguild consumers that attack and kill heterospecific and conspecific parasitoids as well as immature stages of hemipteran hosts, such as aphids, whiteflies and soft scales. Field experiments assessing the importance of interspecific competition between autoparasitoids and primary parasitoids, as well as its impact on herbivore suppression, are scarcely found in the ecological literature.2. Using field data from 40 olive orchards, this study examined the mechanisms that regulate: (i) the interspecific competition between primary parasitoids of the genus Metaphycus and the autoparasitoid Coccophagus lycimnia; and (ii) the density of their shared herbivore host, the soft scale Saissetia oleae.3. Metaphycus parasitoids used smaller hosts than C. lycimnia, yet did not outcompete C. lycimnia. On the other hand, C. lycimnia preferred to use Metaphycus females as secondary hosts for producing males rather than their own females. This preference might explain why the autoparasitoid negatively affected the density of the primary parasitoids.4. Parasitism by the autoparasitoid C. lycimnia at the beginning of the season was the sole variable positively related to host mortality throughout the season, showing its greater effect on herbivore suppression.5. In this study, an autoparasitoid, inferior at resource exploitation, was shown to outcompete a primary parasitoid without disrupting herbivore suppression.

Citrus Pest Quick Guide: Brown Soft Scale

A one-page quick guide written by Lauren M. Diepenbrock and Jamie D. Burrow and published by the Entomology and Nematology Department presents the life cycle of brown soft scale and provides several photos of the pest and the damage it causes to assist in identification. https://edis.ifas.ufl.edu/in1252

Excretion of non-metabolized insecticides in honeydew of striped pine scale

Honeydew production is a characteristic of soft scales and other hemipteran insects. Honeydew has the capacity to alter the ecology of predators and parasitoids because it is used as a food resource and can contain insecticidal proteins from hemipteran host plants. We examined honeydew excreted by the striped pine scale (Hemiptera: Coccidae), Toumeyella pini (King), after feeding on pine trees treated with systemic insecticides to determine whether they could eliminate insecticidal compounds in honeydew. Imidacloprid and spirotetramat were applied at labeled rates to soil or foliage. Water sensitive paper was used to measure honeydew production and liquid chromatography coupled to mass spectrometry (LC-MS) to analyze excreted insecticide concentrations. Foliar and soil applications of imidacloprid caused a 25-fold reduction honeydew produced by scales six days after treatment (DAT). In contrast, spirotetramat treatments did not affect honeydew production. Parent compounds of both insecticides were detected in honeydew. However, on imidacloprid treated plants, these compounds were detected at similar concentrations in honeydew collected at 4 DAT from soil and foliar treatments. Imidacloprid was only detected from soil treatments at 8 DAT. Similarly, the spirotetramat parent compound was found 4 DAT after soil and foliar treatments, but only at 8 DAT in foliar treatments. At this time the concentration of spirotetramat in honeydew was six-fold higher than at 4 DAT. We conclude that striped pine scales excrete insecticides in honeydew even when the toxicant greatly reduces honeydew production. Honeydew excretion is thus a mechanism of bioaccumulation and has the potential to harm honeydew-feeding organisms.

Scale Insect Records from Ornamental Plants Help to Prioritize Plant Health Resource Development

Estimates about which scale insect species are most frequently encountered in U.S. landscapes and commercial production systems are largely anecdotal. This survey of records maintained across about 15 years within the National Plant Diagnostic Network (NPDN) National Data Repository (NDR) returned information from 10,671 records of 192 scale insect species and 23 suspected species that were associated with ornamental plants. This broad species diversity challenges our ability to effectively train diagnosticians, can confound species identification accuracy, and impedes outreach efforts and resource development. To help focus future efforts in the development of outreach resources and diagnostic training guides, lists were assembled that identified the 60 top-ranked soft, armored, mealybug, and other scale insect taxa most frequently diagnosed within NDR records. Diagnostic service records from Georgia, North Carolina, South Carolina, and Tennessee provided more extensive information regarding sites or client types from which submitted samples originated. Results are being used to develop web-based, image-rich guides to key scale insect taxa in the southeastern United States that will explain life cycles, behaviors, and biology for pest species. These web-based guides can be exploited to optimize pest management actions.

Volunteerism is Associated with Improved Student Soft Skills

In this study, we assessed student soft-skills after a 36-month long community service program in a Philippine private higher education institution. The Soft Skills-Graduate Attribute Scale was developed to measure professional competence, critical thinking skills, communication skills, lifelong learning, social and ethical responsibility, productivity, and interpersonal skills. Sixty (60) marine engineering students were purposively selected based on their participation in the various community service activities. The result shows that students who regularly volunteered have significantly higher measures of graduate attributes relating to professional competence, communication skills, and social and ethical responsibility as compared to non-regular and first-time volunteers. This study underscores the value of service learning programs in higher education in improving soft skills as well as the cross-cultural competencies of students in highly technical fields.

Praga e poder: história do “devorista das laranjeiras” (Açores, Portugal, 1840-1860)

The “orange tree devourer” (Coccus hesperidum, also known as the “Brown Soft Scale”) was the agent of a crisis with economic and political implications that affected orange production in the Azores between 1840 and 1860. This article analyzes the origin, expansion, and impact of the pest, and how island and central powers intervened very quickly to protect populations against pests and diseases in the context of Portuguese liberalism. There are differences between the responses in the three districts comprising the archipelago. The narrative addresses the historiography of epidemics in the first half of the nineteenth century, suggesting the influence of public health ideas on the genesis of nineteenth century phytopathological policies, of which his case is a pioneer.

Sources de résistance d'Opuntia spp. contre la cochenille à carmin, Dactylopius opuntiae, au Maroc

Sources of resistance of Opuntia spp. against the prickly pear cochineal Dactylopius opuntiae, in MoroccoThis article describes the screening of 248 genotypes of different species of Opuntia spp. for resistance to Dactylopius opuntiae (Hemiptera: Dactylopiidae). This cactus germplasm came from a collection maintained at the National Institute of Agronomic Research (INRA), Morocco. The objective of this research was to identify ecotypes or clones resistant to this cochineal in order to reconstitute the cactus orchards that have been totally devastated in several regions of the kingdom. Natural and artificial infestations from surrounding hedgerows were monitored on a one‐hectare plot planted with 744 cactus plants belonging to these 248 genotypes of Opuntia spp. The design of the experiment was a randomized complete block with three replicates. Data on the evolution of the vegetative state of the cactus plants, as well as their level of infestation with the cochineal, was collected regularly. The results show that only seven ecotypes (Marjana, Belara, Karama, Ghalia, Angad, Cherratia and Melk Zhar) proved to be resistant to the soft scale pest, compared to the rest of the 241 clones that were infested. The seven resistant ecotypes have been registered in the national cactus catalogue and a parcel of mother plants with this identified plant material resistant to D. opuntiae was established. These resistant ecotypes will be the subject of later studies of resistance mechansims (antibiosis and antixenosis) for the cochineal and also for research on genetic improvement of the cactus in Morocco.

Determination of suitable host plant for rearing of &lt;i&gt;Coccus hesperidum&lt;/i&gt; (Homoptera: Coccidae)

Brown soft scale, Coccus hesperidum Linnaues (Homoptera: Coccidae) is an economically important pest on wide range of horticultural and agricultural crops. A study was carried out to determine the suitability of three host plants, black nightshade (Solanum nigrum), mandarin (Citrus reticulata) and cotton (Gossypium barbadense), for mass rearing of C. hesperidum under laboratory conditions of 25±2 °C, 65±5% RH and photoperiod of 14D:10L. C. hesperidum was able to develop and reproduce on all three host plants. However, according to developmental period, longevity and fecundity, mandarin was the best among the three host plants.

Thermal radiation and inclusive production in the Kharzeev-Levin-Nardi model for ion-ion collisions

We show that in order to obtain a successful description of the transverse momenta distribution for charged particles in ion-ion collisions, one must include a thermal emission term. The temperature of this emission $T_{\rm th}$ turns out to be proportional to the saturation scale, $T_{\rm th} = 1.8/2\pi \,Q_s$. The formalism for the calculation of the transverse momenta spectra in CGC/saturation approach is developed, in which two stages of the process are seen: creation of the colour glass condensate, and hadronization of the gluon jets. Our calculations are based on the observation that even for small values of $p_T$, the main contribution in the integration over the dipole sizes stems from the kinematic region in vicinity of the saturation momentum, where theoretically, we know the scattering amplitude. Non-perturbativ corrections need to be included in the model of hadronization. This model incorporates the decay of a gluon jet with effective mass $m^2_{\rm eff} = 2 Q_s \mu_{\rm soft}$ where $\mu_{\rm soft}$ denotes the soft scale, with the fragmentation functions at all values of the transverse momenta. We use the KLN model which, provides a simple way to estimate the cross sections for the different centrality classes. Comparing the results of this paper with the transverse distribution in the proton-proton scattering, we see two major differences. First, a larger contribution of the thermal radiation term is needed, in accord with higher parton densities of the produced colour glass condensate. Second, even changing the model for the hadronization, without a thermal radiation term, we fail to describe the $p_T$ spectrum. Consequently, we conjecture that theexistence of the thermal radiation term is independent of the model of confinement.

Supersymmetric naturalness beyond MSSM

The experiments at the Large Hadron Collider (LHC) have pushed the limits on masses of supersymmetric particles beyond the ∼TeV scale. This compromises naturalness of the simplest supersymmetric extension of the Standard Model, the minimal supersymmetric Standard Model (MSSM). In this paper we advocate that perhaps the current experimental data are actually hinting towards the physics beyond MSSM. To illustrate this, we treat the MSSM as a low-energy limit of a more fundamental yet unspecified theory at a scale Λ, and compute the fine-tuning measure Δ for generic boundary conditions with soft SUSY breaking parameters and various cut-off scales. As a general trend we observe reduction in fine-tuning together with lowering Λ. In particular, perfectly natural [Δ ≲ mathcal{O} (10)] theories with a multi-TeV spectrum of supersymmetric particles that are consistent with all current observations can be obtained for Λ ∼ mathcal{O} (100)TeV. The lowering of the fine-tuning for large cut-off scales can also be observed in theories exhibiting special quasi-fixed point behaviour for certain parameters. Our observations call for a more thorough exploration of possible alternative ultraviolet completions of MSSM.

Erratum: Addendum to Zootaxa 4612 (3): On some new and old soft scale insects (Hemiptera: Coccomorpha: Coccidae) from Africa, with description of a new Coccus species and introduction of a new genus by B. Łagowska and Chris J. Hodgson.

Due to an oversight, the depositories of the new species, Coccus giliomeei Łagowska Hodgson, and of the new material of Coccus rhodesiensis (Hall) collected in the Transvaal, South Africa, was omitted from the manuscript. Both lots of slides will be deposited in SANC, The South African National Collection of Insects, Pretoria, South Africa.

Revisiting the SUSY μ problem and its solutions in the LHC era

The supersymmetry preserving mu parameter in SUSY theories is naively expected to be of order the Planck scale while phenomenology requires it to be of order the weak scale. This is the famous SUSY mu problem. Its solution involves two steps: 1. first forbid mu, perhaps via some symmetry, and then 2. re-generate it of order the scale of soft SUSY breaking terms. However, present LHC limits suggest the soft breaking scale m_{soft} lies in the multi-TeV regime whilst naturalness requires mu~ m_{W,Z,h}~ 100 GeV so that a Little Hierarchy (LH) appears with mu << m_{soft}. We review twenty previously devised solutions to the SUSY mu problem and re-evaluate them in light of whether they are apt to support the LH. We organize the twenty solutions according to: 1. solutions from supergravity/superstring constructions, 2. extended MSSM solutions, 3. solutions from an extra local U(1)' and 4. solutions involving Peccei-Quinn (PQ) symmetry and axions. Early solutions would invoke a global Peccei-Quinn symmetry to forbid the mu term while relating the mu solution to solving the strong CP problem via the axion. We discuss the gravity-safety issue pertaining to global symmetries and the movement instead toward local gauge symmetries or R-symmetries, either continuous or discrete. At present, discrete R-symmetries of order M (Z_M^R) which emerge as remnants of Lorentz symmetry of compact dimensions seem favored. Even so, a wide variety of regenerative mechanisms are possible, some of which relate to other issues such as the strong CP problem or the generation of neutrino masses. We also discuss the issue of experimental verification or falsifiability of various solutions to the mu problem. Almost all solutions seem able to accommodate the LH.

Development of sensitive molecular assays for the detection of grapevine leafroll-associated virus 3 in an insect vector.

Grapevine leafroll-associated virus 3 (GLRaV-3) is an economically significant virus of grapevines, with secondary spread mediated by several species of mealybug and soft scale insects. To better understand virus-vector interactions, sensitive virus detection in these insects is a key tool. In this research, two new hydrolysis-probe-based real-time assays for GLRaV-3 detection were developed and compared to three existing assays. Of the five assays compared, the one-step RT-qPCR probe-based assay was the most sensitive and reliable, with as few as 10 virus RNA copies detected. This is the first description of a real-time molecular assay for virus detection in mealybugs with such sensitivity.