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Candidatus Liberibacter asiaticus ( C Las) is one of the putative causal agents of huanglongbing, which is a serious disease in citrus production. The pathogen is transmitted by Diaphorina citri Kuwayama (Hemiptera: Psyllidae). As an observational study, six groves in central Florida and one grove at the southern tip of Florida were sampled monthly from January 2008 through February 2012 (50 months). The collected psyllids were sorted by sex and abdominal color. Disease prevalence in adults peaked in November, with a minor peak in February. Gray/brown females had the highest prevalence, and blue/green individuals of either sex had the lowest prevalence. C Las prevalence in blue/green females was highly correlated with the prevalence in other sexes and colors. Thus, the underlying causes for seasonal fluctuations in prevalence operated in a similar fashion for all psyllids. The pattern was caused by larger nymphs displacing smaller ones from the optimal feeding sites and immunological robustness in different sex-color morphotypes. Alternative hypotheses were also considered. Improving our understanding of biological interactions and how to sample them will improve management decisions. We agree with other authors that psyllid management is critical year-round.

AbstractThe starfish family Asterinidae shows a diversity of reproductive modes, and a number of species have sufficient life-history data that can be used for analysis, using life-cycle graphs. These include four species that reproduce by fission ( Aquilonastra yairi , Nepanthia belcheri , Aquilonastra burtonii , and Ailsastra heteractis ), a viviparous species ( Parvulastra vivipara ), two species with benthic egg masses ( Asterina gibbosa and Asterina phylactica ), one with planktonic larvae that do not feed ( Cryptasterina pentagona ), and one with larvae that feed in the plankton ( Patiria miniata ). Species are compared using adult and first-year survival and, for some species, the age at first reproduction, number of offspring (eggs or newly released juveniles), and individual growth parameters of the von Bertalanffy model. The sensitivity of population growth, fitness, to changes in these traits is shown by elasticity analysis, which aids in understanding possible consequences of environmental forces as well as possible directions of selection.

The glassy-winged sharpshooter, Homalodisca vitripennis (Germar) (Hemiptera: Cicadellidae: Cicadellinae), is an introduced vector of the xylem-dwelling bacterium Xylella fastidiosa Wells et al. (Xanthomonadales: Xanthomonadaceae) in California. Once acquired, X. fastidiosa colonizes the functional foregut of the vector. Bacteria can be inoculated directly into grapevine xylem during the xylem cell acceptance process in sharpshooter stylet probing, represented by the X wave using electropenetrography (EPG). Since 2001, an effort has been underway to develop PD-resistant grapevines, Vitis vinifera L., through classical breeding of various species of resistant wild grapevines with more susceptible V. vinifera. The present study used EPG to compare H. vitripennis stylet probing behaviors in a factorial experiment between V. champinii (a V. candicans/V. rupestris natural hybrid with moderate trichomes) and V. vinifera cv. 'Chardonnay' (which lacks trichomes) that had been gently scraped to remove trichomes or was not scraped. Results showed that sharpshooters performed significantly more X waves/X. fastidiosa inoculation behaviors of overall longer duration on Chardonnay than on V. champinii, regardless of shaving or not-shaving to remove trichomes. In addition, trichomes caused more frequent standing/walking/test-probing behaviors on V. champinii, whose xylem was rapidly accepted for sharpshooter ingestion once probing began. Thus, EPG can detect a novel type of grapevine resistance to X. fastidiosa-to the vector's probing process and inoculation of bacteria-in addition to the bacterial infection and symptom development processes that are the basis for most resistance breeding today. Future research could use EPG to screen grapevines for this novel type of resistance., (Published by Oxford University Press on behalf of Entomological Society of America 2021.)

Huanglongbing is a citrus disease that reduces yield, crop quality, and eventually causes tree mortality. The putative causal agent, Candidatus Liberibacter asiaticus (Rhizobiales: Rhizobiaceae), is vectored by the Asian citrus psyllid, Diaphorina citri Kuwayama. Disease management is largely through vector control, but the insect is developing pesticide resistance. A nonchemical approach to vector management is to grow citrus under screen cages either as bags over individual trees or enclosures spanning many acres. The enclosing screen reduces wind, alters temperature relative to ambient, and excludes a variety of pests that are too large to pass through the screen. Here we evaluated the potential of six screens to exclude D. citri. We conclude that screens with rectangular openings need to limit the short side to no more than 384.3 µm with a SD of 36.9 µm (40 mesh) to prevent psyllids from passing through the screen. The long side can be at least 833 µm, but the efficacy of screens exceeding this value should be tested before using in the field., (© The Author(s) 2020. Published by Oxford University Press on behalf of Entomological Society of America.)

Insecticide resistance is an increasing problem in citrus production. The Asian citrus psyllid, Diaphornia citri Kuwayama, is recognized as one of the most important citrus pests worldwide and it has developed resistance in areas where insecticides have been overused. The development of insecticide resistance is often associated with fitness costs that only become apparent in the absence of selection pressure. Here, the fitness costs associated with resistance to thiamethoxam and imidacloprid were investigated in three agricultural populations of D. citri as compared with susceptible laboratory colonies. Results showed that all field populations had greater resistance than laboratory susceptible colonies. For both thiamethoxam and imidacloprid, a Candidatus Liberibacter asiaticus-positive (CLas+) colony was more susceptible than the CLas- colony. Resistance ratios ranged from 7.65-16.11 for imidacloprid and 26.79-49.09 for thiamethoxam in field populations as compared with a susceptible, CLas- laboratory strain. Among three resistant field populations, a significantly reduced net reproductive rate and finite rate of population increase were observed in a population from Lake Wales, FL as compared to both susceptible strains. The fecundity of field populations from Lake Wales, FL was statistically lower than both laboratory susceptible populations. Certain changes in morphological characteristics were observed among resistant, as compared, with susceptible strains. Our data suggest fitness disadvantages associated with insecticide resistance in D. citri are related to both development and reproduction. The lower fitness of D. citri populations that exhibit resistance to neonicotinoid insecticides should promote recovery of sensitivity when those populations are no longer exposed to thiamethoxam and/or imidacloprid in the field. The results are congruent with a strategy of insecticide rotation for resistance management.

Candidatus Liberibacter asiaticus Jagoueix, Bové, and Garnier (Rhizobiales: Rhizobiaceae) is transmitted by the psyllid Diaphorina citri Kuwayama and putatively causes Huanglongbing disease in citrus. Huanglongbing has reduced yields by 68% relative to pre-disease yields in Florida. Disease management is partly through vector control. Understanding vector biology is essential in this endeavor. Our goal was to document differences in probing behavior linked to sex. Based on both a literature review and our results, we conclude that there is either no effect of sex or that identifying such an effect requires a sample size at least four times larger than standard methodologies. Including both color and sex in statistical models did not improve model performance. Both sex and color are correlated with body size, and body size has not been considered in previous studies on sex in D. citri in terms of probing behavior. An effect of body size was found wherein larger psyllids took longer to reach ingestion behaviors and larger individuals spent more time-ingesting phloem, but these relationships explained little of the variability in these data. We suggest that the effects of sex can be ignored when running EPG experiments on healthy psyllids., (© The Author(s) 2020. Published by Oxford University Press on behalf of Entomological Society of America.)

Insects can be effective vectors of plant diseases and this may result in billions of dollars in lost agricultural productivity. New, emerging or introduced diseases will continue to cause extensive damage in afflicted areas. Understanding how the vector acquires the pathogen and inoculates new hosts is critical in developing effective management strategies. Management may be an insecticide applied to kill the vector or a host plant resistance mechanism to make the host plant less suitable for the vector. In either case, the tactic must act before the insect performs the key behavior(s) resulting in either acquisition or transmission. This requires knowledge of the timing of behaviors the insect uses to probe the plant and commence ingestion. These behaviors are visualized using electropenetrography (EPG), wherein the plant and insect become part of an electrical circuit. With the tools to define specific steps in the probing process, we can understand the timing of acquisition and inoculation. With that understanding comes the potential for more relevant testing of management strategies, through insecticides or host plant resistance. The primary example will be Candidatus Liberibacter asiaticus transmitted by Diaphorina citri Kuwayama in the citrus agroecosystem, with additional examples used as appropriate.

Negative senescence, a decrease in size-specific mortality of large individuals, is shown by sea urchins. Sea urchins have indeterminate growth and size-specific gamete production increases throughout life. These characteristics are present in short-lived species, Lytechinus pictus and L. variegatus as well as ones that are long-lived: Mesocentrotus franciscanus, Strongylocentrotus purpuratus, Echinometra mathaei, and Stomopneustes variolaris. Both short and long-lived species have cellular mechanisms that counter senescence. Many groups of organisms have species that are short-lived as well species with individuals that may attain ages of many hundreds of years. Generally it is assumed that short-lived species show senescence but results for sea urchins indicate that lack senescence may be present even when mortality is high., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Two juvenile specimens of a new species of Oreaster were collected at Parque Nacional Arrecife Alacranes and Triángulos Oeste in the southern Gulf of Mexico. DNA of mitochondrial loci identifies them as members of the same clade as cloning larvae of Oreaster found abundantly in waters of the Florida Current-Gulf Stream system, and distinct from Oreaster clavatus and Oreaster reticulatus , the two known Oreasteridae species in the North Atlantic. Larvae from the new species of Oreaster persist as clones but also metamorphose and settle to the benthos with typical asteroid morphology.

Insect vector behavior and biology can be affected by pathogen-induced changes in the physiology and morphology of the host plant. Herein, we examined the temporal effects of Squash vein yellowing virus (family Potyviridae, genus Ipomovirus) infection on the settling, oviposition preference, and feeding behavior of its whitefly vector, Bemisia tabaci (Gennadius) Middle East-Asia Minor 1 (MEAM1), formerly known as B. tabaci biotype B. Settling and oviposition behavioral choice assays were conducted on pairs of infected and mock-inoculated watermelon (Citrullus lanatus (Thunb) Matsum and Nakai) (Cucurbitales: Cucurbitaceae) at 5-6 days post inoculation (DPI) and 10-12 DPI. Electropenetrography, or electrical penetration graph (both abbreviated EPG), was used to assess differences in feeding behaviors of whitefly on mock-inoculated, 5-6 and 10-12 DPI infected watermelon plants. Whiteflies showed no preference in settling or oviposition on the infected and mock-inoculated plants at 5-6 DPI. However, at 10-12 DPI, whiteflies initially settled on infected plants but then preference of settling shifted to mock-inoculated plants after 8 h. Only at 10-12 DPI, females laid significantly more eggs on mock-inoculated plants than infected plants. EPG revealed no differences in whitefly feeding behaviors among mock-inoculated, 5-6 DPI infected and 10-12 DPI infected plants. The results highlighted the need to examine plant disease progression and its effect on vector behavior and performance, which could play a crucial role in Squash vein yellowing virus spread., (© The Author(s) 2019. Published by Oxford University Press on behalf of Entomological Society of America.)

The Asian citrus psyllid, Diaphorina citri Kuwayama (Hemiptera: Liviidae) is the vector of Candidatus Liberibacter asiaticus (CLas), the presumed cause of Huanglongbing (HLB) in citrus. Management strategies were developed in Florida that used soil-applied neonicotinoids to protect young trees. Despite the implementation of intense management programs, infection spread among the most intensively managed groves. We used electopenetrography to test five imidacloprid doses (0.55, 5.5, 55, 550, and 5,500 ppm) administered in artificial diet to approximate the dosage required to reduce feeding activity and prevent salivation/ingestion activity. We failed to detect a significant effect of 0.55 ppm imidacloprid on probing behavior, pathway, or salivation/ingestion activity when compared with the untreated control. We observed a significant reduction in the number of probes and the number of pathway with both 5.5 and 55 ppm imidacloprid. We detected a significant reduction in the number of salivation/ingestion events at both 5.5 ppm and 55 ppm imidacloprid (57 and 54 percent, respectively) compared with the untreated control, and a reduction in number of sustained (>600 s) salivation/ingestion at 55 ppm. While reductions in feeding activity were apparent at dosages of at least 5.5 ppm, we were unable to prevent salivation/ingestion with dosages as high as 5,500 ppm, which is greater than what is known to occur following application in the field. While soil-applied imidacloprid may slow the spread of CLas, our findings suggest that prevention of CLas inoculation in the field is unlikely. Management strategies must be refined to prevent the spread of HLB in Florida., (© The Author(s) 2019. Published by Oxford University Press on behalf of Entomological Society of America.)

Electropenetrography a.k.a. electrical penetration graph or EPG is a rigorous technique for studying arthropod behavior. Essentially, the arthropod and host are part of an electrical circuit that generates patterns of voltage (waveforms), whose biological meanings are defined by correlation with histology and behavior. EPG is used for studying stylet probing behavior of hemipterans, and blood-feeding arthropods. These results are applied to understanding pesticide action, host plant resistance, and vector-pathogen-host interactions. At the end of all recordings, the arthropod begins a behavior that ends because the scientist stopped recording. An argument for keeping this event in the data has been made based on the assumption that the insect is adapting to laboratory conditions. In this adaptation process, the expected durations of ingestion behaviors will increase as the insect adapts. We show that this assumption can cause problems in data analysis and interpretation of the data. If the assumption is false, then there are more options for analyzing the data. Deleting artificially terminated events can be advantageous, but the best approach needs to consider the biology of the arthropod and align with research objectives., (Published by Oxford University Press on behalf of Entomological Society of America 2018.)

Size, growth, and density have been studied for North American Pacific coast sea urchins Strongylocentrotus purpuratus, S. droebachiensis, S. polyacanthus, Mesocentrotus (Strongylocentrotus) franciscanus, Lytechinus pictus, Centrostephanus coronatus, and Arbacia stellata by various workers at diverse sites and for varying lengths of time from 1956 to present. Numerous peer-reviewed publications have used some of these data but some data have appeared only in graduate theses or the gray literature. There also are data that have never appeared outside original data sheets. Motivation for studies has included fisheries management and environmental monitoring of sewer and power plant outfalls as well as changes associated with disease epidemics. Studies also have focused on kelp restoration, community effects of sea otters, basic sea urchin biology, and monitoring. The data sets presented here are a historical record of size, density, and growth for a common group of marine invertebrates in intertidal and nearshore environments that can be used to test hypotheses concerning future changes associated with fisheries practices, shifts of predator distributions, climate and ecosystem changes, and ocean acidification along the Pacific Coast of North America and islands of the north Pacific. No copyright restrictions apply. Please credit this paper when using the data., (© 2017 by the Ecological Society of America.)

Diaphorina citri is a major pest of citrus because it transmits Candidatus Liberibacter asiaticus, a phloem-limited bacterium that putatively causes Huanglongbing (HLB). The disease moves slowly through a tree, and the vector facilitates further within-tree movement via transmission of the pathogen. However, this only happens when D. citri stylets contact the phloem, to inoculate bacteria during phloem salivation and acquire bacteria during phloem sap ingestion. Behavioral changes in D. citri associated with different plant parts would affect how long it takes to reach phloem and how long the psyllids stays in phloem to ingest, thereby influencing the risk of disease spread. D. citri feeding was recorded on the abaxial and adaxial surfaces of mature and immature citrus leaves. Adults in the field can be found on these surfaces at all times of year. On abaxial surface of immature leaves, phloem salivation would occur after 11 h on average, but rarely as soon as 0.56 h. The corresponding values on mature leaves were 16 and 2.7. In general, psyllids spent more time ingesting phloem sap on immature leaves than on mature leaves. Psyllids on abaxial surfaces spent more time ingesting from phloem, though the strength of this effect was less than for immature versus mature leaves. In contrast, xylem ingestion increased on mature leaves compared with young. The biological differences that could produce this outcome are discussed. The results discussed herein are of relevance to further studies on the efficacy of an insecticide to act quickly enough to prevent pathogen transmission., Competing Interests: Compliance with ethical standardsMention of trade names or commercial products in this article is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the U.S. Department of Agriculture. USDA is an equal opportunity provider and employer.

In the Asian citrus psyllid (Diaphorina citri Kuwayama), learning facilitates host recognition and mate preference; however, it is unclear whether induced female oviposition preference occurs in this species. We investigated the influence of natal host experience on adult oviposition preference when reared on either 'Valencia' orange (Citrus x sinesis) or orange jasmine (Murraya paniculata). Psyllids reared on 'Valencia' orange preferred 'Valencia' orange as an oviposition host compared with orange jasmine, whereas there was no difference in oviposition between the two hosts in orange jasmine reared psyllids. Nymphs transferred from 'Valencia' orange to orange jasmine were smaller in adult size and required more time for development. These findings were reversed in orange jasmine reared psyllids, which increased in size and displayed shorter development times when transferred from orange jasmine to 'Valencia' orange. However, mortality increased in nymphs transferred to the non-natal host species in both treatment groups compared with nymphs transferred to the same host. These results indicate an association between host plant preference and performance in this species. Maternal host experience appeared to influence the oviposition preference in this species. Juvenile psyllid performance appeared negatively affected by orange jasmine plants such that fitness was reduced, suggesting benefits for maternal host fidelity in those insects not acclimated to feeding on orange jasmine. Induced oviposition preference may provide an important mechanism of adaptive plasticity in D. citri reproductive strategies, allowing females to discriminate among potential host species in favor of those to which her offspring are best adapted., (© The Author 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Insect-transmitted plant-pathogenic bacteria may alter their vectors' fitness, survival, behavior, and metabolism. Because these pathogens interact with their vectors on the cellular and organismal levels, potential changes at the biochemical level might occur. " Candidatus Liberibacter asiaticus" ( C Las) is transmitted in a persistent, circulative, and propagative manner. The genome of C Las revealed the presence of an ATP translocase that mediates the uptake of ATP and other nucleotides from medium to achieve its biological processes, such as growth and multiplication. Here, we showed that the levels of ATP and many other nucleotides were significantly higher in C Las-infected than healthy psyllids. Gene expression analysis showed upregulation for ATP synthase subunits, while ATPase enzyme activity showed a decrease in ATPase activity. These results indicated that C Las stimulated Diaphorina citri to produce more ATP and many other energetic nucleotides, while it may inhibit their consumption by the insect. As a result of ATP accumulation, the adenylated energy charge (AEC) increased and the AMP/ATP and ADP/ATP ratios decreased in C Las-infected D. citri psyllids. Survival analysis confirmed a shorter life span for C Las-infected D. citri psyllids. In addition, electropenetrography showed a significant reduction in total nonprobing time, salivation time, and time from the last E2 (phloem ingestion) to the end of recording, indicating that C Las-infected psyllids were at a higher hunger level and they tended to forage more often. This increased feeding activity reflects the C Las-induced energetic stress. In conclusion, C Las alters the energy metabolism of its psyllid vector, D. citri , in order to secure its need for energetic nucleotides. IMPORTANCE Insect transmission of plant-pathogenic bacteria involves propagation and circulation of the bacteria within their vectors. The transmission process is complex and requires specific interactions at the molecular and biochemical levels. The growth of the plant-pathogenic bacteria in the hemolymph of their vectors indicated that the hemolymph contains all the necessary nutrients for their growth. In addition to nutrients, " Candidatus Liberibacter asiaticus" ( C Las) can take up energetic nucleotides, such as ATP, from its vector, Diaphorina citri , using ATP translocase. In this study, we found that the C Las pathogen manipulates the energy metabolism of its insect vector. The accumulation of ATP in C Las-infected D. citri psyllids indicated that C Las induces ATP production to fulfill its need for this energetic compound. As a result of ATP accumulation, a shorter life span and altered feeding behavior were observed. These findings increase our knowledge of insect transmission of the persistent-circulative-propagative type of plant pathogens vectored by insects., (Copyright © 2017 American Society for Microbiology.)

Adults, immatures and eggs of Tuckerella japonica (Ehara) were collected from unknown clones or varieties of Camellia sinensis (L.) O. Kuntze tea bushes in the Clemson University Farm, Coastal Research and Education Center, Charleston, South Carolina; from Assam hybrids in The Caw Caw Nature Preserve in Ravenel, SC; from C. sinensis and C. assamica (Masters) in the Charleston Tea Plantation on Wadmalaw Island, SC; C. sinensis in the Fairhope Tea Plantation in Fairhope, Alabama; and from C. sinensis 'Rosea' and a C. sinensis and C. assamica hybrid in Savannah and Ellabell, Georgia, between 1994 and 2015. This mite was consistently collected from 1-, 2- and 3+-year-old wood of tea plants with significantly greater numbers collected from 2-year-old wood. All stages of the mite were found within longitudinally split areas of the wood where underlying green bark tissues were exposed. As 1-year-old wood matured, there was increased splitting of the bark with increased mite presence. Mature green fruit (= developing seed pods) of tea were also frequented by T. japonica between June-July and October and their numbers were no greater than those on 1- or 3+-year wood. When the fruit were small (March-May) or as they hardened in late fall, they were not suitable feeding sites for this mite. Very few T. japonica were collected from 50 mature, inner or outer leaf samples with none usually found. Tuckerella japonica has multiple, overlapping generations and occurs on tea throughout the year in Alabama, Georgia and South Carolina, USA.

A Skinner mercury vapor light trap was operated from 2001 through 2009 in a residential backyard to document biodiversity within the moth families Thyatiridae, Drepanidae, Geometridae, Mimallonidae, Apatelodidae, Lasiocampidae, Saturniidae, Sphingidae, Erebidae (including Lymantriinae and Arctiinae), Euteliidae, Nolidae, and Noctuidae. When making comparisons to older literature, we recalculated our results to conform to the older classification of the Noctuoidea. Moths were released after identification. There were 501 species documented in 77581 captures from 1290 sampling dates. There was a perceived risk that released moths would fly back into the trap the following evening. This should result in an abnormal number of rare moths that are caught multiple times. The number of species caught twice versus the number caught once was no different than a similar ratio for surveys that used more traditional sampling methods. Therefore this concern does not seem to be valid for these data. These data are provided in a supplementary file available for download. There were three previous surveys conducted in nearby natural areas. They documented fewer species than were documented here. To understand this better, we examined several specialized groups of moths that tend to use host plants not typically found in an urban residential yard. More species in Schinia Hübner, Catocala Schrank, Acronicta Ochsenheimer, and Herminiinae Leech were found in this survey than the other local surveys. Only in the Papaipema Smith did we recover fewer species, though it was still above 70% of what was expected. This diversity could be a result of sampling effort, but it shows that this urban location has a very diverse moth fauna. We suggest that this diversity is partly due to the planting of native plant species in the area about the light trap. Therefore we would concur with others that urban landscapes can be planned to increase biodiversity relevant to more natural ecosystems. In this study we looked at the ratio of the number of species of Geometridae divided by the number of species of Noctuidae as one approach to evaluating the level of disturbance in the moth assemblage. Although the yearly average was nearly constant, the seasonal ratio ranged from 0.09 to 0.91 depending on the sampling date. We also calculated alpha diversity and found that seasonal change in alpha diversity greatly exceeded yearly differences. This strong seasonal component means that a comparison between two studies requires a correction for seasonality and similar sampling intervals. In this study, a shift of two weeks would be sufficient to result in a significant difference in alpha diversity. This is the equivalent of increasing temperature by 1.53 °C. Seasonal shifts limit the usefulness of this methodology for environmental assessment because the within season change exceeds the between season change. This problem is compounded when sampling designs interact with this seasonality. In describing our data, we made use of a growing degree day (GDD) model. This approach corrects for simple temperature dependent shifts in moth biology. Consequently, some of the variability in the data was removed, which should improve the power of statistical tests involving survey data. If sampling protocols were based on growing degree days rather than calendar dates, the bias caused by temperature induced shifts in seasonal cycles could be reduced.

Background: Huanglongbing (HLB) or citrus greening is a devastating disease of citrus. The gram-negative bacterium Candidatus Liberibacter asiaticus (Las) belonging to the α-proteobacteria is responsible for HLB in North America as well as in Asia. Currently, there is no cure for this disease. Early detection and quarantine of Las-infected trees are important management strategies used to prevent HLB from invading HLB-free citrus producing regions. Quantitative real-time PCR (qRT-PCR) based molecular diagnostic assays have been routinely used in the detection and diagnosis of Las. The oligonucleotide primer pairs based on conserved genes or regions, which include 16S rDNA and the β-operon, have been widely employed in the detection of Las by qRT-PCR. The availability of whole genome sequence of Las now allows the design of primers beyond the conserved regions for the detection of Las explicitly., Results: We took a complimentary approach by systematically screening the genes in a genome-wide fashion, to identify the unique signatures that are only present in Las by an exhaustive sequence based similarity search against the nucleotide sequence database. Our search resulted in 34 probable unique signatures. Furthermore, by designing the primer pair specific to the identified signatures, we showed that most of our primer sets are able to detect Las from the infected plant and psyllid materials collected from the USA and China by qRT-PCR. Overall, 18 primer pairs of the 34 are found to be highly specific to Las with no cross reactivity to the closely related species Ca. L. americanus (Lam) and Ca. L. africanus (Laf)., Conclusions: We have designed qRT-PCR primers based on Las specific genes. Among them, 18 are suitable for the detection of Las from Las-infected plant and psyllid samples. The repertoire of primers that we have developed and characterized in this study enhanced the qRT-PCR based molecular diagnosis of HLB.

A wide variety of organisms show morphologically plastic responses to environmental stressors but in general these changes are not reversible. Though less common, reversible morphological structures are shown by a range of species in response to changes in predators, competitors or food. Theoretical analysis indicates that reversible plasticity increases fitness if organisms are long-lived relative to the frequency of changes in the stressor and morphological changes are rapid. Many sea urchin species show differences in the sizes of jaws (demi-pyramids) of the feeding apparatus, Aristotle's lantern, relative to overall body size, and these differences have been correlated with available food. The question addressed here is whether reversible changes of relative jaw size occur in the field as available food changes with season. Monthly samples of the North American Pacific coast sea urchin Strongylocentrotus purpuratus were collected from Gregory Point on the Oregon (USA) coast and showed an annual cycle of relative jaw size together with a linear trend from 2007 to 2009. Strongylocentrotus purpuratus is a long-lived species and under field conditions individuals experience multiple episodes of changes in food resources both seasonally and from year to year. Their rapid and reversible jaw plasticity fits well with theoretical expectations.

The purpose of this investigation was to evaluate acquisition and inoculation (together, transmission) efficiency of Candidatus Liberibacter asiaticus (Las), the pathogen associated with citrus huanglongbing (HLB) by the Asian citrus psyllid, Diaphorina citri (Kuwayama) (Hemiptera: Psyllidae). In laboratory studies, nymphs reared on Las infected plants were more likely to acquire the bacterium than adults. Acquisition by nymphs ranged from 60 to 100%, whereas acquisition by adults only reached 40% after 5 wk of feeding on Las-infected plants. Similar rates of pathogen acquisition by psyllids after nymphal and adult feeding were observed in the field. Transmission of Las from parent to offspring (transovarial) occurred at a rate of 2-6%. One year after psyllid inoculations, successful transmission by individual D. citri ranged from 4 to 10%, whereas groups of 100 or more D. citri transmitted the pathogen at a rate of approximately 88%. In addition, the proportion of Las-positive adult psyllids, determined using quantitative real-time polymerase chain reaction, decreased over time when held on healthy plants. Due to the low rate of pathogen acquisition and long time period required for successful inoculation by adult D. citri, experiments designed to determine the latent period required for replication and successful inoculation of Las by D. citri did not result in Las-infected plants after >1 yr of incubation after inoculation. Collectively, these results indicate that adult D. citri which acquire the HLB pathogen as adults are poor vectors of the pathogen compared with adults that acquired the pathogen as nymphs.

The red sea urchin Strongylocentrotus franciscanus is a long-lived species and may live in excess of 100 years based on tagging studies in the field and corroboration from radiocarbon analyses as reported in the literature. Size-specific survival estimates reported here show no change in annual survival probability across the 6 largest 0.5 cm size classes from 14.6 to 18.1cm. In addition to no change in survival probability there is no reduction in reproductive capacity with size. Red sea urchins show no evidence of senescence and so do not fit well within the context of the disposable soma theory of the evolution of longevity.

Three sprayers were evaluated for their affect on retention and efficacy: a carbon dioxide powered high-volume sprayer, a DRAMM coldfogger, and an Electrostatic Spraying Systems (ESS) sprayer with air-assistance. The active ingredients used were spinosad and azadirachtin. The plant canopy was constructed in the greenhouse using potted soybeans (Glycine max (L) Merrill cr Pioneer 9392). Application efficacy with spinosad was assessed using thrips [Western flower thrips, Frankliniella occidentalis (Pergande)] and mite (two-spotted spider mite, Tetranychus urticae Koch) abundance on shoots and leaves. Application efficacy with azadirachtin was assessed using thrips and aphid (soybean aphid, Aphis glycines Matsumura) abundance on shoots and leaves. The atomization characteristics of each sprayer were measured using an Aerometrics phase/Doppler particle analyzer (PDPA) 100-1D. The results of four tests are presented. Two tests used each sprayer according to manufacturer recommendations. These are 'recommended volume' tests that confound differences in toxicant distribution caused by the sprayer with differences caused by changes in application volume. The other two tests were 'constant volume' tests in which all three sprayers were used to deliver the same application volume. Both types of test gave differences between sprayers in retention of toxicant, but only the recommended volume tests showed significant effects of the sprayers on pest abundance. We attribute this difference to the role played by changing application volumes in the dose-transfer process. The constant-volume tests showed that application equipment influences efficacy.

Purpose: We determine the sensitivity and specificity of various assays for the detection of urothelial carcinoma., Materials and Methods: A total of 280 voided urine specimens from 265 patients were obtained immediately before cystoscopy for BTA stat, (Bard Diagnostic, Redmond, Washington) hemoglobin dipstick, (Bayer, Elkhart, Indiana) telomerase and UroVysion (Vysis, a wholly owned subsidiary of Abbott Laboratories, Abbott Park, Illinois) analysis., Results: Of the 265 patients 75 had biopsy proven urothelial carcinoma, and the sensitivity of the assays was determined from these patients. From most sensitive to least sensitive, the overall sensitivity of UroVysion (73 cases), BTA stat (72), hemoglobin dipstick (73) and telomerase (70) was 81%, 78%, 74%, and 46%, respectively. Each of the first 3 tests was statistically significantly more sensitive than the telomerase assay (p <0.05). However, the differences in overall sensitivity of UroVysion, BTA stat and hemoglobin dipstick were not statistically significant. The specificity of the tests was calculated for 80 of the 265 patients in this study who had no history of urothelial carcinoma and negative cystoscopy findings despite common urological complaints. From most specific to least specific, the specificity of UroVysion, telomerase, BTA stat and hemoglobin dipstick was 96%, 91%, 74% and 51%, respectively. UroVysion and telomerase were statistically significantly (p <0.01) more specific than the BTA stat and hemoglobin dipstick assays, and all of the assays were more specific than hemoglobin dipstick testing (p <0.001)., Conclusions: Our study reveals that UroVysion is the most sensitive and specific assay among those tested for the detection of urothelial carcinoma. Telomerase testing had good specificity but poor sensitivity. The BTA stat and hemoglobin dipstick tests had good sensitivity but relatively poor specificity. UroVysion is a promising new assay for the detection of urothelial carcinoma in urine specimens. However, further studies are needed to explore the role of the various assays in the treatment of patients with superficial urothelial carcinoma.

New assay development should be directed toward answering fundamental clinical questions. Caveats that must be considered before initiating assay development projects are: New assays should allow the clinician to interact with and treat a patient more effectively, thereby improving medical outcome; and new assays should facilitate recapture of system resources, enabling cost savings or reinvestment of resources. Defining the clinical questions and consideration of the caveats permit a means of prioritizing assay development activities. Laboratorians are faced with evaluating several types of development activities that lead to assay implementation in routine clinical testing. Assays can be prioritized for up-grading to newer cost-effective technologies, provided the changes maintain or improve analytical and clinical performance. Predicting which research assay will have future value is difficult when clinical performance is not fully validated. However, such assay development has the greatest potential for changing the delivery of healthcare by a clinician.

An analysis for an age-structured demography was conducted to explore the sensitivity of fitness to individual parameters of a growth equation (Brody-Bertalanffy) and a survivorship function (Weibull). Initial parameters were selected to simulate populations of sea urchins and include northern and southern populations of the temperate sea urchin Strongylocentrotus purpuratus and tropical species such as Diadema antillarum. Results of the analysis are intuitively reasonable. Regardless of whether a population is increasing or decreasing, there would always be an increase in fitness associated with increases of: 1) the growth-rate constant, 2) maximum gonad size, 3) maximum lifespan, 4) the shape parameter of the Weibull function; and, decreases of 1) the age at first reproduction and 2) the ratio of number of recruits/spawn weight. If trade-offs are possible then improved survival characteristics and increased lifespan would be favored in declining populations. In general, relative sensitivity is dependent upon which parameter is varied in the simulations. The analysis shows which changes of parameters would bring about the greatest change in fitness but can not show trade-offs or design constraints. An example of trade-off in urchin life history is the relationship between the growth-rate constant, K and maximum lifespan, ω. A doubling of lifespan is associated with a halving of K.

A method is presented for estimating rates of individual growth and population mortality utilizing average individual size at two times during a year. The model assumes a constant rate of mortality, Brody-Bertalanffy growth, a stationary age distribution, and recruitment confined to one month each year. A hypothetical example is presented to show the interrelationships of the growth and mortality constants, size at recruitment, asymptotic size and average individual size. Three examples are presented using data from the literature: Flathead sole (Hippoglossoides elassodon), a sea urchin(Echinus esculentus), and the crown-of-thorns starfish(Acanthaster planci). The method appears to be a means of obtaining reasonable approximations of growth and mortality rates for a variety of organisms.

Purple sea urchins were tagged, measured, and placed in a tidepool at Sunset Bay, Oregon. After 1 year, many animals had decreased in size. Accordingly, size is not necessarily a reliable index of age in Strongylocentrotus purpuratus; however, it is possible to conclude that these animals are relatively long-lived.