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Insect predators are the most important natural enemies of the crapemyrtle bark scale (CMBS) in the USA. Mycopesticides (biocontrol fungi) are considered an IPM tool to increase CMBS mortality; however, their impacts on CMBS predators are unknown. The objectives of this study were to assess the abundance and diversity of CMBS natural enemies in Louisiana; evaluate the impacts of mycopesticides on survival of CMBS predators by life stage; and determine if entomopathogenic spores delivered to crapemyrtles are transferred to predators under field conditions. The mycopesticides Ancora® (Isaria fumosorosea PFR97), BioCeres® (Beauveria bassiana ANT-03), and BotaniGard® (B. bassiana GHA) were tested against the coccinellids Chilocorus spp. and Hyperaspis bigeminata under laboratory and field conditions. Adults and larvae of the coccinellids were treated with each mycopesticide and survival recorded over a 14-day period. The most common natural enemies on CMBS infested trees were the coccinellids Chilocorus cacti, C. stigma, and Hyperaspis bigeminata (Coleoptera: Coccinellidae). In laboratory bioassays BotaniGard® reduced survival of adults and larvae of both genera by at least 57%. BioCeres® reduced the survival of Chilocorus spp. adults by 40% and Ancora® reduced survival of H. bigeminata larvae by 69%. Under field conditions, CMBS infestations were sprayed with the mycopesticides and coccinellids were collected every other day for a two-week period. Spores of the applied mycopesticides were recovered from the coccinellids; however, it is not known if infection occurred in the field trial or spores were delivered to CMBS infestations by the coccinellids. We conclude that mycopesticides negatively impacted the survival of coccinellids in laboratory trials, and coccinellids can transport pathogen spores under field conditions., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Physiological limits of non-native species to environmental factors are critical for their establishment and spread in the adventive range. The crapemyrtle bark scale, Acanthococcus lagerstroemiae (Kuwana), is a major pest of crapemyrtles. Despite concerns on its rapid spread, there is a lack of information on potential distribution range of this scale in the United States. To understand this scale's distribution potential, its thermal tolerance was evaluated using higher and lower thermal limits. Exposure time leading to 50 and 90% mortality (Lt50 and Lt90) at extreme low or high temperatures were measured under controlled conditions. A model was then built to fit temperature data of cold fronts from 2001 to 2016 and to calculate potential mortalities along latitudes. Isothermal lines delineated at 90% mortality were defined as the northern limits. Modeling results suggested that A. lagerstroemiae nymphs collected in summer could tolerate heat; however, they were more susceptible to cold temperatures. Laboratory assays suggested that cold tolerance of A. lagerstroemiae nymphs varied from summer to winter. For example, SCP of nymphs collected in summer was higher than those collected in fall (-21 vs. -27°C), and the exposure time leading to Lt90 at 0°C was also different, which were 8 versus 50 h comparing nymphs collected in summer versus fall. Our prediction suggested that A. lagerstroemiae is likely to be limited by cold temperatures along the 43° N latitude. Based on these results, integrated management strategies can be developed for A. lagerstroemiae within the predicted range., (© The Author(s) 2019. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Temperature is one of the most important abiotic factors influencing the adaptation and diversification of insects. Diverse and complex physiological mechanisms have evolved to help insects adapt to seasonal changes in temperature and prevent cold injury. Although the mechanisms of seasonal adaptation to low temperatures have been studied for insects in different taxa, none of these mechanisms have been investigated in scale insects in the superfamily Coccoidea. The crapemyrtle bark scale, Acanthococcus lagerstroemiae (Kuwana) (Hemiptera: Eriococcidae), is a newly introduced scale pest of crapemyrtles, Lagerstroemia spp. (Myrtales: Lythraceae). Our previous study concerning the cold tolerance of this pest suggested that, from summer to winter, A. lagerstroemiae seasonally adapted to lower temperature with a 5 °C reduction of supercooling points. In addition, time required to achieve the same levels of mortality at lower temperatures also increased. In this study, we used A. lagerstroemiae as a model system to investigate the physiological mechanisms correlated with changes in cold tolerance in scale insects, by measuring water content, lipid content and fatty acid composition, and cryoprotective polyols and sugars every other month. Results suggested that water content was lower in winter and early spring than in summer and early fall (40.8% vs. 63.3%). The proportions of the fatty acids in PL were similar over seasons, but in TAG, shorter chain fatty acids (from C6:0 to C10:0) increased in winter as longer chain fatty acids (from C14:0 to C18:0) decreased. Among all measured polyols and sugars, including glycerol, d-mannitol, myo-inositol, and d-trehalose, the levels of d-mannitol were the highest in January 2016, which were 19-times of those in March 2016 and 4.5-times of those in September 2016. Results from this study provide a better understanding on how A. lagerstroemiae overwinters, which may give insights into the overwintering strategies of other scale insects., (Copyright © 2018. Published by Elsevier Ltd.)

Bacteria associated with sap-feeding insect herbivores include not only symbionts that may increase their hosts' fitness but also harmful plant pathogens. Calophya spp. gall-inducing psyllids (Hemiptera: Calophyidae) are being investigated for their potential as biological control agents of the noxious weed, Brazilian peppertree (Schinus terebinthifolia), in Florida. Although there are no examples of plant pathogen transmission by members of the family Calophyidae, several insects in the superfamily Psylloidea are known to transmit pathogenic bacteria in the genera Candidatus Liberibacter and Candidatus Phytoplasma. To determine whether Calophya spp. harbor potentially harmful plant pathogenic bacteria, we sequenced small subunit (SSU) ribosomal RNA (rRNA) gene amplicons generated from individuals from four Calophya spp. populations: All microbial SSU gene sequences fell into the bacterial domain, with 98-99% belonging to the Proteobacteria. The Calophya microbiomes contained a relatively simple community, with 49-79 operational taxonomic units (OTUs; 97%) detected, and only 5-8 OTUs with greater than 1% abundance. Candidatus Carsonella showed the highest relative abundance, with OTUs from this candidate genus representing between 51-65% of all recovered sequences. The next most abundant clade observed was an unclassified Enterobacteriacae group closely related to bacteria from the genera Buchnera and Blochmannia that ranged from 20-31% in relative abundance. Wolbachia populations were the third most abundant group and represented 7-27% of the diversity in microbial OTUs. No SSU rRNA gene sequences from putative pathogenic bacteria from the genera Ca. Liberibacter or Ca. Phytoplasma were detected in the microbiomes of the four Calophya populations. The probability that infected psyllids were present in our colonies, but were not sampled, was extremley low (1.39 x 10(-10)). As far as we are aware, our study is the first to characterize the microbiome of a candidate biological control agent, and coupled with previous work demonstrating a high degree of host specificity and absence of plant viruses, suggests that releasing Calophya spp. in United States poses minimal risk to non-target plants.

Schinus terebinthifoliaRaddi (Anacardiaceae) (Brazilian peppertree) is one of the most serious terrestrial invasive plants in Florida. The leaf galling psyllid,Calophya latiforcepsBurckhardt (Hemiptera: Calophyidae), was discovered feeding on the Brazilian peppertree in Bahia, Brazil, in 2010, and is being evaluated for release as a biological control agent. In order to understand how this candidate biological control agent affects the growth ofS. terebinthifolia, we measured the effect of the psyllid on photosynthesis, leaf chlorophyll content and plant growth. Infested plants had lower photosynthesis compared to uninfested plants 30 and 45 days after gall initiation, and chlorophyll content was lower over a 70-d period. Plant height was reduced 31% and biomass 11% after three months of infestation. Results of these studies suggest thatC. latiforcepswill negatively affect the growth of the Brazilian peppertree if released in Florida. [ABSTRACT FROM AUTHOR]

Brazilian peppertree, Schinus terebinthifolia Raddi ( Anacardiaceae), is one of the worst upland exotic weeds in Florida, USA. Foreign exploration for natural enemies led to the discovery of a pit-galling psyllid, Calophya latiforceps Burckhardt ( Hemiptera: Calophyidae), in the state of Bahia, Brazil, in 2010. Crawlers of C. latiforceps stimulate the formation of galls on the leaves of S. terebinthifolia resulting in leaf discoloration and in some cases leaf abscission. To determine whether C. latiforceps is a safe candidate for biological control of S. terebinthifolia, host specificity and the presence of selected plant pathogens were examined. Adult oviposition, gall formation, and adult survival of C. latiforceps were examined on 89 plant species under no-choice and choice conditions. We found that C. latiforceps laid eggs on plants in seven families; however, crawlers stimulated gall formation and completed development to adult only on S. terebinthifolia. All crawlers on non-target plants died, likely due to starvation caused either by the absence of a feeding stimulus or by a hypersensitive plant response. Under no-choice conditions, 10% of adults lived for 19 days on the target weed, but adult survival was reduced to <3 days on non-target plants. Choice testing revealed that females preferred to oviposit on S. terebinthifolia compared to non-target plants. Molecular methods and indicator host inoculations did not detect the presence of ' Candidatus Liberibacter solanacearum', ' Ca. L. asiaticus', ' Ca. L. americanus', ' Ca. L. africanus', or plant viruses in adult C. latiforceps. We conclude that releasing C. latiforceps in the USA will have extremely low risk to non-target plants, and provides another tool for the management of S. terebinthifolia. [ABSTRACT FROM AUTHOR]

Native range and life history studies of an agent provide critical information during the early stages of a weed biological control programme. Brazilian peppertree is considered to be one of the worst invasive trees of Florida uplands because of negative environmental impacts and lack of effective long-term control methods. A potential biological control agent of Brazilian peppertree,Calophya latiforcepsBurckhardt (Hemiptera: Calophyidae), was recently discovered in the state of Bahia, Brazil. Leaf feeding by the nymphs ofC. latiforcepsstimulates the tree to form pit galls. The objectives of this study were to quantify gall densities in Bahia and to study the life history adaptations ofC. latiforcepsunder greenhouse conditions. Densities of galls and their mortality sources were recorded in August 2012 and March 2013 from trees located along linear transects. Gall density per leaf ranged from 1.6 to 37.5 and 0.3 to 12.8, in August and March, respectively. Nymphal mortality due to parasitism and entomopathogens ranged from 1.2 to 13.8%. Greenhouse observations of host colonisation and evaluations of immature survival and adult performance were conducted using plants from Bahia. A critical step for host colonisation was gall initiation in response to nymphal feeding. Herbivory byC. latiforcepsresulted in stunted growth, leaf deformation, yellowing and shedding of leaves. Immature survival and development time were influenced by tree, and ranged from 11 to 75% (average 40%), and 35 to 53 days (average 38.6 days), respectively. Adults lived in average for 9.3 ± 0.6 days; and females laid 85.8 ± 16.4 eggs.C. latiforcepsappears to have characteristics of a promising candidate for biological control of Brazilian peppertree. [ABSTRACT FROM PUBLISHER]

Abstract: Life history parameters of the sap-feeding bug Ischnodemus variegatus (Signoret) (Hemiptera: Blissidae) were compared between the invasive Neotropical grass, Hymenachne amplexicaulis (Rudge) Nees and the Australian native Hymenachne acutigluma (Steudel) Guilliland. Development of immatures, adult longevity, ovipositional preference and population growth of I. variegatus were compared on H. amplexicaulis and H. acutigluma under choice and no-choice conditions. Third-instar nymphs developed on both hosts but individuals reared on H. acutigluma had a 40% lower survival rate to the adult stage, 40% longer developmental time, a 9% reduction in length and a 30% reduction in weight of females compared to those reared on H. amplexicaulis. The no-choice adult longevity and oviposition study indicated that individuals feeding on H. acutigluma had half the lifespan, 62% as many ovipositing females, 52% longer time to first oviposition and only 14% as many eggs per female. Under choice conditions, females laid only 37% as many eggs on H. acutigluma as on H. amplexicaulis. Population growth of I. variegatus was slower on H. acutigluma compared to H. amplexicaulis over a 60day period resulting in negative population increase on H. acutigluma but positive increase on H. amplexicaulis. These results reflect an overall poorer performance of I. variegatus on H. acutigluma for most life stages. [ABSTRACT FROM AUTHOR]

The article reports on the study which examines the temperature-dependent development of cycad aulacaspis scale, Aulacaspis yasumatsui Takagi (hemiptera). The study notes that the lowest temperature which ranges from 8 to 12 degrees celcius and 538 degree-days are needed for female immature development in a linear model. The development rates of the scale of cycad aulacaspis scale, Aulacaspis yasumatsui Takagi and their natural enemies including Rhyzobius lophanthae are also presented.

Four populations of Calophya spp. (Hemiptera: Calophyidae) collected in Brazil were characterized using molecular and morphological methods. Examination of adults revealed the presence of 2 morphotypes, which were identified as C. latiforceps and C. terebinthifolii. However, morphological examination of 5th instar nymphs detected differences within C. latiforceps, with a population from Ubu, Espírito Santo, being distinct from the other 2 populations. Molecular characterization of the mitochondrial CO1 gene supported the presence of a new species of Calophya. [ABSTRACT FROM AUTHOR]

The crapemyrtle bark scale, Acanthococcus lagerstroemiae (Kuwana) (Hemiptera: Eriococcidae), is an invasive pest of crapemyrtles, Lagerstroemia spp. L. (Lythraceae) in the southeastern USA. Information about its temperature-dependent development and host range is limited. The objectives of this study were to evaluate the effects of temperature on the immature development of A. lagerstroemiae, and to determine plant species suitable for immature development and reproduction. Developmental time and survival of eggs were evaluated at 7 constant temperatures from 17.5 to 32 °C, and of nymphs at 20, 25, and 30 °C. Results suggested that 27.5 °C was the optimum temperature for egg hatching with the shortest time (10 d) and the highest hatching rate (95%). The developmental time for A. lagerstroemiae from nymph to prepupa and gravid female was 56 d and 68 d at 30 °C, respectively. Five plant species besides crapemyrtle (Lagerstroemia indica × fauriei L.) were able to support the immature development and reproduction of A. lagerstroemiae under no-choice conditions, including Lawsonia inermis L., Heimia salicifolia Link, Punica granatum L., Lythrum alatum Pursh (all Lythraceae), and Callicarpa americana L. (Lamiaceae). At wk 12 from inoculation, the density of gravid females was 482 ± 92 (mean ± standard error) on L. indica × fauriei, 200 ± 70 on C. americana, and < 150 on other species. Using data from developmental time and host range, integrated pest management (IPM) practitioners can implement preventive strategies for A. lagerstroemiae. [ABSTRACT FROM AUTHOR]

Brazilian peppertree, Schinus terebinthifolia Raddi (Anacardaceae), native to Argentina, Brazil, Paraguay, and Uruguay, is one of the most invasive weeds in Florida. In its native range, at least 4 psyllid species of the genus Calophya (Hemiptera: Calophyidae) are associated with it. All 4 species are monophagous and constitute a likely monophyletic group that induce pit galls, usually on the upper leaf surface. Here we revise the taxonomy of these species, 2 of which are described as new, viz. C. lutea sp. nov. and C. praestigiator sp. nov. Morphological differences between the 4 species are detailed and relevant structures are figured. Keys for adults and the fifth instars are provided for the identification of the 8 species known to induce pit galls on Schinus species. [ABSTRACT FROM AUTHOR]

Egg duration period, immature development time, and pre-oviposition period of the cycad aulacaspis scale, Aulacaspis yasumatsui Takagi, were measured at 9 constant temperatures in the laboratory. Egg duration period ranged from 15 d at 20°C to 7 d at 30°C. First instar development time was 30 d at 18°C but only 4 d at 35°C. No first instars completed development below 18°C or above 35°C. Development time of second instar females ranged from 19 d at 18 and 20°C to 9 d at 30°C. Development time of male second instar + pupa ranged from 15 d at 20°C to 9-10 d at 25-32°C. Pre-oviposition period averaged 14 d at 20°C to 8 d at 25- 32°C; no females laid eggs at 18 and 35°C. The lowest temperature threshold for all stages ranged from 8 to 12°C and 538 degree-days were required for female immature development in a linear model. Development rates of the scale are compared to those of 3 of its natural enemies, Cybocephalus nipponicus Endrödy-Younga, Rhyzobius lophanthae (Blaisdell), and Coccobius fulvus (Compere and Annecke). [ABSTRACT FROM AUTHOR]

[Display omitted] • Trials demonstrate that CMBS is susceptible to several fungal biopesticides. • CMBS is more affected by Beauveria bassiana strains than Isaria fumosorosea PFR97. • Biopesticide applications in autumn and winter resulted in higher scale mortality than spring treatments. • Spore germination of all fungal strains was greatest at 28 °C. The crapemyrtle bark scale (CMBS), Acanthococcus lagerstroemiae, is an important pest of crapemyrtles, Lagerstroemia spp. Biopesticides are frequently used to control soft-bodied insects; however, there is no information on their efficacy against CMBS. The objectives of this study were to test the use of selected biopesticides against CMBS under different seasons, evaluate their pathogenicity to CMBS, and determine optimum temperature for spore germination. Commercial formulations of the fungal biopesticides Isaria fumosorosea PFR97, Beauveria bassiana ANT-03, and the bacterial biopesticides Burkholderia rinojensis A396 and Chromobacterium subtsugae PRAA4-1 T were tested in greenhouse settings and did not have significant treatment effect on immature mortality. Biopesticides containing I. fumosorosea PFR97, B. bassiana ANT-03, and B. bassiana GHA were applied to mature crapemyrtles grown in the landscape and naturally infested with CMBS, and the scale survivorship was determined in two trials at different seasons. When treatments were applied in winter, scale survivorship was significantly lower in the B. bassiana ANT-03 treatment compared to the control. When treatments were applied in spring, no treatment effect was observed. During another trial conducted in autumn using container-grown crapemyrtles, B. bassiana GHA treatment reduced scales survivorship when compared to the control. Pathogen re-isolation assays confirmed that scales collected in the spring trial were had all pathogens delivered; in addition, B. bassiana ANT-03 was the most recovered pathogen. In a temperature-dependent spore germination assay, the optimum temperature range for I. fumosorosea PFR97, B. bassiana ANT-03, and B. bassiana GHA was between 22.5 and 30 °C, with peak spore germination observed at 28 °C for all three pathogens. Results from this project suggest that biopesticides containing strains of B. bassiana can be included in the toolbox for CMBS control, provided that climate and product coverage are considered. [ABSTRACT FROM AUTHOR]