Glycaspis Brimblecombei Moore Research Articles

Modeling Environmental Influences in the Psyllaephagus bliteus (Hymenoptera: Encyrtidae)-Glycaspis brimblecombei (Hemiptera: Aphalaridae) Parasitoid-Host System.

Glycaspis brimblecombei Moore (Hemiptera: Aphalaridae) is an invasive psyllid introduced into the Mediterranean area, where it affects several species of Eucalyptus. Psyllaephagus bliteus Riek (Hymenoptera: Encyrtidae) is a specialized parasitoid of this psyllid that was accidentally introduced into Italy in 2011. We developed a model of this host-parasitoid system that accounts for the influence of environmental conditions on the G. brimblecombei population dynamics and P. bliteus parasitism rates in the natural ecosystem. The Lotka-Volterra-based model predicts non-constant host growth and parasitoid mortality rates in association with variation in environmental conditions. The model was tested by analyzing sampling data collected in Naples in 2011 (before the parasitoid was present) and defining several environmental patterns, termed Temperature-Rain or T-R patterns, which correspond to the host growth rate. A mean value of the host growth rate was assigned to each T-R pattern, as well as a variation of the parasitoid mortality rate based on temperature thresholds. The proposed model was applied in simulation tests related to T-R patterns carried out with a data series sampled between June 2014 and July 2015 in five Italian sites located in Campania, Lazio, Sicily, and Sardinia regions. The simulation results showed that the proposed model provides an accurate approximation of population trends, although oscillation details may not be apparent. Results predict a 64% reduction in G. brimblecombei population density owing to P. bliteus parasitoid activity. Our results are discussed with respect to features of the host-parasitoid interaction that could be exploited in future biological control programs.

First record of two invasive eucalypt psyllids (Hemiptera: Psylloidea) in Israel

Two eucalypt-feeding psyllids (Hemiptera: Psylloidea: Aphalaridae): the eucalypt shoot psyllid, Blastopsylla occidentalis Taylor and the red gum lerp psyllid, Glycaspis brimblecombei Moore are reported from Israel for the first time. Both species belong to Spondyliaspidinae, a subfamily of jumping plant lice that feed generally on Myrtaceae, mainly eucalypts. The psyllids were collected from Eucalyptus camaldulensis Dehnh., a dominant eucalypt species in Israel. A summary ofthe globaldistributionand the host trees of the two psyllids are provided and their potential threat to eucalypts in Israel is discussed. Diagnostic information to distinguish between the two psyllids is presented, with an identification key for the adults of six eucalypt-feeding psyllid species in the Western Palearc- tic region.

First record of Glycaspis brimblecombei Moore (Hemiptera: Aphalaridae), in Turkey

In this study, the occurrence of Glycaspis brimblecombei Moore (Hemiptera: Aphalaridae) was recorded for the first time on Eucalyptus camaldulensis (Myrtaceae) leaves in Turkey. In addition the generalist predator Anthocoris nemoralis Fabricius (Hemiptera: Anthocoridae) and the parasitoid of the red gum lerp psyllid Psyllaephagus bliteus Riek (Hymenoptera: Encyrtidae) were also found as natural enemies. P. bliteus is also for the first time recorded in Turkey.

Glycaspis brimblecombei Moore, 1964 (Hemiptera: Psyllidae) on eucalyptus: oviposition non-preference and antibiosis

Forest plantations with Eucalyptus spp. (L’ Her) in Brazil are highly yielding. However, this activity is more and more threatened due to interactions with phytophagous insects, especially by exotic species, such as the red gum lerp psyllid Glycaspis brimblecombei Moore (Hemiptera: Psyllidae). This study aimed to evaluate the resistance in eucalyptus against the psyllid in oviposition and biological development assays, attempting to identify potential genotypes resistant to the pest for forest plantations. In addition, we tested the hypothesis of that concentration of total phenolics and lignin, and amount of epicuticular wax were associated with the expression of resistance. Results showed that there was variation in the levels of resistance among the genotypes assessed. Oviposition non-preference was observed on Eucalyptus citriodora (Hook) in free-choice and no-choice tests, and Clone FP10 was least preferred in the no-choice test. The genotypes E. citriodora and Clone FP6 provided 100 % nymphal mortality, and Clones FP7 and FP9 also affected negatively the G. brimblecombei development by lengthening the duration of the nymphal stage and reducing adult emergence. Clone FP6 had higher concentration of total phenolics and larger contact angle formed between the water droplet and leaf surface, which may be associated with thicker layer of epicuticular wax on the leaves, and one of the causes of high nymphal mortality. Thus, the use of the resistant genotypes of eucalyptus screened against G. brimblecombei is a promising and viable alternative for forest plantations infested with this pest.

First record of the red gum lerp psyllid, Glycaspis brimblecombei Moore (Hemiptera Psyllidae), in Tunisia

During a survey carried out in August 2013 along all coastal areas of north-eastern Tunisia (governorships of Bizerte, Ariana, Tunis, Ben Arous, Nabeul, Sousse), eucalyptus trees were found to be highly infested by the invasive pest Glycaspis brimblecombei Moore, 1964, also known as red gum lerp psyllid. This insect, native to the Australian region and secondarily dispersed also in the Americas, Mauritius, Madagascar and South Africa, very recently started to invade the Mediterranean region and in almost 5 years has spread to the Iberian Peninsula, Italy, Greece and Morocco. Its presence in Tunisia (which is recorded here for the first time) most probably dates back to summer 2012, since typical necrotic spots caused by the lerp of the psyllid had already been noted on leaves during spring 2013. No presence of its main parasitoid – Psyllaephagus bliteus Riek – nor of any other natural enemy, was noted up to now during our survey in Tunisia.

Note on Glycaspis brimblecombei Moore (Hemiptera Psyllidae): A new pest of Eucalyptus in Greece

Leaves of eucalyptus infested by Glycaspis brim-blecombei Moore were found on river red gum (E. camaldulensis) and blue gum (E. globulus) trees in Attiki and Chania region, Greece. The psyllid is recorded for the first time in Greece. Brief information about this psyllid is provided.

First Record of the Australian Psyllid Blastopsylla Occidentalis Taylor (Hemiptera, Psylloidea) from Uruguay

The Australian psyllid, Blastopsylla occidentalis Taylor (Hemiptera, Aphalaridae) is here recorded in Eucalyptus tree plantations in Uruguay. It was first detected in 2010, but may have remained undetected for at least the five preceding years. This is the first record of this species in Uruguay, together with a new host record on Eucalyptus maidenii Muell. It is the fourth species of Australian psylloids, behind Ctenarytaina spatulata Taylor (first detected in 1994), C. eucalypti (Maskell) (in 1998), and Glycaspis brimblecombei Moore (in 2006) to become naturalised in Uruguay. Extralimital distribution and host data are summarised. No economic damage was associated with this species in the field.

Seasonal occurrence and adaptation of the exotic Glycaspis brimblecombei Moore (Hemiptera: Aphalaridae) in Italy

Alien insects usually adapt their phenology and their needs to the environment into which they are introduced. During 2010, the red gum lerp psyllid, Glycaspis brimblecombei, was accidentally introduced into Italy, becoming an invasive pest of Eucalyptus L’Hér. Eucalypts are very common in Italy as ornamental and forest species. The seasonal adaptation of the psyllid was studied at three field sites. G. brimblecombei showed a seasonal population dynamic, suggesting that many generations occur during the year and the species overwinters in all stages without diapause. The population size in the new area of colonization is affected by low winter temperatures, but also by high temperatures in the absence of rainfall. In Lazio, the specific parasitoid Psyllaephagus bliteus was collected for the first time.

New alien insect pests to Portugal on urban ornamental plants and additional data on recently introduced species

SummaryThe spread of invasive pests is an important topic in pest control and early detection is crucial for containment of invasive aliens. In this study the results of recent surveys on alien insects of ornamental urban plants in Portugal are reported. Overall, 13 alien species associated with allochthonous ornamental plants were recorded. Seven of these pests are new to the Portuguese fauna: Tinocallis kahawaluokalani (Kirkaldy); Illinoia liriodendri (Monell); Appendiseta robiniae (Gillette) (Hemiptera: Aphididae); Acizzia jamatonica (Kuwayama) (Hemiptera: Psyllidae); Dasineura gleditchiae (Osten Sacken); Obolodiplosis robiniae (Haldeman) (Diptera: Cecidomyiidae); and Phytoliriomyza jacarandae Steyskal & Spencer (Diptera: Agromyzidae). Additional distribution data are also provided for other recently introduced alien pests in Portugal: Myzocallis (Lineomyzocallis) walshii (Monell) (Hemiptera: Aphididae); Platycorypha nigrivirga Burckhardt; Glycaspis brimblecombei Moore (Hemiptera: Psyllidae); Calophya schini Tuthill (Hemiptera: Calophyidae); Corythucha ciliata (Say) (Hemiptera: Tingidae); and Lantanophaga pusillidactylus (Walker) (Lepidoptera: Pterophoridae). Three species in particular (Illinoia liriodendri, Obolodiplosis robiniae and Phytoliriomyza jacarandae) were not previously found in the Iberian Peninsula. Details on current distribution, host plants and biological remarks are given for each species. Possible origin areas, pathways and impacts are also discussed.

First record of the red gum lerp psyllid Glycaspis brimblecombei Moore (Hemiptera: Psyllidae) in Tuscany (Italy)

The invasive Australian pest Glycaspis brimblecombei Moore, the red gum lerp psyllid, is recorded for the first time in Tuscany (Italy). Its occurrence in this new region, just 2 years after its first record in Italy, shows how rapidly its population has found suitable environmental conditions in Italian territories.

Predicting the geographical distribution ofGlycaspis brimblecombei(Hemiptera: Psylloidea) in Brazil

The red gum lerp psyllid, Glycaspis brimblecombei Moore, has been introduced from Australia into several countries, mostly in the Americas and Europe. It was first discovered in Brazil in 2003 and has continued to spread there. Today, the species is a major pest in eucalypt plantations and often requires expensive control measures. Ecological modelling is used here to estimate the potential spread of G. brimblecombeii, worldwide and particularly in Brazil, based on environmental variables from 502 records of G. brimblecombei around the world. Distribution data from Australia were obtained from the literature and recent field surveys. For the first time, G. brimblecombei is recorded from Western Australia. Through the Openmodeller® program interface, 22 bioclimatic variables were used to test the efficacy of the following models: BIOCLIM, Climate Space Model, Envelope Score, Environmental Distance, GARP with best subsets (new Openmodeller implementation), GARP new Openmodeller implementation, GARP best subsets (Desktop GARP implementation), Niche Mosaic and Support Vector Machines. Among these models, Environmental Distance was the best predictor for the potential distribution of G. brimblecombei in new regions. Temperate areas appeared to be more favourable for G. brimblecombei. Regions with highest probability of occurrence in Brazil, in hierarchical order are: the southern part of the Atlantic Forest, Pampa, Caatinga and Cerrado. This modelling procedure provides a useful tool that should be incorporated in future strategies for pest management in eucalypt plantations.

Climate and the effectiveness of Psyllaephagus bliteus as a parasitoid of the red gum lerp psyllid

The encyrtid parasitoid Psyllaephagus bliteus Riek was introduced to California in 2000 to control the red gum lerp psyllid, Glycaspis brimblecombei Moore. Field experiments were conducted to determine the effect of regional summer climate (California coastal vs. interior valleys) on P. bliteus performance. Measurements of parasitoid performance, including reproduction and longevity, showed that P. bliteus was adversely affected by the extreme summer heat in the interior valley sites. The results suggest that regional climatic differences can contribute to the lower parasitism rates observed in California's warmer interior valleys. The results are discussed with respect to biological control of G. brimblecombei and the potential limitations of the parasitoid P. bliteus, as well as the possible impact of climate and intraguild predation as alternative hypotheses for the observed variable geographic performance of P. bliteus.

Attractiveness and oviposition preference of Glycaspis brimblecombei Moore in Eucalyptus spp.

The red gum lerp psyllid Glycaspis brimblecombei Moore (Hemiptera: Psyllidae) was first recorded in Brazil in 2003 and since then has caused serious damage in Eucalyptus forests. The damage is mainly due to defoliation, sooty mold and dieback, thus requiring the development of efficient management strategies. The settling and ovipositional preference of G. brimblecombei by species and clones of Eucalyptus were evaluated in free- and no-choice tests. Preliminary tests were done to determine the density of psyllid couples that produced the greatest densities of eggs, leaf position selection for oviposition, and whether oviposition was affected by preimaginal conditioning. Apical leaves were used more frequently for oviposition by the psyllid, and the number of eggs decreased from the apex to the base. The densities of 10 and 15 psyllid couples per seedling produced the highest oviposition. There was no evidence of preimaginal conditioning. In the free-choice test, E. grandis, E. urophylla, VM-1, I-144, C-219 and H-13 were less attractive to G. brimblecombei adults, with H-13, E. grandis and E. urophylla having the least oviposition. In the no-choice test, E. urophylla, GG-100 and E. grandis also demonstrated a lower oviposition, but E. camaldulensis and 3025 were highly susceptible. The low preference for the genotypes E. grandis and E. urophylla suggests the occurrence of a non-preference type resistance against the red gum lerp psyllid. Our results can be utilized for the development of management programs for G. brimblecombei in Eucalyptus forests.

Associations between invasive eucalyptus psyllids and arthropod litter communities under tree canopies in southern California

AbstractHoneydew‐producing psyllids are an important pest of eucalyptus (Myrtaceae) in California, USA, and may influence surrounding litter arthropod communities. In particular, the introduced Australian psyllids Glycaspis brimblecombei Moore and Eucalyptolyma maideni Froggatt (both Hemiptera: Psyllidae) may facilitate the prevalence of invasive ant species. We examined ground‐dwelling arthropod communities under eucalyptus trees infested by psyllids. We used a model comparison approach to examine the association of psyllid infestation, ant abundance, and environmental factors with ground arthropod abundance and richness. We found a significant positive association between ant activity on eucalyptus trees and psyllid abundance. Higher psyllid abundance and higher Argentine ant abundance were associated with increased arthropod richness. Irrigation was also associated with increased arthropod richness and abundance. Regardless of location collected, arthropod communities collected in pitfall traps under trees with high psyllid abundance had high similarity to arthropod communities under trees with high ant activity. Abundance of isopods was positively associated with both ant and psyllid abundance. Other arthropod groups differed in their association with ants and psyllids. Argentine ants may exacerbate pest impacts and may also decrease the effectiveness of biological control programs for eucalyptus lerp psyllids.

An experimental test of rainfall as a control agent of Glycaspis brimblecombei Moore (Hemiptera, Psyllidae) on seedlings of Eucalyptus camaldulensis Dehn (Myrtaceae)

An experimental test of rainfall as a control agent of Glycaspis brimblecombei Moore (Hemiptera, Psyllidae) on seedlings of Eucalyptus camaldulensis Dehn (Myrtaceae). Glycaspis brimblecombei is one the greatest threats to eucalyptus plantations in Brazil. The effects of rainfall to reduce the abundance of lerp of Glycaspis brimblecombei on experimentally infested seedlings of Eucalyptus camaldulensis were assessed. The number of lerps on the adaxial and abaxial surfaces of every of 60 seedlings was recorded, before and after submission to the following treatments: rain, leaf wetting and control. A drastic reduction in lerp abundance per plant was observed after the treatments leaf wetting and artificial (F = 53.630; p < 0.001), whereas lerp abundance remained roughly constant in the control treatment along the experiment (F = 1.450; p = 0.232). At the end of the experiment, lerp abundance was significantly lower in both the rain and leaf wetting than in the control treatment. Two days of rainfall simulation were sufficient to decrease more than 50% of the lerp population, with almost 100% of effectiveness after 5 days of experiment. Our results indicate that lerp solubilization and mechanical removal by water are potential tools to the population regulation of G. brimblecombei on E. camaldulensis seedlings.

Eco-éthologie des nouveaux ravageurs invasifs des eucalyptus du Maroc

Résumé Trois nouveaux ravageurs invasifs ont été observés au cours de cette dernière décennie dans les peuplements d’eucalyptus de la région du Gharb au Maroc. Un premier gallicole, Leptocybe invasa Fisher & La Salle 2004 (Hymenoptera: Eulophidae), a été repéré dès 2002, tandis que son parasitoïde Megastigmus sp. (Chalcidoidea: Torymidae) a été identifié en 2009. Les deux autres ravageurs, Ctenarytaina eucalypti (Maskell 1890) et Glycaspis brimblecombei Moore 1964 (Hemiptera: Psyllidae), ont été découverts respectivement en 2008 et 2009. Quelques paramètres bio-écologiques relatifs au développement de L. invasa ont été mesurés au laboratoire et sur le terrain, tandis que le taux d’infestation de jeunes eucalyptus a été suivi pendant trois années successives. Les stratégies de lutte envisagées contre ces nouveaux ravageurs sont discutées.

Establishment of the red gum psyllid parasitoid

The red gum lerp psyllid, Glycaspis brimblecombei Moore (Hemiptera: Psyllidae), was detected in Eucalyptus sp. foliage in Santiago, Chile, in 2002. The successful biological control results obtained in the US and Mexico using Psyllaephagus bliteus Riek (Hymenoptera: Encyrtidae) prompted its use in Chile. After its introduction during 2003, it became established in two years. To assess its effectiveness on G. brimblecombei, the level of parasitism by P. bliteus was determined in four sampling sites in Santiago, where random samples of 50 lerps (carbohydrates and protein shelters) were collected per site on trees infested with the psyllid every other week, during a 4 month period in the spring-summer of 2008-2009. Also, natural enemies were sampled with sticky traps on ten trees at two sites, which were evaluated every 15 days. Results were compared with a previous evaluation. The density of nymphs of the psyllid was ostensibly reduced by the action of P. bliteus throughout the season. The biological control program of G. brimblecombei with P. bliteus is developing well when comparing results with the previous evaluation in 2005 in Santiago, with a significant increase in the rate of parasitism. Generalist predators had also interacting with P. bliteus and G. brimblecombei. These results indicate a promising use of this parasitoid to strengthen the integrated management of the red gum lerp psyllid in the central zone of Chile.

Establishment of the red gum psyllid parasitoid

The red gum lerp psyllid, Glycaspis brimblecombei Moore (Hemiptera: Psyllidae), was detected in Eucalyptus sp. foliage in Santiago, Chile, in 2002. The successful biological control results obtained in the US and México using Psyllaephagus bliteus Riek (Hymenoptera: Encyrtidae) prompted its use in Chile. After its introduction during 2003, it became established in two years. To assess its effectiveness on G. brimblecombei, the level of parasitism by P. bliteus was determined in four sampling sites in Santiago, where random samples of 50 lerps (carbohydrates and protein shelters) were collected per site on trees infested with the psyllid every other week, during a 4 month period in the spring-summer of 2008-2009. Also, natural enemies were sampled with sticky traps on ten trees at two sites, which were evaluated every 15 days. Results were compared with a previous evaluation. The density of nymphs of the psyllid was ostensibly reduced by the action of P. bliteus throughout the season. The biological control program of G. brimblecombei with P. bliteus is developing well when comparing results with the previous evaluation in 2005 in Santiago, with a significant increase in the rate of parasitism. Generalist predators had also interacting with P. bliteus and G. brimblecombei. These results indicate a promising use of this parasitoid to strengthen the integrated management of the red gum lerp psyllid in the central zone of Chile.

Control of red-gum lerp psyllid with formulated mycoinsecticides under semi-field conditions

This study evaluated the potential use of commercial mycoinsecticide formulations against red-gum lerp psyllid Glycaspis brimblecombei Moore in semi-field conditions. Eucalypt seedlings infested with psyllid nymphs were sprayed with different formulations and two concentrations of each product. Conidial deposits were evaluated after spraying for control efficiency. The conidial deposit was affected by the pathogen species and by formulation types. Higher conidial deposits were associated with mycoinsecticide formulation concentrates of lower granulometry and oil dispersion. However, some products with low deposits of conidia were highly efficient against psyllid nymphs. The results showed that the use of entomopathogenic fungi is a promising alternative method for controlling the red-gum lerp psyllid.

Glycaspis brimblecombei (Hem.: Psyllidae), la psilla dal follicolo bianco ceroso, altra specie aliena dell’Eucalipto rosso in Italia

During 2010 in central and southern Italy (Campania, Basilicata and Latium), the invasive red gum lerp psyllid, Glycaspis brimblecombei Moore (Hemiptera: Psyllidae), has been recorder for the first time in Italy. The psyllid was detected on Eucalyptus camaldulensis in several sampling sites. The host plant, like other species of the genus Eucalyptus, is very common in Italy as ornamental and forest species. The native country of G. brimblecombei is Australia, from which the psyllid spread throughout the world in the last decade. In the Palaearctic Region the species was first collected from the Iberian Peninsula in 2007. In this note we report some observations on the biology and distribution of this species in the new colonized Italian areas. Generalist predators, such as wasps and pirate bugs, were observed attacking G. brimblecombei, however no parasitoid activity has been detected.