Seasonal occurrence and adaptation of the exoticGlycaspis brimblecombeiMoore (Hemiptera: Aphalaridae) in Italy

Abstract

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.

Development of Glycaspis brimblecombeiMoore (Hemiptera: Aphalaridae) on Eucalyptus camaldulensisDehnh. and Eucalyptus dunniiMaiden

“…Similarly, Laudonia et al . (), when studying seasonal occurrence of G. brimblecombei in Italy, showed that rain during summer and after a dry period was favourable for psyllid population increase. The results of the present study do not support, nor do they reject the influence of rainfall in psyllid abundance, presumably because there are no distinct periods of rainfall and drought in the study area.…”

Glycaspis brimblecombei (Hemiptera: Psyllidae) attack patterns on different Eucalyptus genotypes

“…Several studies conducted with G. brimblecombei in other countries indicate that temperature is the main factor involved in population dynamics of this psyllid (Paine, Millar & Hoddle, 2000; Ramirez, Mancera & Guerra-Santos, 2003; Laudonia, Magiotta & Sasso, 2014). Under laboratory conditions in Brazil, Firmino found that 26 °C is the optimal temperature for the development and reproduction of G. brimblecombei .…”

“…Psyllid nymphs produce honeydew after initial feeding and use it with a wax secretion to build tapered protective white shelters (lerp) on the leaf surface (Sharma et al, 2013). G. brimblecombei has five nymph instars, with a complete lifecycle from 15 to 34 days, and several generations per year (Firmino-Winckler et al, 2009; Laudonia, Magiotta & Sasso, 2014). There are no records of diapause for this psyllid species, even during the winter in temperate countries (FAO, 2012; Laudonia, Magiotta & Sasso, 2014).…”

“…G. brimblecombei has five nymph instars, with a complete lifecycle from 15 to 34 days, and several generations per year (Firmino-Winckler et al, 2009; Laudonia, Magiotta & Sasso, 2014). There are no records of diapause for this psyllid species, even during the winter in temperate countries (FAO, 2012; Laudonia, Magiotta & Sasso, 2014). In its original habitat in Australia, G. brimblecombei prefers to feed on E. camaldulensis Dehn (Myrtaceae) and natural enemies, such as parasitoids and predators, exert strong control of psyllid populations (Collett, 2001).…”

Anatomy of an outbreak: the biology and population dynamics of aCardiaspinapsyllid species in an endangered woodland ecosystem

“…The present study aimed to characterize this new Cardiaspina and E. moluccana interaction, and to determine the main biotic and abiotic factors influencing the population dynamics during the peak of this outbreak and any subsequent decline. Temperature is known to have a strong influence on aphid populations (Dixon, ) and has been reported to influence population abundance in psyllids (Laudonia et al ., ). Outbreaks of Cardiaspina species are known to result in severe defoliation of their host plants (Clark, ) as a result of psyllid‐induced leaf senescence (Steinbauer et al ., ).…”