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Austropuccinia psidii, the causal agent of myrtle rust, has emerged as a significant threat to Myrtaceae in planted and natural woody ecosystems. The first detection of A. puccinia in South Africa was from severely infected ornamental Myrtus communis. This raised concern that M. communis, the sole Myrtaceae species native to Europe and an important component of vegetation in Mediterranean regions, could be threatened by the rust. In light of the potential threat to this unique species, seed was collected from 12 Italian provenances of M. communis, including mainland and island (Sardinia and Sicily) populations. We assessed the susceptibility of these provenances to both the pandemic and South African strains of A. psidii. In Colombia, where the pandemic strain of A. psidii is native, seedlings rapidly became infected by natural inoculum. In South Africa, a preliminary screening of seedlings by artificial inoculation with a single-uredinium isolate produced high levels of disease. Finally, plants of each of the 12 provenances were planted and monitored in Florence, Italy. To date, these showed no signs of disease, but will continue to be monitored. This study highlights the significant threat that both the pandemic and South African strains of A. puccinia pose to M. communis in Europe. [ABSTRACT FROM AUTHOR]

Adelgids (Hemiptera) in the genusPineushave been reported as introduced insect pests causing serious losses toPinusplantations worldwide. In 2008,Pineus boerneriwas recorded for the first time in Colombia, with infestations noted onPinus kesiya,P. tecunumanii,P. maximinoiandP. oocarpa. The lack of information on this insect in Colombia prompted investigations of its life cycle and infestation levels as well as host susceptibility of the mainPinusspecies planted in Colombia. In addition, the possibility of using aCeraeochrysaspecies, an already established predator of adelgids in Colombia, for biological control was considered. Results showed thatPineus boerneriin Colombia has an anholocyclic life cycle comprised of four instars with a complete duration of between 49 and 97 d. Infestations were higher in the middle and upper part of trees.Pinus kesiyaandP. maximinoihad the highest levels of susceptibility in field as well as in greenhouse trials. A survey of naturally infested trees showedP. tecunumaniito be moderately susceptible, whereasP. patulaandP. oocarpahad low levels of susceptibility in a greenhouse trial but were not susceptible in the field. Investigations considering the impact of predation ofCeraeochrysaspecies showed a high predation rate of up to 140P. boernericonsumed per day by a singleCeraeochrysaindividual. Other predators ofP. boerneriwere recorded but were not sufficiently common to warrant detailed study. [ABSTRACT FROM AUTHOR]