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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]

Austropuccinia psidii, cause of myrtle rust, has spread globally where Myrtaceae occur. Multiple strains of A. psidii have been identified, including a unique strain found only in South Africa. The South African strain is a biosecurity concern for species of Myrtaceae worldwide. This is because preliminary testing of South African Myrtaceae suggests it could have a wide host range, and thus has the potential to be invasive. In this study, we assessed the ability of the South African strain to infect other species of Myrtaceae by testing the susceptibility of New Zealand provenance Myrtaceae. Seedlings of four native New Zealand Myrtaceae species (Metrosideros excelsa, Leptospermum scoparium, Kunzea robusta, and Kunzea linearis) were artificially inoculated in South Africa with a single‐uredinium isolate of the South African strain. Fourteen days after inoculation, uredinia, and in many cases telia, had developed on the young leaves and stems of all four host species, which led to shoot tip dieback in the more severe cases. When comparisons were made between the species, K. robusta was the least susceptible to the South African strain of A. psidii, while L. scoparium and M. excelsa were the most susceptible. While only a limited number of seed families were tested, only a small proportion of the seedlings showed resistance to infection by the South African strain. This preliminary testing highlights the potential invasive risk the South African strain poses to global Myrtaceae communities, including New Zealand Myrtaceae. [ABSTRACT FROM AUTHOR]

Plantations of Pinus spp. in Colombia are severely damaged by various phasmid (Phasmatodea: Diapheromeridae) insects. Of these, Litosermyle ocanae is one of the most serious defoliators. Since 1988, several outbreaks have been recorded in Pinus patula plantations, resulting in substantial economic losses. The aim of this study was to determine the life cycle of Litosermyle ocanae in P. patula plantations in Colombia. In addition, we assessed the population levels of L. ocanae and the presence of natural enemies of L. ocanae in these plantations. The development of L. ocanae was monitored under controlled conditions, and population fluctuations and the presence of natural enemies was assessed from field-collected eggs and field observations. The results showed a total life cycle of 225 d and 235 d for males and females, respectively, and a complete fourth instar nymph cycle of 121 d and 116 d for males and females, respectively. The sex ratio was 1:1.7 female to male. Females laid an average of 112 eggs. The number of eggs peaked in November and the most dominant natural enemy observed was a parasitoid wasp Adelphe sp. (Hymenoptera: Chrysididae). The results provide important information for the management of L. ocanae in P. patula plantations. [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]

Subsequent to 1950, commercially propagated and non-native trees, includingPinus, EucalyptusandCupressusspecies in Colombian plantations, have been damaged by several native defoliating insects, residing mainly in the Lepidoptera (Geometridae), Phasmatodea (Heteronemiidae) and the Hymenoptera (Formicidae). We report on the relatively recent appearance of three important and damaging new insect pests of plantation-grownPinusandEucalyptusspp. in Colombia, two of which are not native to this country. These includeMonalonion velezangeli(Hemiptera: Miridae),Glycaspis brimblecombei(Hemiptera: Psyllidae) andPineus boerneri(Hemiptera: Adelgidae). This report provides information on the basic biology of these new pests, their hosts, areas of occurrence, likely origin and prospects for their management in the future. [ABSTRACT FROM AUTHOR]