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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]

Eucalyptus spp. are widely planted in Colombia as an important component of a growing paper and pulp industry. Leaf and shoot blight caused by Calonectria spp. was one of the first disease problems to emerge in these plantations. A survey of Eucalyptus plantations in four forestry regions of Colombia during 2016 resulted in a large number of Calonectria isolates from soil samples collected in the understories of trees having symptoms of Calonectria leaf and shoot blight. The aim of this study was to identify and resolve the phylogenetic relationships for these isolates using DNA sequence comparisons of six gene regions as well as morphological characters. From a collection of 107 isolates, seven Calonectria species residing in three species complexes were identified. Two of these represented undescribed species, namely C. exiguispora sp. nov. and C. guahibo sp. nov. Calonectria parvispora and C. spathulata were the most commonly isolated species, each of which accounted for approximately 30% of the isolates. The results suggest that Colombia has a wide diversity of Calonectria spp. and that these could challenge Eucalyptus plantation forestry in the future. [ABSTRACT FROM AUTHOR]

Draft genomes of Penicillium roqueforti, Fusarium sororula, Chalaropsis populi, and Chrysoporthe puriensis are presented. Penicillium roqueforti is a model fungus for genetics, physiological and metabolic studies, as well as for biotechnological applications. Fusarium sororula and Chrysoporthe puriensis are important tree pathogens, and Chalaropsis populi is a soil-borne root-pathogen. The genome sequences presented here thus contribute towards a better understanding of both the pathogenicity and biotechnological potential of these species. [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]