The health of the forestlands of the world is impacted by a number of insect pests and some of them cause significant damage with serious economic and environmental implications. Whether it is damage of the North American cypress aphid in South America and Africa, or the destruction of maple trees in North America by the Asian long horned beetle, invasive forest pests are a major problem in many parts of the world. Several studies explored microbial control opportunities of invasive forest pests with entomopathogenic bacteria, fungi, and viruses, and some are successfully utilized as a part of integrated forest pest management programs around the world. This manuscript discusses some invasive pests and the status of their microbial control around the world with entomopathogenic fungi.

A wild, forest-dwelling cockroach from the subfamily Ectobiidae (order Blattodea) in a nature reserve in Cavalcante, in the state of Goiás, Brazil, was found to be infected by a new, genetically distinct species in the Metarhizium flavoviride species complex that we describe here as Metarhizium blattodeae. The status of this fungus as a new species is supported by both multigenic sequence comparisons and protein profiles generated by MALDI-TOF (matrix-assisted laser desorption/ionization time-of-flight) mass spectrometry. This is one of the first reports of a naturally occurring fungal pathogen affecting any sylvatic (forest-dwelling) cockroach from any part of the world. M. blattodeae caused up to 96 % mortality of Periplaneta americana nymphs (a serious peridomestic cockroach species) after 10 d.

The cypress aphid Cinara cupressi is considered one of the most important exotic invasive species in the world and now is present in all the national continental territory, affecting native forest species like ciprés de la cordillera (Austrocedrus chilensis) and alerce (Fitzroya cupressoides), as other exotic species used for ornamental trees in the urban area. The forest area of Chile has promoted and privileged the use of biological controls as part of the integrated pest management; so has Pauesia juniperorum been used to control C. cupressi; however, low levels of parasitism have been detected. Some aspects about the biology and behavior of C. cupressi and the biological control identified in our country are analyzed and discussed, as well as the measures implemented by the government considering that this was the first detection of a significant exotic pest associated with native forest species. It is proposed to assess, in the future, timing and level of parasitism of the biological control P. juniperorum, to determine if the parasitoid has been established in the whole territory or it is necessary to complement with other agents such as Lecanicillium lecanii or other biocontrol agents as Xenostigmus bifasciatus, which could be alternatively evaluated in order to reach a better control to reduce the populations of this aphid that threatens forest species of great value to our national heritage and some species used as ornamentals trees.