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Scotch broom (Cytisus scoparius) and French broom (Genista monspessulana) are two woody legumes native to Europe and North Africa that have become invasive in different countries around the world. In Chile, they are among the most serious invasive plants of the central southern regions, where they cause severe negative impacts to natural environments, and have become a serious problem in plantation forestry. Numerous studies have sought biological control agents for both species, however, this approach has not been explored in Chile. The aim of this study was to prospect for pathogens and diseases occurring in these weeds in invaded areas of Chile and explore these as potential biocontrol agents. Surveys were conducted in 13 invaded areas between the Biobio and Araucanía regions, and diseased plants of both species were collected for isolation. The putative pathogens isolated from each broom species were inoculated into healthy plants, and isolates producing symptoms identified by DNA sequencing. These isolates were used in pathogenicity tests on both weed species and on Pinus radiata and Eucalyptus globulus plants. The most aggressive pathogens were Fusarium sambucinum, F. solani and Phytophthora multivora on C. scoparius; Neofusicoccum parvum and Chondrostereum purpureum on both weeds, and F. tricinctum s.l. on G. monspessulana. Except for F. trincinctum s.l., all isolates caused lesions on both weeds, and except for P. multivora, all isolates caused lesions on E. globulus and/or P. radiata. Most pathogens on C. scoparius had been reported previously on this host elsewhere, while most pathogens on G. monspessulana represent novel associations. [ABSTRACT FROM AUTHOR]

Canary Island date palm, Phoenix canariensis, is a popular ornamental species commonly planted in urban areas worldwide, including South Africa. In November 2023, symptoms typical of Fusarium wilt were detected on ornamental palms at the Waterfront in Cape Town, Western Cape Province, South Africa. Samples were collected from three wilting palms with one‐sided frond death and pink sporulation on the bark. Isolations to culture media yielded two fungal species, which were confirmed based on DNA sequence data as Fusarium oxysporum f.sp. canariensis (Foc) and Nalanthamala vermoesenii. Fusarium wilt, caused by Foc, is among the most serious diseases of these palms. There is no effective treatment for this vascular wilt disease and infected palms inevitably die. Pink rot, caused by N. vermoesenii, is commonly found as a secondary infection associated with Fusarium wilt in P. canariensis. This is the first detection of the Fusarium wilt and pink rot pathogens in South Africa. [ABSTRACT FROM AUTHOR]

Araucaria araucana, (commonly referred to as araucaria, pewen, or monkey puzzle tree) is an ancient conifer endemic to the Chilean and Argentinian mountain ranges where it has a sacred relevance to indigenous communities. During 2015, a serious disease was noticed on trees of all ages in most of the natural distribution of this iconic tree. Four areas were surveyed, and the most important symptoms of the disease were cankers on branches and stems resulting in copious resin exudation. Trees were monitored for a period of two years and isolations were made from the cankers. Field observations showed that the disease typically begins on the leaves or at the leaf bases and progresses downwards to initiate cankers that can girdle branches or stems within a two‐year period. Black ascomata, resembling those of Caliciopsis species previously described from A. araucana, were consistently found developing in the cankers from which isolations were made. Phylogenetic analyses of the ITS, nucSSU, and nucLSU gene regions showed that the fungus resides in the Coryneliaceae but is distinct from other genera in that family. The morphological characteristics and phylogenetic position of the fungus show that it represents a new genus and species, described here as Pewenomyces kutranfy gen. nov. et sp. nov. Pathogenicity trials on trees under field conditions confirmed that this newly described fungus is able to cause cankers on A. araucana similar to those found under natural conditions. [ABSTRACT FROM AUTHOR]