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Common hop, Humulus lupulus , is a commercially important crop in the United States, with an increasing number of hop yards being established in the Northeast. In 2018, a new fungal disease was observed at two research hop yards in Connecticut. This new pathogen affected all hop cultivars being grown and caused leaf spots and browning of cones. The causal organism was isolated and Koch's postulates were performed to confirm pathogenicity. The disease symptoms were similar to the previously described Phoma wilt; however, morphological and phylogenetic analyses placed the causal organism as a new species of Diaporthe . We propose the name Diaporthe humulicola . The disease increased under hot, humid conditions (around 24°C and 90% relative humidity), which prevail during the summer in the northeastern United States as well as other parts of the country. An in vitro preliminary assessment of fungicide sensitivity revealed that pyraclostrobin and boscalid inhibited D. humulicola growth in culture and should be further assessed for field efficacy against this new disease of hop. The proper identification and monitoring of this pathogen will be important to inform hop growers of this new threat.

A number of fir species ( Abies ) are produced as Christmas trees around the world. In particular, Fraser fir ( Abies fraseri (Pursh) Poir.) is popular as it yields high-quality Christmas trees in temperate North America and Europe. A Phytophthora sp. causing root rot on Fraser fir was isolated from a Christmas tree farm in Connecticut, U.S.A., and found to be new to science according to morphological and molecular phylogenetic analysis using multilocus DNA sequences from ITS, Cox1 , β- Tub , Nadh1 , and Hsp90 loci. Thus, it was described and illustrated as Phytophthora abietivora . An informative Koch's postulates test revealed that P. abietivora was the pathogen causing root rot of Fraser fir.

A sporodochial fungus collected from the elongate hemlock scale, Fiorinia externa (Ferris) in Coventry, Connecticut, is described. This fungus has characteristics of both Metarhizium and Myrothecium but develops setae surrounding white to buff sporodochia and dry conidia in chains, a combination of characters found in neither genus. Phylogenetic analyses of the complete small subunit ribosomal DNA (ssu), partial ef1-alpha, and complete 5.8S ribosomal DNA and internal transcribed spacers (ITS) 1 and 2 shows that the fungus is allied with a subclade within Cordyceps including the species C. agriota, which places this fungus in the Hypocreales, Clavicipitaceae sensu lato or the newly erected Ophioclavicipitaceae. Morphological observation and molecular analysis indicate that this fungus is sufficiently different from Metarhizium and Myrothecium to warrant the erection of a new anamorphic genus. Therefore Metarhiziopsis microspora gen. et sp. nov. is proposed.