Humulus lupulus L., the common hop plant, is a commercially cultivated crop used as a beer flavoring agent that has been grown in Massachusetts since the 1600s (Machado et al., 2019 ; Rumney, 1998). In 2018, Diaporthe leaf spot, caused by the fungal pathogen Diaporthe humulicola, was found at hopyard research plots in Connecticut, followed by reports in multiple New York counties in 2023 (Allan-Perkins et al., 2020; Sharma et al., 2023). Additionally, Diaporthe halo blight, caused by the same fungal pathogen, was reported in Prince Edward Island (PE), Canada (Foster et al., 2024). In August of 2021, severe stem blight symptoms with visible fungal fruiting bodies were observed on >50% of plants at a hopyard in Franklin County, MA. Brown spots were observed on stems. Severe infection presented as widespread dark browning on stems, leaves, and cones. Samples were collected from the hop cultivars Mt Rainier (N=5), Magnum (N=1), and Teamaker (N=6). Under brightfield microscopy (400x) conidia congruent with Diaporthe spp. were observed on stem samples. Diseased stems from all cultivars were peeled and cut into 2 to 4 mm2 pieces, then surface sterilized in 70% ethanol for 60s, and 1% NaOCl for 60s. Samples were rinsed in sterile water, dried for 3 min and placed on potato dextrose agar (PDA). Plates were incubated at 25℃ for 5 days. 11 isolates were obtained from stem tissues of 11 plants. Isolates were cultured on PDA. 10 isolates had morphological traits consistent with the pycnidium of holotype UAMH 12076 (Allans-Perkins et al, 2020). Isolate sequences were identical, using one reinfection tests were performed on detached stem segments obtained from field grown mature plants (≥ 1 year) of cvs. Cascade and Magnum.3 wounding methods and an untreated control were used for pathogenicity testing to simulate field conditions. Each treatment had 6 replicates per cultivar and all treatments had an agar plug of inoculum applied to them, then were incubated at room temperature. Wounding with a knife involved peeling off the outer tissue layer, insect damage was simulated by using a needle to puncture the stem 3 times, and friction damage from hop support ropes was mimicked by rubbing rope against the stem. Plugs were removed 5 days post-application. Pathogenicity was observed as fungal growth and necrosis of plant tissue on all non-control methods in all samples 5 days post plug removal, fulfilling Koch's postulates. The pathogenic organism was reisolated from all inoculated tissues, except the control and identified using morphological characteristics and ITS sequence analysis. DNA amplification of the ITS region was performed according to the methods of White et al. (1990). A maximum likelihood phylogenetic tree based on the region was constructed using the MEGA10 program (Saitou & Nei, 1987). Sequence data was collected from NCBI BlastN, then aligned and trimmed. The ITS sequences (NCBI Acc. Nos. PQ555192, PQ555193, PQ555194) from the 3 isolates (UMASS001, UMASS002, UMASS003) matched 100% (543/543bp) with those of the type specimen of D. humulicola, which causes Diaporthe leaf spot and halo blight, collected in CT (NCBI Acc. No. MN152929) and 2 ex-type sequences from CT and Canada respectively (NCBI Acc. Nos. MN152927, NR172855).This is the first report of D. humulicola associated with stem blight disease. Our findings indicate that the same pathogen that infects stems can also infect cones and leaves. Therefore, Diaporthe disease management strategies should target all plant parts.

The recent discovery of obelisks, novel deltaviruses, and other viroid-like circular RNAs has greatly expanded the known diversity of autonomous RNA elements. However, cold terrestrial ecosystems remain comparatively undersampled for these molecules. Using a structure-based modification of the Tormentor pipeline, we assembled two putative non-coding rod-like circular RNAs from winter metatranscriptomes of oroarctic tundra soil collected near Kilpisjarvi, Finland. Sequence-based searches identified no meaningful homologs for either RNA. Structure-based analyses identified affinities to deltavirus-like ribozymes in Rod 1 and to hammerhead ribozymes in Rod 2, with structural compatibility confirmed by integration into an established covariation model. Rod 1 was additionally detected in independent alpine metatranscriptomic datasets, whereas Rod 2 was not identified beyond the original sample. Collectively, these results identify Rod 1 as a strong candidate viroid-like RNA bearing a putative ribozyme-like structure motif that warrants experimental validation, while Rod 1 remains a preliminary candidate requiring further confirmation.

Common hop (Humulus lupulus) is a perennial crop primarily grown as a flavouring agent for beer (Machado, 2019). It has been cultivated in Massachusetts since 1629 (Rumney, 1998). On July 31st, 2025, browning symptoms were observed in a hopyard in Northfield (42.6368 N -72.4820 W), Franklin County, MA, affecting cones, green bines, and sepals. On leaves, overlapping lesions radiated out from the leaf margins and veins. Lesions were grey or brown with a distinct chlorotic halo. Three rows of ‘Teamaker’ and ‘Centennial’ cultivars were evaluated where disease incidence was 100%. All plants showed mild to moderate disease severity, with some bines severely affected. Two samples were taken from a bine and sepal in ‘Teamaker‘ and from a leaf and petiole in ‘Centennial’. Samples were cut into 1 cm sections, surface disinfested for 30 s with 70% ethanol solution followed by 30 s of 1% NaClO solution, rinsed for 30 s in sterile water before plating on PDA. Colonies ranged from brown to dark grey with aerial mycelium. Conidia from all isolates were morphologically consistent with the Alternaria alternata species complex: brown, elliptical, concatenated, with 1-3 transverse septa and 0-1 longitudinal septa (Woudenberg et al. 2015). Genomic DNA was extracted, and PCR was performed using primers targeting the ITS region (ITS1F/ITS4), EF1 (EF1-728F/ EF1-986R), and β-tubulin (Bt2a/Bt2b) (White et al., 1990; Carbone & Kohn, 1999; Glass & Donaldson, 1995). Amplicons of ITS and TEF were obtained for both cultivars, β-tubulin was amplified for ‘Centennial’. The Nanopore sequencing (Psomagen) platform was used for sequencing. TEF sequences were identical (256/256), and ITS sequences showed 544/545 bp similarity. Sequences from the ‘Centennial’ isolate are deposited in NCBI GenBank (accession nos. PX588111, PX610247, PX610248). All sequences shared 99.7-100% identity with type sequences from the Alternaria alternata species complex (ITS 547/547bp [MH861939.1], TEF 240/240bp [KC584652.1], β-tubulin 325/326bp [JQ672038.1]). Pathogenicity was confirmed on rooted cuttings of cultivar ‘Triple Pearle’ and PI 689630. The first pair of leaves below the apical growing tip were wounded at three sites per leaf with a sterile toothpick dipped in inoculum; control wounds were untreated. For PI 689630 only one leaf served as the control. Lesions, consistent with those observed in the field, developed within 24 hours on ‘Triple Pearle’ and within 72 hours on PI 689630. No symptoms developed on control plants. Eight days post-inoculation, A. alternata was reisolated on PDA from 4/12 inoculated wounds and from 0/9 control wounds, fulfilling Koch’s postulates. Contaminants overgrew six of the isolates and one of the controls. Identification was confirmed based on colony morphology and conidial characteristics. This is the first report of Alternaria alternata species complex causing leaf spot of common hop in Massachusetts. The A. alternata species complex has previously been reported on common hop cones (Pethybridge et al., 2001). Care should be taken to minimize mechanical injury during the growing season, and rapid postharvest cone processing is recommended if symptoms are observed.

Gray snow mold, caused by Typhula incarnata, is a destructive winter disease affecting cool-season turfgrasses, typically developing under prolonged snow cover and persistently moist, cool conditions. Following snowmelt, the disease appears as large, straw-colored or matted patches, often accompanied by gray mycelium and pink sclerotia embedded within affected tissues. This study assessed the efficacy of various fungicidal treatments on a mixed Agrostis stolonifera (creeping bentgrass) and Poa annua (annual bluegrass) during the 2024 to 2025 winter season in Vermont. The results offer updated, practical recommendations for turf managers aiming to minimize damage and improve disease management strategies under typical northeastern U.S. winter conditions.