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In August 2023, disease symptoms were noted on mint plants (Mentha arvensis) in two southwest Idaho fields with 10 to 30% of the plants exhibiting dark brown stem lesions and root necrosis. To identify the causal agent, isolations from symptomatic tissue were conducted. The surface of the disease material was treated with sodium hypochlorite (0.6%) for 1 minute and washed three times using sterile water. Approximately 2 mm³ tissue sections were cultured on water agar supplemented with 0.02% penicillin and 0.08% streptomycin and incubated at room temperature for 3-5 days. Fungal colonies were tentatively identified as Rhizoctonia from right-angle branching and septate hyphal structures, slight constriction and septum near the branch base. Single hyphal tips were transferred to potato dextrose agar (PDA) and grown at room temperature. Approximately five isolates with a consistent macromorphology were observed. These isolates had light brown mycelia and produced 1-10 mm light brown to dark irregularly shaped sclerotia after a month at ambient temperature with no exposure to continuous light. A representative isolate, designated 23D360 was selected for sequencing and pathogenicity testing. Isolate 23D360 mycelia were removed with a scalpel after 7 days of growth for DNA extraction (Synergy Kit, OPS Diagnostics, N.J., USA) and sequencing of the rDNA internal transcribed spacer (ITS) region and translation elongation factor 1α (tef1α) (Sharon et al. 2008). For ITS a 693 bp amplicon was generated and the sequence was submitted to GenBank (Accession PQ068734). NCBI-BLAST indicated this sequence was 100% identical to an isolate previously identified as R. solani AG 5 (Accession MW999177). For tef1α a 708 bp amplicon was generated and the sequence was submitted to Genbank (Accession PV021964). This tef1α sequence also had a 100% identical match to a previously characterized R. solani AG 5 strain (Accession OP832176). Final confirmation of 23D360 was done using an AG 5 specific real-time PCR assay which targets the beta-tubulin gene (Budge et al. 2009). Pathogenicity testing was performed twice on thirteen 1-week-old mint transplants cultivar 'Black Mitcham Scottish' grown in premium potting compost (Scotts) in greenhouse conditions (30°C, 12h daylight). Barley seeds soaked in water overnight were autoclaved twice, inoculated with a mycelial plug of isolate 23D360 and incubated for 2 weeks at ambient room temperature (25°C). Barley seed inoculum (5 g) was placed around each transplant at the root and stem convergence point. Thirteen 1-week-old transplants were mock-inoculated with autoclaved barley seeds as a control. Approximately 23% damping-off incidence was observed on inoculated transplants five days post-inoculation, while control transplants remained healthy. At 21 days post-inoculation, plants were assessed for visible stem lesions and root necrosis. The incidence of stem lesions occurred on 80% of seedlings, with all transplants with stem lesions ranging from 1-4 cm in diameter and root necrosis. No inoculated transplants were free of stem lesions and root necrosis. R. solani was re-isolated from symptomatic tissue, with a 90% isolation frequency, and rDNA ITS sequencing was used to confirm identity as AG 5, thus confirming Koch's postulates. R. solani was reported in mint in Florida (Alfieri et al., 1984), Indiana (Green, 1961), North Carolina (Grand, 1985), the Pacific Northwest of Oregon (Horner, 1952), and Washington (Shaw, 1973) but not in Idaho. No information on anastomosis groupings was reported in previous literature. Nitzan et al. (2012) identified a new disease affecting Mentha longifolia, a species of mint produced and exported from Israel. Two isolates from symptomatic plants were identified as R. solani AG 1-IB and 4 HG-I. To our knowledge, the isolate 23D360 described here, is the first record of R. solani AG 5 in mint in Idaho. Idaho ranks second in U.S. peppermint production where much of the mint is concentrated in the southwest of the state, this report will create awareness among mint growers on the presence of this fungal disease.

Fusarium dry rot is a ubiquitous disease of potato affecting tubers in storage and at planting. A greater understanding of the current Fusarium species composition associated with Fusarium dry rot in the Pacific Northwest (PNW) will aid in refinement of current management strategies. In this study, the identity of 327 single-spore Fusarium isolates recovered from PNW tuber samples was confirmed using molecular phylogenetic analyses based on partial sequences of tef and pho loci. Of the twenty species recovered, Fusarium sambucinum was the most prevalent (44.6%), followed by Fusarium oxysporum (13.8%). Selected isolates were tested for pathogenicity to potato tubers. Pathogenicity was confirmed for fourteen species of Fusarium, including seven species not previously reported as Fusarium dry rot pathogens in the region. On potato cv. 'Russet Burbank' (RB), inoculation with isolates of F. sambucinum resulted in the largest lesions (19.5-27.7 cm2), followed by isolates of F. avenaceum, F. cerealis, F. culmorum, F. flocciferum, F. graminearum, F. oxysporum, F. redolens, F. sporotrichioides, and F. venenatum (2.0-13.1 cm2). Inoculation with F. acuminatum, F. equiseti, F. solani, and F. stercicola resulted in the smallest lesions (0.1 to <2.0 cm2). An isolate of F. redolens caused lesions that were 5.7-fold larger on potato cv. 'Dark Red Norland' compared to those on RB (13.1 and 2.6 cm2, respectively), indicating variety selection may play a role in managing Fusarium dry rot. Diversity of Fusarium species pathogenic to potato in the PNW is greater than previously reported. Management strategies should consider potato variety, pathogen species, and isolate aggressiveness.

In July 2022, stem lesions, approximately 4 to 5 cm in length as well as leaf wilt and dark brown necrosis on stems and roots were observed in two fields in Southwest Idaho on 20 to 30% of watermelons (Citrullus lanatus). To determine the causal agent, isolations were attempted from symptomatic tissue. The surface of the affected material was disinfected with 0.6% sodium hypochlorite for 1 min and rinsed three times with sterile water. Approximately 2 mm3 sections of tissue were plated on water agar amended with 0.02% penicillin and 0.08% streptomycin and incubated at room temperature for 7 days. Fungal colonies were tentatively identified as Rhizoctonia from right-angle branching and septate hyphal structures, slight constriction and septum near the branch base, and the production of 1 to 2 mm white to light brown irregularly shaped sclerotia. Single hyphal tips were transferred to potato dextrose agar (PDA) and grown at room temperature. Approximately ten isolates from each field with a consistent macromorphology were observed. These isolates had light brown mycelia, produced sclerotia at ambient temperature with no exposure to continuous light, and a representative isolate, designated D22-110 was selected for sequencing and pathogenicity testing. For isolate D22-110, mycelia were removed with a scalpel after 7 days of growth, for DNA extraction and sequencing of the rDNA internal transcribed spacer (ITS) region as previously described (White et al., 1990). A 726 bp product was generated and the sequence was submitted to GenBank (Accession No. OQ794049). NCBI-BLAST indicated this sequence was 99% identical (631 of 634 bp and 632 of 634 bp identical) with known reference isolates previously identified as R. solani AG 4 HG-III (Accession No. AF354075 and AF354076, respectively) from a phylogenetic study (Gonzalez et al., 2001). Pathogenicity testing was performed twice on two-week-old seedlings of watermelon cultivars Endless Summer and Wingman in greenhouse conditions (29oC, 12 h daylight). Two disks (3 mm diam) from 7-day-old plates of PDA were placed around each seedling at the root and stem convergence point. Ten seedlings were mock-inoculated with sterile PDA plugs as a control. Approximately 35% damping-off incidence was observed on inoculated seedlings six days post-inoculation, while control seedlings remained healthy. At 20 days post-inoculation, 20 (first trial) and 34 seedlings (second trial) were assessed for visible stem and root lesions. Incidence of stem lesions occurred on 90% of seedlings, with 80% of seedlings possessing lesions greater than 10 mm in diameter. Seedlings without R. solani inoculation were free of stem and root lesions. R. solani was re-isolated from symptomatic tissue, with 40% frequency of isolation, identified by right-angle branching of the hyphae thus confirming Koch's postulates. R. solani AG 4 has been reported in watermelon in the US since 1994 (Hall and Summer, 1994) but the AG 4 subgroup was not reported. AG 4 HG-III was reported in melon seedlings causing damping-off in Kyrgyzstan (Erper et al. 2016). In other hosts, AG 4 HG-III was found in potatoes in South Africa (Muzhinji et al., 2014), buckwheat and foxtail millet in China (Zhou et al., 2015; Hao et al., 2023), broccoli and spinach (Kuramae et al., 2003) and turnip green (Sekiguchi et al., 2015). To the best of our knowledge, this is the first report of R. solani AG 4 HG-III causing disease in watermelon in Idaho. Given the the rate of disease incidence observed in the field, growers should consider avoiding planting alternative host crops to minimize inoculum buildup.

Since 2018, bleeding cankers have been observed on maple trees in multiple home gardens in southwest Idaho. The cankers ooze a dark sap and and are approximately 10 cm to 35 cm in diameter. Cankers typically occur on the main trunk but are also present on scaffold branches in severe infecrions. Symptoms of foliar chlorois, branch dieback, and premature autumn senescence were also associated with the disease. Phytophthora DNA was detected in symptomatic material from five trees using real-time PCR (Miles et al., 2017). In July 2019 recovery of a causal agent from a symptomatic Acer x freemanii tree was attempted. Excisions were made from the interface of healthy and diseased tissue around the cankers using a chisel. The tissue was then placed in sealed plastic ziplock bags at 4°C for 7 days. Hyphae were then removed with forceps and placed onto potato dextrose agar (PDA) amended with penicillin G (0.2 g/liter) and streptomycin sulfate (0.8 g/liter). Colonies resembling Phytophthora cactorum were consistently observed after 5 days at 21°C. Tentative P. cactorum identification was based on the presence of abundant papillate and caducous sporangia on a short pedicel; sporangia were approximately 30 μm long and 26 μm wide (Bush et al., 2006; Hudler, 2013). Individual hyphal tips were transferred to fresh PDA plates and sequencing of both the rDNA ITS region and Cytochrome c oxidase subunit I (COI) was completed for a representative isolate (D19-130). DNA extraction, PCR and sequencing were as previously described (Woodhall et al. 2013; Robideau et al., 2011). The resulting DNA sequences for rDNA ITS (MW315449) and COI (MW881040) were both 100% identical (723/723 bp and 728/728 bp) with sequences from cultures previously identified as P. cactorum (MH171627 and MH136858). To determine pathogenicity, 14 month-old maple (A. x freemanii) trees in individual containers with potting mix were wounded 15 mm above the soil line with a single 10 mm incision using a sterile razor blade and inoculated by placing a 10 mm2 fully colonized PDA plug of isolate D19-130 on the wound. The inoculum and wound were then covered with a damp cotton ball that was secured loosely with parafilm. Control plants consisted of uninoculated plants and wounded plants inoculated with a PDA agar plug. Each treatment was replicated five times and placed in a controlled environment chamber set at 24ºC and 90% relative humidity. All treatments were sprayed with water daily to ensure the cotton balls remained damp. After 8 weeks, black lesions, up to approximately 25 mm above the soil line, were observed on the stem base of all P. cactorum-inoculated plants. No black lesions were observed on non-inoculated plants or plants inoculated with a PDA agar plug. P. cactorum was isolated from lesions, as described above, except polystyrene foam boxes containing moist paper towels were used instead of bags. This report confirms P. cactorum as a causal agent of bleeding canker of maple in Idaho for the first time. It has been shown that several Phytophthora species can infect maple (Jung and Burgess, 2009; Huddler, 2013). P. cactorum has a wide host range but certain strains have been associated with lethal bleeding stem cankers in maple and other deciduous trees worldwide (Huddler, 2013). Knowledge of the causal agent of bleeding canker on maple will help determine appropriate disease management practices.

Background: This study analyzed data from the 2017 American College of Surgeons National Trauma Data Bank to examine the effects of pre-hospital Field Triage Decision Scheme Step 1 vital sign criteria (S1C) and vital sign decline on subsequent emergency department (ED) and hospital death in emergency medical services (EMS) transported trauma victims., Study Design: Patient and injury characteristics, transport time, and ED and hospital disposition were collected. S1C (respiratory rate [RR]<10, RR>29 breaths/min, systolic blood pressure [SBP]<90 mmHg, Glasgow Coma Scale [GCS]<14) were recorded at the injury scene and hospital arrival. Decline was defined as a change ≥ 1 standard deviation (SD) into or within an S1C range. S1C and decline were analyzed relative to ED and hospital death using logistic regression., Results: Of 333,213 included patients, 54,849 (16.5%) met Step 1 criteria at the scene, and 21,566 (6.9%) declined en route. The ED death rate was 0.4% (n = 1,188), and the hospital death/hospice rate was 4.0% (11,624 of 287,675). Patients who met S1C at the scene or who declined were more likely to require longer hospital lengths of stay, ICU admission, and surgical intervention. S1C and decline patients had higher odds of death in both the ED (S1C odds ratio [OR] 15.1, decline OR 2.4, p values < 0.001) and hospital (S1C OR 4.8, decline OR 2.0, p values < 0.001) after adjusting for patient demographics, transport time and mode, injury severity, and injury mechanism. Each S1C and decline measure was independently predictive of death., Conclusions: This study quantifies the mortality risks associated with individual S1C and validates their use as an indicator for injury severity and pre-hospital triage tool., (Copyright © 2020 American College of Surgeons. Published by Elsevier Inc. All rights reserved.)

In 2014, glasshouse-grown wasabi (Eutrema japonica) grown in a compost based media displayed symptoms of poor growth and wilting. Visual assessment of the roots showed that 25% of the symptomatic plants sampled had raised black lesions on the roots affecting between 5 and 20% of the total root area. To isolate the causal agent, affected material (approximately 5 mm3) was surface disinfested in sodium hypochlorite (2%) for 30 s, rinsed twice in sterile water and plated on to water agar medium amended with penicillin G (0.2 g/liter) and streptomycin sulfate (0.8 g/liter). Plates were incubated at 20ºC until fungal colonies were visible. After three days, colonies of Rhizoctonia solani were identified based on the presence of septate hyphae with right-angle branching, a pure culture was obtained through hyphal tip transfer onto a new plate of PDA. DNA was extracted from a 7-day old plate of the isolate (WAS1) as described previously (Woodhall et al., 2013). The AG of WAS1 was determined as AG2-1 using a subgroup specific real-time PCR assay (Budge et al., 2009b) and confirmed by DNA sequencing as described previously (Lekuona Gomez et al., 2015). The sequence was 100% identical (587/587bp) to a previously identified AG2-1 isolate 1971 (GenBank accession FJ435126) (Budge et al., (2009a). Pathogenicity of the isolate was confirmed by inoculating three healthy one-year-old wasabi plants grown in loam based compost (John Innes No.3) each with four 5 mm fully colonised PDA plugs of isolate WAS1 placed at approx. 40 mm depth in the soil. Four sterile PDA plugs were place in each of three control plants. All six plants were placed in a greenhouse at 21°C, 18h:6h light: dark and watered as required. After 21 days, multiple black root lesions typically 3-5mm in length were observed on the roots of all inoculated plants. No lesions were observed on the control plants. From three lesions per plant, isolations were attempted as described above. Rhizoctonia solani was recovered from all isolations and the resulting cultures all tested positive for AG2-1 using the real-time PCR assay. Isolations were attempted from the roots of healthy control plants but Rhizoctonia was not recovered. Here we demonstrate that R. solani AG2-1 is associated with root necrosis of Eutrema japonica. Rhizoctonia solani AG2-1 has been reported previously in various Brassica crops in the UK (Budge et al., 2009a) and on Matthiola incana (Lekuona Gómez et al., 2015). It has also been reported causing disease in potatoes and as widely present in UK field soils (Woodhall et al., 2013). Although R. solani AG1 and AG4 of R. solani have been reported to infect Eutrema japonica in Japan (Takeuchi et al., 2003; 2008), this is the first finding that identifies AG2-1 as the causal agent. The potential presence of AG2-1 in soil and/or as plant debris should be considered prior to planting susceptible hosts.

Rubbery rot of potato caused by Geotrichum candidum Link is characterized by symptoms of damp, flaccid tubers that feel rubbery when squeezed (Humpreys-Jones 1969), similar in consistency to potato diseases such as pink rot (caused by Phytophthora erythroseptica) and Pythium leak (caused by species of Pythium). In November 2019, several symptomatic tubers of potato variety 'Ciklamen' that had been held in storage since harvest and originated from an over-head irrigated, sandy-loam production field in Bingham county, Idaho were submitted to the University of Idaho for diagnosis. Shipping-point inspection records indicated 4-9% of tubers were affected. External symptoms included irregularly shaped, randomly located sunken black-colored lesions on more severely affected rubbery-textured tubers. When cut, internal affected tissue developed a greyish appearance after several minutes. Lens-shaped cavities were apparent in two of the tubers, indicating an advanced infection. A sour-milk smell accompanied the sample. To isolate the pathogen, pieces of tuber tissue approximately 5 mm in diameter were collected from the margins of symptomatic areas and surface-sanitized in sodium hypochlorite (2%) for two minutes, rinsed twice in sterile water and plated onto tap water agar amended with penicillin G (0.2 g/liter) and streptomycin sulfate (0.8 g/liter). After three days at 21°C, colonies having distinct creamy white mycelia, a sweet, juniper-like odor, and hyaline hyphae were consistently associated with diseased tissue. Cylindrical to oval-shaped arthroconidia ranged in size from 6.6-11.0 × 3.2-5.9 μm (mean = 8.4 × 4.7, n=21), within dimensions as reported by Carmichael (1957). No other pathogens including species of Pythium and Phytophthora were recovered from the sample. Pure cultures were obtained by transferring hyphal tips to potato dextrose agar plates. Species identity was confirmed via rDNA ITS sequencing using primers ITS5/4 (White et al., 1990). DNA extraction and PCR conditions were as previously described (Woodhall et al., 2013). Resulting sequences (NCBI accession numbers MT893312 and MT893315) shared 99.4% identity with G. candidum Accession KY103453.1 on GenBank. To confirm pathogenicity, ten tubers (cv. Ciklamen) were inoculated by placing a 10mm2 plug of fully colonized PDA of G. candidum on the tuber surface, and ten tubers were mock inoculated with sterile PDA plugs. After 27 days at 21C in a dew chamber, tubers were examined for symptoms. Eight of the 10 inoculated tubers exhibited a rubbery texture and fluid leaking from tubers when cut, with two tubers also exhibiting a grey internal discoloration and the distinctive smell. Control tubers did not exhibit any symptoms. Isolations were attempted from four symptomatic tubers and G. candidum was successfully recovered from three tubers. The disease has been reported sporadically in the United Kingdom (Humphreys-Jones 1969) and Korea (Kim et al., 2011) and the pathogen occurs worldwide (Carmichael 1957). Though the fungus causes a tomato rot in the United States (US) (Pritchard and Porte, 1923; Bourret et al., 2013), and potatoes with rubbery rot originating from Australia were intercepted at a US port (Farr et al., 2020), the disease has not to our knowledge been documented on potato grown in the US. Because symptoms may be confused with pink rot and Pythium leak, it is critical for producers to obtain a correct diagnosis to facilitate appropriate management strategies.

In September of 2018, onion plants (Allium cepa cv. Joaquin) grown in one field in southwest Idaho were observed to have roots with brown discoloration over 10-20% of the total root surface area. Approximately 10% of plants over a 1 ha area were affected and these plants were about visually 50% smaller than the typical bulb size present in the field. To determine the causal agent, 3 mm pieces of symptomatic roots from four plants were placed in sodium hypochlorite (2%) for one minute, followed by two rinses in sterile water and plated on to water agar medium amended with penicillin G (0.2 g/liter) and streptomycin sulfate (0.8 g/liter). After 3 days at 21°C, fungal colonies with septate hyphae with right-angled branching resembling Rhizoctonia solani were observed in over half of the 16 isolations attempted. Species identity was confirmed through rDNA ITS sequencing, as described previously (Woodhall et al., 2013), with DNA obtained from a single representative hyphal tip culture grown on Potato Dextrose Agar (PDA) which was designated isolate ON3. The resulting sequence (MT672318), was 100% identical (678/678bp) to a sequence previously identified as R. solani AG 2-2 IIIB on GenBank (FJ492137). Pathogenicity of the culture was determined by inoculating ten 20-day-old plants (cv. Joaquin) grown in premium potting compost (Scotts) with a single, fully colonized 10 mm2 plug taken from a 2-week-old PDA culture of isolate ON3. A further nine plants were inoculated with sterile PDA plugs as controls. Plants were grown in the greenhouse at 21C in a 16-hour light regime. After 24 days, each plant was assessed for root rot disease as described previously (Misawa et al. 2017). Root rot was observed on nine of the inoculated plants. Mean diseased root area was 32% of the total root surface, with a minimum of 5% and a maximum of 100% diseased root area and a standard deviation equal to 39.6. No root browning was observed on any of the control plants. Isolations were attempted from nine symptomatic plants and R. solani was successfully isolated from seven plant samples onto water agar. Sequencing was used to confirm identity as AG2-2IIIB. To our knowledge, this is the first report of R. solani AG 2-2 IIIB affecting onions in Idaho. Previous work in the Pacific Northwest recovered R. solani AG2-1, 3, 4 and 8 and also BNR AG A from stunted onions (Patzek et al., 2013). In Japan, Misawa et al. (2017) found AG 2-2 IIIB to be pathogenic to Welsh onion (Allium fistulosum). In Idaho, R. solani AG 2-2 IIIB has was previously reported causing disease in sugar beets (Strausbaugh et al. 2011) and potatoes (Woodhall et al. 2012). Growers should consider crop rotation strategies or soil treatments if R. solani AG2-2IIIB is causing disease in their crops.

In September 2014, a high rate of bulb rot (5-15% depending on producer) was reported across all cultivars developing early in the storage season in the onion producing region of southwestern Idaho. Spanish yellow onion bulbs cv. Vaquero displaying tan to light brown necrotic rot were obtained. The bulb rot originated in the neck and spread to successive scales (Figure 1). In August 2015, onion cv. Redwing and Vaquero were observed to have wet necrotic lesions developing on leaves in the field (Figure 2). Margins of necrotic tissue, 1-2 cm 3 , were excised, surface sterilized, plated on water agar medium and incubated at 24°C. Hyphal growth was sub-cultured from eight strains (A- D in 2014; E-H in 2015) to fresh potato dextrose agar to obtain pure cultures. Cultures were characteristic of Fusarium species as described by Nelson et al. (1983) with the presence of microconidia formed on polyphialides with macroconidia present. Primers ITS4-A1 and ITS5 primers (White et al. 1990); EF-1 and EF-2 (O'Donnell et al. 1998); and fRPB2-5F and fRPB2-7cR (Liu et al. 1999) were used to amplify regions of the ITS, elongation factor 1-α and the second largest subunit of DNA-directed RNA polymerase II. Amplicons were sequenced and analyzed using BLAST (https://www.ncbi.nlm.nih.gov/) and in combination using Pairwise DNA Alignment and Polyphasic Identification (http://www.westerdijkinstitute.nl/Fusarium/DefaultInfo.aspx?Page=Home) as described by O'Donnell et al. 2015. Analysis indicated that these strains are Fusarium proliferatum , which is part of the F. fujikuroi species complex (O'Donnell et al. 1998). Similarity (99.5%) was observed in pairwise analyses and the polyphasic identification clustering to representative F. proliferatum strain NRRL 22944 and others. Sequences were submitted to Genbank and registered accession numbers are found in Table 1. To complete Koch's postulates, cv. Vaquero onion bulbs were surface sterilized and injected with 3 × 10 5 microconidia into the shoulder of each bulb. Five bulbs were inoculated for each isolate, placed in a mesh bag, and incubated at 30°C in the dark. Five bulbs injected with sterile water and five non-inoculated bulbs served as controls. After 14 days, each bulb was sliced vertically down the center and inspected for rot. All eight strains induced tan to light brown necrotic rot symptoms in each inoculated bulb. No symptoms were observed for the water inoculated and the non-inoculated onion bulbs. A fungus was isolated from the necrotic tissue and confirmed to be F. proliferatum as described above. Ten µl aliquots containing 1 × 10 5 microconidia of F. proliferatum strains (C, E-H) were applied to leaves in triplicate of 12-week-old onion plants (cv. Vaquero) wounded with a 21-gauge needle. Water controls were included. Within three days lesions, with light chlorosis, began to form and quickly spread on the leaves. A fungus was isolated and confirmed to be F. proliferatum as described above. This is the first extensive description and identification of F. proliferatum causing bulb rot in storage in Idaho (Mohan et al. 1997). In addition, this is the first report of the fungus causing leaf infection in the field. These findings confirm F. proliferatum as the causal agent of the high incidence of bulb rot observed in 2014 and 2015. This bulb rot continues to occur in southwestern Idaho and since the pathogen can cause leaf infections growers are encouraged to be vigilant for both leaf lesions during the growing season and bulb rot in storage.

Background and Study Aims:  Findings in the literature are conflicting on whether trainee involvement in endoscopic retrograde cholangiopancreatography (ERCP) procedures is detrimental to cannulation success rates. We addressed this in a prospective study, where cannulation success with or without trainee presence was the primary outcome measure., Patients and Methods:  We prospectively recorded data on 2 senior endoscopists and their trainees over an 18-month period for ERCPs in patients with a virgin ampulla. Presence or absence of a trainee at ERCP procedures was pragmatic, reflecting their other service or training commitments or annual leave. For trainee presence, the training protocol allowed them 6 minutes of supervised time in which to achieve biliary cannulation after reaching the ampulla. Study outcome measures included cannulation success, time to cannulation, technique, whether this was achieved independently by the trainee, and complications., Results:  There were 219 procedures recorded and analyzed (134 with a trainee, 85 without). Three trainees were involved. Selective biliary cannulation was achieved in 201 (92 %) of cases. When a trainee was present, cannulation was successful in 122/134 procedures (91 %), compared to 79/85 (93 %) with a senior endoscopist alone ( P  = 0.8, Fisher's exact test). Mean time to biliary cannulation with a trainee present was 7 minutes, compared with 5 minutes with no trainee. Mean time for successful independent cannulation by the trainee was 4 minutes, and 9 minutes for a consultant following a trainee's attempt. There were no serious adverse events., Conclusion:  Our study shows that with this training protocol, involvement of a trainee on a routine secondary care ERCP list does not impair biliary cannulation success, and does not prolong a subsequent attempt by the senior endoscopist if initially unsuccessful. These findings support the involvement of trainees in routine ERCP lists with this training protocol.

The Voyager 1 planetary radio astronomy experiment detected two distinct kinds of radio emissions from Saturn. The first, Saturn kilometric radiation, is strongly polarized, bursty, tightly correlated with Saturn's rotation, and exhibits complex dynamic spectral features somewhat reminiscent of those in Jupiter's radio emission. It appears in radio frequencies below about 1.2 megahertz. The second kind of radio emission, Saturn electrostatic discharge, is unpolarized, extremely impulsive, loosely correlated with Saturn's rotation, and very broadband, appearing throughout the observing range of the experiment (20.4 kilohertz to 40.2 megahertz). Its sources appear to lie in the planetary rings.

We report results from the first low-frequency radio receiver to be transported into the Jupiter magnetosphere. We obtained dramatic new information, both because Voyager was near or in Jupiter's radio emission sources and also because it was outside the relatively dense solar wind plasma of the inner solar system. Extensive radio spectral arcs, from above 30 to about 1 megahertz, occurred in patterns correlated with planetary longitude. A newly discovered kilometric wavelength radio source may relate to the plasma torus near Io's orbit. In situ wave resonances near closest approach define an electron density profile along the Voyager trajectory and form the basis for a map of the torus. Detailed studies are in progress and are out-lined briefly.

Planetary radio astronomy measurements obtained by Voyager 2 near Saturn have added further evidence that Saturnian kilometric radiation is emitted by a strong dayside source at auroral latitudes in the northern hemisphere and by a weaker source at complementary latitudes in the southern hemisphere. These emissions are variable because of Saturn's rotation and, on longer time scales, probably because of influences of the solar wind and Dione. The electrostatic discharge bursts first discovered by Voyager 1 and attributed to emissions from the B ring were again observed with the same broadband spectral properties and an episodic recurrence period of about 10 hours, but their occurrence frequency was only about 30 percent of that detected by Voyager 1. While crossing the ring plane at a distance of 2.88 Saturn radii, the spacecraft detected an intense noise event extending to above 1 megahertz and lasting about 150 seconds. The event is interpreted to be a consequence of the impact, vaporization, and ionization of charged, micrometer-size G ring particles distributed over a vertical thickness of about 1500 kilometers.

Within distances to Uranus of about 6 x 10(6) kilometers (inbound) and 35 x 10(6) kilometers (outbound), the planetary radio astronomy experiment aboard Voyager 2 detected a wide variety of radio emissions. The emission was modulated in a period of 17.24 +/- 0.01 hours, which is identified as the rotation period of Uranus' magnetic field. Of the two poles where the axis of the off-center magnetic dipole (measured by the magnetometer experiment aboard Voyager 2) meets the planetary surface, the one closer to dipole center is now located on the nightside of the planet. The radio emission generally had maximum power and bandwidth when this pole was tipped toward the spacecraft. When the spacecraft entered the nightside hemisphere, which contains the stronger surface magnetic pole, the bandwidth increased dramatically and thereafter remained large. Dynamically evolving radio events of various kinds embedded in these emissions suggest a Uranian magnetosphere rich in magnetohydrodynamic phenomena.

Detection of very intense short radio bursts from Neptune was possible as early as 30 days before closest approach and at least 22 days after closest approach. The bursts lay at frequencies in the range 100 to 1300 kilohertz, were narrowband and strongly polarized, and presumably originated in southern polar regions ofthe planet. Episodes of smooth emissions in the frequency range from 20 to 865 kilohertz were detected during an interval of at least 10 days around closest approach. The bursts and the smooth emissions can be described in terms of rotation in a period of 16.11 +/- 0.05 hours. The bursts came at regular intervals throughout the encounter, including episodes both before and after closest approach. The smooth emissions showed a half-cycle phase shift between the five episodes before and after closest approach. This experiment detected the foreshock of Neptune's magnetosphere and the impacts of dust at the times of ring-plane crossings and also near the time of closest approach. Finally, there is no evidence for Neptunian electrostatic discharges.

The Voyager 2 Planetary Radio Astronomy experiment to Jupiter has confirmed and extended to higher zenomagnetic latitudes results from the identical experiment carried by Voyager 1. The kilometric emissions discovered by Voyager 1 often extended to 1 megahertz or higher on Voyager 2 and often consisted of negatively or, less frequently, positively drifting narrowband bursts. On the basis of tentative identification of plasma wave emissions similar to those detected by Voyager 1, the plasma torus associated with Io appeared somewhat denser to Voyager 2 than it did to Voyager 1. We report here on quasiperiodic sinusoidal or impulsive bursts in the broadcast band range of wavelengths (800 to 1800 kilohertz). A Faraday effect appears at decametric frequencies, which probably results from propagation of the radiation near its sources on Jupiter. Finally, we discuss the occurrence of decametric emission in homologous arc families.

The planetary radio astronomy experiment on board the Voyager spacecraft has detected bursts of nonthermal radio noise from Saturn occurring near 200 kilohertz, with a peak flux density comparable to higher frequency Jovian emissions. The radiation is right-hand polarized and is most likely emitted in the extraordinary magnetoionic mode from Saturn's northern hemisphere. Modulation that is consistent with a planetary rotation period of 10 hours 39.9 minutes is apparent in the data.

Since the spring of 1960 a strong positive correlation between Jupiter's decametric emission and solar decametric continuum emission observed at Boulder has been evident. The time delay of 1 to 2 days, with solar emission preceding Jupiter's emission, suggests that fast solar corpuscles, at velocities of the order of 0.1 c, are directly involved in the planet's atmosphere or magnetic field.

Some decametric radio emissions from Jupiter observed recently exhibit effects which are attributable to Faraday rotation within the earth's ionosphere. We present the evidence for the presence of Faraday rotation and discuss its origin. Identification of the magnetoionic mode in which the emission is generated at Jupiter appears possible, although near the limit of accuracy of our present observations. The emission seems to be generated in the extraordinary mode.