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Cranberry (Vaccinium macrocarpon Ait.) vines (cv. Howes) from a commercial cranberry bed on Nantucket Island displayed typical symptoms of rose bloom disease in June, 1997. The affected area (1.5 × 30.0 m) consisted of less than 1% symptomatic uprights and was not covered by sprinkler heads of the chemigation system. The same area that did not receive insecticides or fungicides was damaged by black-headed fireworm (Rhopobota naevana) feeding during the 1996 growing season. The surface of the leaves on the abnormal branches displayed the typical white, powdery external appearance, which consisted of basidia and basidiospores of the pathogen Exobasidium oxycocci Rostr. ex Shear that were hyaline, fusiform with a slight curvature, and measured 14 to 18 × 2 to 3 μm, matching a previous description (2). Plants showing symptoms had been infected during 1996. Abnormal lateral shoots with swollen pink leaves grew from infected axillary buds on the previous year's wood (3). Cranberry plants were inoculated with basidiospores but symptoms may take longer than 1 year to develop. Rose bloom was formerly a common disease affecting cranberry in Massachusetts and control strategies were addressed in the disease management recommendations sent out by the Cranberry Experiment Station to growers through 1954. Bergman (1) reported that the disease was found almost every year before 1945, but since then there were no serious outbreaks, possibly due to changes in cultural practices. The fungicide ferbam (ferric dithiocarbamate) largely replaced Bordeaux mixture as a fungicide to combat fruit rot in the late 1940s. The disease was not brought in with imported vines from the Pacific Northwest, where the disease is common, because the vines in this bed were planted in 1910. The disease has not been observed in either wild or abandoned cranberry beds that have not received fungicide applications. This is the first report of this disease in Massachusetts in nearly 50 years. References: (1) H. F. Bergman. 1953. Yearbook of Agriculture, p. 792. (2) F. L. Caruso and D. C. Ramsdell, eds. 1995. Compendium of Blueberry and Cranberry Diseases. American Phytopathological Society, St. Paul, MN. (3) C. L. Shear et al. 1931. U.S. Dep. Agric. Tech. Bull. 258.

BACKGROUND Cranberry fruit (Vaccinium macrocarpon) is rich in polyphenols, particularly oligomeric proanthocyanidins (PACs) possessing antimicrobial and antioxidant properties. PACs may play a role in resistance to fruit rot. Although many cranberry cultivars are grown for use in foods, beverages and nutraceuticals, data on PAC content among cultivars is limited. Eight cultivars were sampled from four growing regions during the 2010 season and analyzed for PAC content and composition. RESULTS MALDI-TOF MS showed that isolated PACs had similar oligomer profiles among cultivars. The major constituents were A-type (epi)catechin oligomers of two to eight degrees of polymerization. Total PAC content ranged between 18 and 92 g PAC kg−1 dried fruit, quantified as procyanidin A2 by the dimethylaminocinnamaldehyde method. Among the cultivars sampled, Howes had the highest total PACs (76–92 g kg−1), followed by Mullica Queen and Early Black (48–82 g kg−1). Ben Lear, a disease-susceptible variety, was significantly lower in PACs than the other cultivars (P < 0.001). CONCLUSIONS Several traditional and newer cultivars of cranberry from various growing regions in North America are excellent sources of PACs, particularly the Howes, Mullica Queen and Early Black cultivars. PAC content may play a role in keeping quality. © 2014 Society of Chemical Industry

Sudden vegetation dieback (SVD) is defined as the loss and lack of recovery of smooth cordgrass (Spartina alterniflora) in salt marshes. A new species of a moderately pathogenic fungus called Fusarium palustre is consistently found in SVD sites, but greenhouse tests revealed that it is not capable of causing mortality of healthy plants. Similarly, root-knot nematodes (Meloidogyne spartinae) are also found in SVD sites, but their incidence in marshes affected by SVD is not known. To understand more about the ecology of F. palustre and M. spartinae, salt marshes along Connecticut's Long Island Sound and Massachusetts' Cape Cod that exhibited SVD and those that did not, were visited during the summers of 2007, 2008, and 2009. Belowground and aboveground tissues of smooth cordgrass plants from 18 marshes were removed, washed, and assayed for Fusarium spp. to determine if patterns between the incidence of the different species of Fusarium, their virulence on S. alterniflora, root-knot nematodes (M. spartinae), and the health of the marsh could be revealed. There were significantly more colonies of Fusarium growing from plants in SVD sites (6.1%) than in healthy marshes where no SVD was present (

Flooding is an inexpensive cultural practice used for pest management in Massachusetts cranberry (Vaccinium macrocarponAit.) production. This project examined the use of short-term floods (Cuscuta gronoviiWilld.) management under controlled conditions. Using incubators, seed was submerged in water for 0, 24 and 48 h at 10, 15 and 20°C (simulating spring water temperatures) and 0, 12, 24, 36 and 48 h at 15, 20 and 25°C (simulating summer water temperatures). Two 1-year controlled studies (field and greenhouse) evaluated three flood durations (0, 24 and 48 h) and four flood initiations (1, 2, 3 and 4 weeks after early seedling emergence (AEE)). Treated seeds were planted to cranberry vines and to Petri dishes; percent germination, degree of dodder attachment and dodder biomass data were collected. Treatments had limited effect on seed germination. Flooding 4 weeks AEE resulted in the lowest mean attachment ratings and dodder stem biomass on cranberry. This preliminary work provides evidence that flooding may retard dodder stem growth rather than reducing seed germination and that floods initiated after some time has elapsed after early emergence may be more effective than those initiated closer to the time of seedling emergence. More information is needed to thoroughly understand the processes involved; however, small projects such as this can provide interim guidelines that growers can immediately consider when deciding on a dodder management program.

Cranberry fruit rot (CFR) is caused by many species of fungi, with the contribution of any given species to the disease complex varying among plantings of Vaccinium macrocarpon within a site, sites within regions, and among regions and years. This study assessed the morphological and molecular variability of five widespread CFR-causing fungi: Phyllosticta vaccinii, Coleophoma empetri, Colletotrichum acutatum, Colletotrichum gloeosporioides and Physalospora vaccinii. Although the majority of isolates had morphological characteristics consistent with published descriptions, some were atypical. For example, non-chromogenic isolates of C. acutatum were recovered from British Columbia and white isolates of Physalospora vaccinii were recovered in addition to the more common dark isolates. On the basis of sequence analysis of the ITS and large subunit rDNA (LSU), it appears that Phyllosticta vaccinii, C. empetri, C. gloeosporioides and C. acutatum are genetically uniform on cranberry in North America. This suggests the possibility that these fungal species were introduced to cultivated cranberries and concomitantly moved with planting material to new locations. In contrast, white isolates of Physalospora had ITS and LSU sequences distinct from those of their dark counterparts, with phylogenetic analyses suggesting that these isolates represent either different species or distinct members of highly divergent populations. Taxonomic placement of all species based on phylogenetic relationships was consistent with morphological placement, with the exception of Physalospora vaccinii. Unlike other Physalospora species, CFR isolates of Physalospora vaccinii were not allied with the Xylariomycetidae; instead, these fungi were members of the Sordariomycetidae. A deeper taxonomic analysis is needed to resolve this inconsistency in familial affiliation.

Many different species of pathogenic fungi cause cranberry fruit rot. The contribution of any given species can be quite variable depending on a host of cultural and environmental factors. Control of fruit rot can be problematic in the Northeast and in other growing regions since losses due to fruit rot can be episodic. One possible cause for inadequate control is that pathogenic fungi typically have differential sensitivity to fungicides. Thus, variation in the species or populations of the fungi present can affect the success and quality of control. Our primary objective in this project was to determine the variation within five species of cranberry fruit rot pathogens (Phyllosticta vaccinii, Coleophoma empetri, Colletotrichum acutatum, Colletotrichum gloeosporioides, and Physalospora vaccinii) across geographic regions [NJ, MA, WI and British Columbia (BC)] using morphologic and molecular characters. Our secondary objective was to reexamine the taxonomy of these pathogens at the molecular level, particularly those that are cranberry- or Vaccinium species-specific. Our results suggest that morphologically, within-species variation was low. We did however collect atypical non-pigmented C. acutatum from BC and Physalospora vaccinii isolates from all regions varied from dark gray to pure white on V8 juice agar medium. Molecular analysis of ribosomal ITS sequences showed a low level of variability for most pathogen species, with the exception of the morphologically distinct isolates. Phylogenetic analysis showed that the atypical, non-chromogenic C. acutatum formed a distinct, but closely related clade, to the normal pink-pigmented isolates. In contrast, the pure white isolates of Physalospora vaccinii possessed an ITS sequence distinct from those of the gray strains, suggesting they may represent a different species.

To evaluate the potential for using postharvest fall floods as a pest management tool, designated sections of several commercial cranberry farms in Southeastern Massachusetts were flooded for 3–4 weeks in September–October. Seeded hibernacula of cranberry fruitworm ( Acrobasis vaccinii ) placed into flooded beds for 3 or 4 weeks had 85% lower moth emergence compared to unflooded beds. Fall flooding may reduce dewberry ( Rubus hispidus ) crown numbers and suppress weed coverage in some situations, but the effects were inconsistent. Fall flooding did not adversely affect percent fruit set, yield, or the new growth of cranberry uprights in the year following the flood. Incorporating fall flooding into commercial farm operations should not be difficult since cranberry growers currently use flooding at other times of year as a standard horticultural practice.

A large number of Gram-negative, motile, mesophilic, violacein-producing bacteria were isolated from the soils and roots of Vaccinium macrocarpon Ait. and Kalmia angustifolia L. plants and from irrigation ponds associated with wild and cultivated cranberry bogs in Massachusetts, USA. Phylogenetic analyses of 16S rRNA gene sequences placed these isolates in a clade with Chromobacterium species, but the specialized environment from which they were isolated, their low genomic DNA relatedness with Chromobacterium violaceum ATCC 12472T and C. subtsugae PRAA4-1T, significant differences in fatty acid composition and colony morphology indicate that the cranberry and Kalmia isolates comprise a separate species of Chromobacterium , for which the name Chromobacterium vaccinii sp. nov. is proposed. Strain MWU205T ( = ATCC BAA-2314T = DSM 25150T) is proposed as the type strain for the novel species. Phenotypic analysis of 26 independent isolates of C. vaccinii sp. nov. indicates that, despite close geographical and biological proximity, there is considerable metabolic diversity among individuals within the population.

An intensive study of the use of spring flooding to control pests and reduce chemical inputs in cranberry production began in 1995, following preliminary studies in 1993 and 1994. This 4-week flood, known as late water (LW), has been shown to suppress some insects, mites, and fungi, and to stimulate plant growth. We demonstrated that pesticide use could be reduced or eliminated in the year of the flood and to a lesser extent in the year following the flood. With the use of LW in from 1993 to 1996, cranberry grower participants in our study reduced insecticide sprays by 24% and reduced fungicide applications by 30% compared to standard practice bogs without effect on crop quality. LW increased mortality of Rubus sp. weeds so that their spread in a cranberry bed was checked. However, the weed population did not decrease over time. Effects of the flood on cranberry growth and productivity were examined. With changes in rate and timing of fertilizer inputs, growth was similar to that on control beds. However, following an abnormally mild winter and drought conditions in 1995, crops on LW bogs were reduced, sometimes severely, compared to the controls. Crop was not affected in 1993, 1994, or 1996. On a LW bog, it is possible to reduce insecticide use by up to 60%, fungicide use by up to 50%, and nitrogen use by 30%. Reductions and outcomes vary depending on seasonal conditions but, with careful management and weather monitoring, this practice remains a strong option for a sustainable cranberry production system.

Little is known about the microscopical symptoms of roots from apple trees suffering from replant disease. Roots were sampled from healthy trees and from such diseased trees in four orchards from May until October. Roots were stained for the detection of mycorrhizal infection and other roots were fixed, dehydrated, embedded in paraffin, sectioned, and stained in safranin and fast green in order to elucidate morphological details. Healthy tree roots possessed considerably higher frequencies of mycorrhizal infection than diseased trees during the entire growing season. Arbuscules and hyphae were very common, vesicles were sometimes present, and possible chlamydospores of Glomus radiatum (Thaxter) Gerd. & Trappe were found in several samples. Whereas roots from healthy trees were structurally intact, roots from declined trees had extensive sloughing away of the epidermal and cortical layers and the cortical cells possessed significant amounts of densely stained material. Nematodes and possible hyphae of Rhizoctonia, Phytophthora, and Pythium were found in roots of declined trees. Althugh the stele of these roots appeared unaltered, hyphae were sometimes observed in the vascular elements.

Decreases in electrical resistance (ER) of tomato taproots were correlated with the progression of Fusarium wilt disease. Production of polygalacturonase (PG) from four isolates of Fusarium oxysporum f. sp. lycopersici, as determined from ammonium sulfate fractions, was correlated with the degree of virulence of each isolate. A drop in ER in tomato plant taproots at 6 cm below the soil level was noticed within 2 h after separate inoculation with all strains. These drops in ER preceded foliar symptom development by 20 h. Measurement of ER in the stems of inoculated tomato plants, however, was found to be no different from that of uninoculated plants. The rate of ER decrease was correlated with the in vitro production of PG by these isolates; the higher the PG activity, the greater the decrease in ER.