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Anthracnose caused by Elsinoë ampelina is one of the most important table grape diseases in humid regions in Brazil and Australia. The objective of this study was to characterize E. ampelina isolates from Brazil and Australia by means of phylogenetic analyses, morphological features and pathogenicity tests. Phylogenetic relationships among 35 isolates were determined based on a data set of internal transcribed spacer (ITS), histone H3 (HIS3) and elongation factor 1‐α (TEF) sequences. In phylogenetic tree analyses, using a combined ITS and TEF sequence alignment, all E. ampelina isolates were clustered together in a single well‐supported clade. In contrast to the absence of genetic variability within ITS and TEF sequences, HIS3 sequences showed 54 polymorphic sites. The haplotype network generated from HIS3 data set showed four distinct haplotypes. EA1 was the predominant haplotype including 29 isolates from both countries. High genetic variability was observed in two Brazilian isolates, haplotype EA4, which may have lost the intron region during species evolution. Colony colours differed between Brazilian and Australian isolates, but showed similar wrinkled colony texture, absence of spores, sparse‐to‐absent white aerial mycelium and slow growth (0.049–0.060 mm/day). Brazilian isolates produced conidia of 5.65 × 2.65 μm, larger than conidia from Australian isolates, which measured 5.14 × 2.30 μm. In pathogenicity tests, all nine Australian isolates inoculated were pathogenic on detached canes and potted vines of table grape.

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Background and Aims: Eutypa dieback is an economically important disease of grapevines and a major threat to vineyard longevity throughout the world. Developing effective preventative strategies offers the best means of control. In this study, pruning wound protectants and various spray applications were evaluated for their ability to prevent infection by ascospores of Eutypa lata. Methods and Results: Fungicides and natural alternative treatments were applied by hand to grapevine pruning wounds in winter prior to inoculation with E. lata. In a series of greenhouse and field experiments, tebuconazole, pyraclostrobin, fluazinam, garlic extract and lactoferrin significantly reduced infection. A range of tractor-driven sprayers was used to apply tebuconazole to pruning wounds, and those which provided good coverage reduced infection by E. lata to a level similar to that when tebuconazole was applied with a paintbrush. Conclusion: Eutypa dieback can be controlled with several fungicides and natural treatments. Tractor-driven sprayers, which by design or modification can efficiently deliver maximum possible coverage at high output rates, can be used for application of pruning wound treatments. Significance of the Study: Results of this study contributed to registration of fungicides for use as pruning wound treatments to control E. lata in Australia. Demonstrating the ability of tractor-driven sprayers to apply treatments effectively has led to greater industry adoption of dormant treatments and may decrease the future impact of Eutypa dieback.

Botryosphaeria dieback, caused by species of Botryosphaeriaceae, is an important grapevine trunk disease in Australia. Inocula produced by the pathogens are primarily dispersed by rain splash and wind and infect pruning wounds leading to cankers, dieback, and eventually death of vines. The objective of this study was to develop molecular tools to detect and quantify Botryosphaeriaceae inocula from the environment. These tools are essential for investigating spore dispersal patterns of Botryosphaeriaceae pathogens in Australian vineyards. DNA extraction protocols were evaluated and one modified protocol was found suitable for extracting Botryosphaeriaceae DNA from artificially and naturally inoculated Burkard volumetric spore sampler tapes. Multispecies primers and a hydrolysis probe for quantitative PCR (qPCR) were further developed to detect and quantify Botryosphaeriaceae inocula from environmental samples. Specificity tests showed that the multispecies primers were able to amplify the DNA of 10 Botryosphaeriaceae species (58 isolates) found in Australia while none of the 27 nontarget fungal species (90 isolates) tested were amplified. The qPCR assay was suitable for amplifying purified DNA, synthetic DNA fragments (gBlocks), and mixed DNA from spore trap tapes. The qPCR method developed in this study was shown to be rapid and sensitive in detecting Botryosphaeriaceae inocula from the environment using spore traps.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is a highly transmissible coronavirus responsible for the pandemic coronavirus disease 2019 (COVID-19), which has had a devastating impact on society. Here, we summarize proteomic research that has helped elucidate hallmark proteins associated with the disease with respect to both short- and long-term diagnosis and prognosis. Additionally, we review the highly variable humoral response associated with COVID-19 and the increased risk of autoimmunity.

The increasing prevalence of the grapevine trunk diseases Eutypa and Botryopshaeria dieback has been attributed, in part, to abiotic stresses imposed on vineyards as production intensifies worldwide. The aim of this study was to evaluate the influence of water deficit irrigation practices on the infection of pruning wounds by Eutypa lata and Diplodia seriata, and the subsequent rate of colonisation. Two vineyard trials were conducted over 2 years in South Australia, one in the Riverland using ‘Cabernet Sauvignon’ with four irrigation treatments (100, 50, 25 and 12.5% of the standard irrigation program) and another in the Barossa Valley using ‘Shiraz’ on six rootstocks and own roots, either irrigated or not irrigated. According to leaf water potential assessments, vines with reduced irrigation were generally in water deficit, and therefore subjected to stress. On the whole, incidence of wound infection and distance of colonisation were similar among irrigation treatments for both pathogens, except in the Riverland, where E. lata colonized canes to a greater extent in well-watered vines than those in water deficit. Only vines on rootstock ‘Ramsey’ in the Barossa Valley had greater extent of colonisation by E. lata in the non-irrigated vines. There was no correlation between internal staining and colonisation, with both pathogens recovered up to nearly 20 cm ahead of the staining. Water deficit did not increase the susceptibility of grapevine pruning wounds to infection, nor colonisation of the subtending tissue by E. lata and D. seriata. In fact, there was evidence of decreased susceptibility to colonisation by E. lata in vines subjected to severe water deficit.

Background and Aims Eutypa and Botryosphaeria dieback are diseases that affect vineyards worldwide, reducing productivity and longevity. The ability of the causal pathogens Eutypa lata and Diplodia seriata to colonise grapevine canes was investigated in the search for resistance or tolerance to trunk diseases. Methods and Results Visual assessments of 174 winegrape cultivars (Vitis vinifera) in a mature germplasm collection in the Barossa Valley in South Australia revealed substantial variation (0–98%) in severity of foliar symptoms and dieback. A selection of 18 cultivars representing those without symptoms or low (<10%) severity was compared with the susceptible cultivars Shiraz and Sauvignon Blanc. Inoculation of canes in situ in the vineyard and detached canes in the greenhouse, confirmed variability among cultivars for the extent of pathogen colonisation. Conclusions Cultivars varied in susceptibility to colonisation by E. lata and D. seriata, with some differences between the two pathogens in terms of the ranking of cultivars. Muscadelle was most resistant to colonisation by both pathogens, and Sauvignonasse was the most susceptible. Significance of the Study Knowledge of cultivar susceptibility to grapevine trunk diseases will assist in prioritisation of disease management strategies. Identification of cultivars with resistance could inform selection of planting material and may lead to improved breeding programs in the future.