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In viticulture, an intensive pesticide schedule is often required to control fungal and oomycete diseases and meet production standards. Accordingly, a reduction of synthetic fungicides and the application of environmentally-friendly crop protection alternatives are becoming increasingly important for a more sustainable viticulture. Even though the adoption of resistant/tolerant varieties is still limited in some traditional grape growing regions, the application of biological and/or physical tools, can in part substitute synthetic fungicides applications, and the use of decision support systems can help in reducing chemical treatments. This chapter presents the state of the art in grapevine protection to reduce pesticide use in viticulture and explores various alternative sustainable management strategies aimed to effectively control grapevine diseases triggered by fungi and oomycetes in nurseries, young and mature vineyards. [ABSTRACT FROM AUTHOR]

The successful implementation of deep learning nets opens up possibilities for various applications in viticulture, including disease detection, plant health monitoring, and grapevine variety identification. With the progressive advancements in the domain of deep learning, further advancements and refinements in the models and datasets can be expected, potentially leading to even more accurate and efficient classification systems for grapevine leaves and beyond. Overall, this research provides valuable insights into the potential of deep learning for agricultural applications and paves the way for future studies in this domain. This work employs a convolutional neural network (CNN)-based architecture to perform grapevine leaf image classification by adapting VGG-16 net and VGG-19 net models and subsequently identifying the optimal performer between the two nets during the classification process. A publicly available dataset comprising 500 images categorized into 5 distinct classes (100 images per class), was utilized in this work. The obtained empirical outcomes demonstrate a remarkable accuracy rate of 99.6% for the VGG-16 net model, while VGG-19 net achieves a 100% accuracy rate. Based on these findings, it can be inferred that VGG-19 net exhibits superior performance in classifying images of grapevine leaves compared to the VGG-16 net. [ABSTRACT FROM AUTHOR]

Esca is a grapevine trunk disease (GTD) that is caused by filamentous fungi. It is responsible for considerable economic losses in viniculture on a global scale. Despite many unknown factors contributing to the development of symptoms in affected plants, Phaeoacremonium minimum (PMI), Phaeomoniella chlamydospora (PCH) and Fomitiporia mediterranea (FMED) are generally considered as the main causative fungal species. Early detection and specific identification of these pathogens therefore play an important role in disease control and evaluation of suitable countermeasures. In this study, loop‐mediated isothermal amplification (LAMP) assays were developed for each of the three pathogens. A genome‐based approach was applied for detection and selection of unique target DNA sequences. The designed primer sets showed overall good specificities, with some observed cross‐reactions towards closely related Phaeoacremonium species for the PMI primer set. The developed assays had detection limits of 100 pg (FMED, PMI) and 1 pg (PCH) per reaction (corresponding to 1460 [FMED]; 1950 [PMI]; 342 [PCH] genome copies per reaction). The application of the assays to field samples was demonstrated by testing individual infected grapevine trunks from two European viticultural regions using crude DNA obtained in a rapid sample preparation step. LAMP assay results matched those of PCR following a conventional DNA extraction protocol. The study showed that LAMP‐based rapid molecular detection of major Esca agents can serve as a useful tool for further research and surveillance of a highly devastating grapevine disease. The application of computer‐based whole genome comparison between target and non‐target species for the identification of unique target sequences as the basis for LAMP (or PCR) primer design was demonstrated to be a useful approach in species for which scarce sequence information is available. Moreover, the developed method for rapid DNA preparation from grapevine trunks may potentially be adapted to the DNA‐based detection also of other fungal species that cause grapevine trunk diseases. [ABSTRACT FROM AUTHOR]

'Bois noir' (BN) and flavescence dorèe (FD), the two main diseases of the grapevine yellows complex associated with genetically distinct phytoplasmas, have a complex epidemiology including multiple insect vectors and reservoir plants. This study investigated the presence of BN and FD phytoplasmas in nine groundcover plant species commonly utilized for inter-row vineyard green manure in Franciacorta (North Italy). The activities conducted in 2020 included monitoring and sampling groundcover plant species and symptomatic grapevines in September, and phytoplasma identification and typing by amplification and sequence analyses of stamp and map genes. Molecular analyses identified BN phytoplasma (strains carrying the stamp gene sequence variants St5, St19, St30) and FD phytoplasma (strains carrying the map gene sequence variant M54) in 72% and 28% of symptomatic grapevines, respectively. BN phytoplasma strains St5 and St30 were found also in Eruca sativa, Vicia sativa, and Polygonum fagopyrum. FD phytoplasma strain M54 was found also in Vicia faba, Trifolium incarnatum, and Polygonum fagopyrum. These results reinforced the evidence of the increasing range of BN and FD phytoplasma alternative plant hosts and suggested a criterium for the selection of the groundcover plant species utilized for green manure, excluding the ones putatively involved in BN and FD diffusion. [ABSTRACT FROM AUTHOR]

Grapevine trunk diseases (GTDs) are currently among the most important health challenges for viticulture in the world. Esca, Botryosphaeria dieback, and Eutypa dieback are the most current GTDs caused by fungi in mature vineyards. Their incidence has increased over the last two decades, mainly after the ban of sodium arsenate, carbendazim, and benomyl in the early 2000s. Since then, considerable efforts have been made to find alternative approaches to manage these diseases and limit their propagation. Biocontrol is a sustainable approach to fight against GTD-associated fungi and several microbiological control agents have been tested against at least one of the pathogens involved in these diseases. In this review, we provide an overview of the pathogens responsible, the various potential biocontrol microorganisms selected and used, and their origins, mechanisms of action, and efficiency in various experiments carried out in vitro, in greenhouses, and/or in vineyards. Lastly, we discuss the advantages and limitations of these approaches to protect grapevines against GTDs, as well as the future perspectives for their improvement. [ABSTRACT FROM AUTHOR]

Flavescence dorée phytoplasma (FDp) is a great threat to grapevine cultivation in Europe. Severe symptoms induced by FDp in grapevine plants, along with side effects of insecticide treatments used to control disease spread, bring considerable economic and environmental toll and challenge the sustainability of European viticulture. Previous research of map gene sequences identified three genetic clusters of FDp – Map-FD1, -FD2 and -FD3. Each cluster is affiliated with different geographical distribution and characterized by different genetic variability and epidemiological properties. Those clusters are identified through laborious and time consuming nested PCR-RFLP or sequencing and phylogenetic analysis. Here, a multiplex real-time PCR assay was developed for rapid and sensitive detection of the three FDp genetic clusters by using a single primer pair and three distinct BHQ probes labelled with different fluorescent dyes. The assay was evaluated using FDp reference strains, phytoplasma strains belonging to different phytoplasma groups and field collected FDp isolates. The assay was found to be highly sensitive and reliably detected and discriminated all three Map-FD genetic clusters within the 16Sr-V phytoplasma group. Early detection of Map-FD genetic clusters and thus phytoplasma genotypes which are less likely to cause epidemic outbreaks due to different transmission pathways, can significantly accelerate FDp epidemiological studies and facilitate the efforts to control the FD disease. [ABSTRACT FROM AUTHOR]

Vitis vinifera L. is a plant species that depends highly on temperature and water availability. Excessively hot and dry conditions can undermine growth and threaten grapevine performance. In these situations, grapevines activate self-regulating mechanisms to respond to water stress by prioritizing their survival through stomatal control and water redistribution. The monitoring of these mechanisms, through the measurements of the trunk diameter fluctuations and sap flow, was made for ‘Touriga-Nacional’ planted in the Douro Demarcated Region (NE Portugal), during the 2017 growing season. Seasonal and trend decomposition of the acquired data, as well as the assessment of the potential influence of meteorological variables was carried out, using locally estimated weighted regression and scatterplot smoothing. The objective behind this decomposition was to assess if the individual analysis of the periodic and inter-daily variations of the grapevine's trunk diameter fluctuations and sap flow could improve the understanding of their response to abiotic stress. The results have shown the methodology is efficient in extracting the different components and that their analysis is informative. It was possible to determine that the delay between the daily trunk diameter and sap flow periodic variations became shorter in time, suggesting the loss of water by transpiration is more easily observable under increasingly hotter and drier conditions. Furthermore, longerterm, inter-daily variations at the trunk are highly correlated with those of relative humidity, evidencing the impact of air moisture on their water status. Such findings justify the implementation of locally weighted regression and scatterplot smoothing (STL) in the operational processing of sap flow and trunk diameter time series in the control of grapevine water status, in the case of optimization of vineyard management by wine growers. [ABSTRACT FROM AUTHOR]

Grapevine crown gall (GCG), which is caused by tumorigenic Allorhizobium vitis (=Rhizobium vitis), is the most important bacterial disease in grapevine, and its economic impact on grapevine is very high. When young vines develop GCG, they often die, whereas older vines may show stress and poor growth depending on the severity of GCG, because GCG interferes with the vascular system of the grapevine trunk and prevents nutrient flow, leading to inferior growth and death. Viticultural practices and chemical control designed to inhibit GCG are only partially effective presently; thus, a biocontrol procedure could be a desirable and effective approach for GCG prevention. This article reviews the practical use of biocontrol options for GCG inhibition that involve using nonpathogenic and antagonistic A. vitis strains. In these studies, screening tests of biocontrol agents discovered nonpathogenic A. vitis strains VAR03-1, ARK-1, ARK-2, and ARK-3. After dipping grapevine roots in a suspension of candidate strains prior to planting in the field, treatment using ARK-1 was shown to significantly reduce the number of plants with GCG. A meta-analysis indicated that ARK-1 is very useful for controlling crown gall in various plant species, including grapevine. It was reported that when a mixture of ARK-1 and a tumorigenic strain was examined in grapevines, the expression levels of several virulence genes of the virulent strain were significantly lower. ARK-1 can reduce the pathogen population in grapevines and gall incidence. Moreover, ARK-1 can prime the induction of certain defense genes of grapevine. These results indicate that ARK-1 has a unique biocontrol mechanism and that it is a promising new biocontrol agent to control GCG. [ABSTRACT FROM AUTHOR]

Chitosan is a biopolymer with various favorable properties (biotic/abiotic stress mitigation, qualitative improvement, bio-fertilizer, bio-stimulant and postharvest management) to meet multiple agricultural objectives. Grapevine is an important crop and has an enormous impact on the world's economy due to its derived products, notably the different wine styles. In viticulture, chitosan application made significant developments towards higher contents of beneficial metabolites in grape berries as well as stress and postharvest management during recent decades, although the reports are limited. Recent investigations by our group demonstrated chitosan as a potential elicitor molecule at a molecular level and opened the possibility to use chitosan for trunk disease management; moreover, there are not yet any methods to combat trunk diseases in grapevine. The present viewpoint aimed to summarize the different aspects of chitosan application in grapevine in facilitating the development of inclusive and more integrated sanitary viticulture practices in a sustainable manner. [ABSTRACT FROM AUTHOR]

Powdery mildew is an economic threat for viticulture because it not only affects grape yield, but also causes a series of impacts on the qualities of fruit and wine, especially the flavors and various metabolites. Different grape varieties may have different levels of powdery mildew resistance/tolerance and their components of their metabolome are also various. In this study, two wine grape varieties, Guipu No.6 (GP6) and Marselan (Mar) with different levels of powdery mildew tolerance, were used to compare the quality differences in metabolism level by using the widely targeted metabolomics method. The results show that GP6 has a better powdery mildew leaf tolerance than Mar. A total of 774 metabolites were detected by using a UPLC-QQQ-MS-based metabolomics approach, and 57 differential metabolites were identified as key metabolites that were accumulated after infection with powdery mildew in GP6 and Mar, including phenolic acids, flavonoids, terpenoids, stilbenes, lipids, nucleotides and derivatives, lignans and coumarins, and quinones. This finding indicates that the defense mechanisms of grape fruit are mainly associated with phenylpropane-flavonoid metabolism. Specifically, stilbenes had greater variations after powdery mildew infection in GP6; while in Mar, the variations of flavonoids, especially kaempferol-3-O-glucuronide and luteolin-7-O-glucuronide, were more remarkable. The above results demonstrate that stilbenes may play a more important role than flavonoids in resisting powdery mildew infection in GP6's fruits, and the drastic variations of these phenolic compounds in different wine grapes after powdery mildew infection might also lead to quality difference in the flavors. This study can provide new insights into the understanding of the cause of powdery mildew tolerance in different grape varieties and the effects on the quality of wine grapes infected with the disease exerted by metabolism level. [ABSTRACT FROM AUTHOR]

Grapevine trunk diseases threaten wine and table grape production worldwide, primarily by reducing yields and, in its advanced stages, causing plant death. Among those diseases, the complex etiology disease known as hoja de malvón (HDM) significantly concerns Argentinian and Uruguayan viticulture. At least four different fungi are associated with this disease, but their role and interactions with other wood microorganisms are understudied. In this sense, analyzing grapevine wood microbiome composition could help understand microbial interactions occurring in HDM onset. Hence, a metatranscriptomic study was performed for the microbiome characterization of mature field-grown Vitis vinifera cv. Malbec, leaf-symptomatic or leaf-asymptomatic. The microbiome was mainly represented by Dothideomycetes and Actinobacteria. In the plant with more marked symptoms, higher levels of the Basidiomycota Arambarria destruens and Phellinus laevigatus were detected. Despite this particular difference, discriminating symptomatic from asymptomatic plants based on the presence or abundance of HDM pathogens was not possible. Alpha diversity and rank-abundance curve analyses indicated that plants with foliar symptoms have lower microbial evenness than asymptomatic plants. The co-occurrence network modeled microbial interkingdom interactions. Molecular data generated in this study will help develop future targeted molecular quantification for specific taxa. [ABSTRACT FROM AUTHOR]

The excessive use of copper-based agrochemicals poses a serious concern to viticulture worldwide. As a consequence, vineyard soil can become contaminated, leading to reduced vine growth and increased susceptibility to soilborne pathogens. Black foot, caused by various pathogenic species, including Dactylonectria macrodidyma , is a fungal disease that impacts the trunk and roots of vines. Enhancing plant biomass and productivity can involve various strategies, such as utilizing beneficial bacteria immobilized in biochar. This study aimed to investigate the impact of applying biochars derived from grape bagasse and enriched with Bacillus velezensis S26 endospores on alleviating copper stress, controlling black foot disease, and promoting the growth of the vine rootstock SO4 (Vitis berlandieri × V. riparia). Initially, we assessed various methods for immobilizing bacterial endospores into fresh bagasse biochar (FBB) and composted bagasse biochar (CBB). Subsequently, the cell viability of incorporated B. velezensis S26 endospores was evaluated over a 180-day storage at 4 and 25 °C. Finally, a pot experiment was conducted using micropropagated SO4 plants to investigate the growth-promotion capacity and biocontrol potential of both biochar and biochar enriched with B. velezensis S26 endospores. Our findings revealed that refrigerated storage ensured the highest cell viability in CBB, while no statistically significant difference was observed among the evaluated treatments for FBB. The application of B. velezensis S26 endospores, FBB, and CBB, either as a single inoculation or combined treatments, resulted in increased plant growth measurements. In addition, both FBB and CBB enriched with B. velezensis S26 endospores enhanced the growth and biomass of SO4 rootstocks cultivated in substrates with high copper concentrations or inoculated with D. macrodidyma TD1110. Furthermore, the frequency of pathogen re-isolation decreased by 29 % and 31.5 % using fresh and composted grape bagasse biochars enriched with bacterial endospores, respectively. Therefore, the utilization of fresh and composted bagasse biochars not only contributed to improving rootstock development measurements and suppressing the effects of D. macrodidyma TD1110 in SO4 vine rootstocks but also to waste valorization and a more sustainable agriculture. [Display omitted] • Low storage temperatures preserve endospore viability in fresh bagasse biochar. • Chemical treatments did not improve endospore immobilization into biochars. • Grape bagasse biochar loaded with B. velezensis S26 endospores enhances vine growth. • Fresh and composted bagasse biochars alleviate copper stress in SO4 rootstock. • Fresh and composted bagasse biochars suppress black foot in SO4 rootstock. [ABSTRACT FROM AUTHOR]

The European grape berry moth, Eupoecilia ambiguella (Hübner) (Lepidoptera: Tortricidae), since its first identification in 1796, was defined as a key pest for European viticulture despite its polyphagy. Although between the late 1800s and early 1900s its presence and spread in Europe was of concern, to date its populations are low and limited to cooler and wetter areas, leading to a decline in its importance. In the present work, we reviewed its global distribution as well as its morphology, biology, and ecology. Considering the monitoring and management of this pest, the present review summarised insecticidal, agronomic, and cultural control strategies. Moreover, given the need to reduce the impact of agriculture on the environment, humans, and non-target species, we focused on control strategies relying on pheromones and biological control agents (e.g. predators and parasitoids) involved in conservation biological control. • The European grape berry moth, Eupoecilia ambiguella , has a long history as grape pest. • We reviewed knowledge on its morphology, bio-ecology, and geographical distribution. • Current monitoring and management tools were discussed. • Potential biocontrol agents were extensively reviewed. • Challenges for E. ambiguella IPM and biological control were formulated. [ABSTRACT FROM AUTHOR]

Pest management strategies relying on agrochemicals could be altered by climate change, because of the temperature-dependent toxicity of the compound involved. Many studies have explored the response of targeted pests to pesticide and temperature. Pesticides are seldom strictly selective and also affect nontarget pests. Surprisingly, the way temperature may shape these side effects of pesticides remains overlooked, limiting our understanding of the net impacts of future chemical treatments on the overall damage induced by different pests. We investigated how temperature modulates the response of a major grape insect pest (the tortricid moth Lobesia botrana) to a copper-based fungicide. We examined the lethal (larval survival) and sublethal (larval development, pupal mass, immune parameters) effects of exposure to different concentrations of copper in larval food. We found that copper concentration had negative linear effects on larval development and pupal mass. In addition, copper concentration had biphasic curvilinear effects on total phenoloxidase activity, which is indicative of hormesis (stimulation and inhibition of insect performance at low and high copper concentrations, respectively). Temperature stimulated development, while compromising immunity (total phenoloxidase activity). Significant interaction between copper concentration and temperature was detected for larval survival and phenoloxidase activity: warmer conditions improved pest tolerance to copper through temperature-driven hormesis (larval survival) or by shifting the hormesis-related peak of performance toward higher copper concentrations (phenoloxidase activity). This combination of simple and interactive effects could propagate to populations, communities and agroecosystem, with implications for future management of viticultural pests. [ABSTRACT FROM AUTHOR]

Paralobesia viteana (Clemens), grape berry moth, is a major pest of grapes in Eastern North America. There is substantial regional variation in the response of male P. viteana to sex pheromone-baited monitoring traps in Michigan vineyards. Males are readily captured in traps in the southwest region, whereas in the northwest very few males are captured, despite larval infestation in grapes in both regions. Y-tube olfactometers and field experiments determined the response of male moths from northern and southern populations to the pheromone blend used in monitoring lures and to females from both regions. In Y-tube choice tests, males responded similarly to the standard pheromone blend, and males did not preferentially choose females from either region. In field trials, traps baited with unmated females were deployed to test the preference of resident males for females from the two regions and for standard pheromone lures. In southwest Michigan vineyards, significantly more males were caught in traps with a 1.0-µg standard pheromone lure than in traps with captive females collected from vineyards in both regions or in traps with a blank lure control. A similar pattern of male captures among lure treatments was observed in northwest vineyards, although many fewer males were trapped and differences among treatments were not significant. We conclude that the observed regional differences in male response to pheromone traps are not caused by variation in pheromone-mediated behavioral responses, suggesting that other biotic and/or abiotic differences determine the regional variation in captures of this species. [ABSTRACT FROM AUTHOR]

The vine mealybug (VMB), Planococcus ficus, is a major grapevine pest worldwide, whose chemical control is often unsatisfactory due to its cryptic behavior, insecticide resistance and high fecundity rate. Recently, increasing restrictions have been applied to insecticides used for managing VMB. This review discusses sustainable VMB management strategies in organic viticulture. Pheromone-mediated mating disruption has been proved to be effective in both organic wine and table-grape vineyards. Biocontrol projects carried out through the release of parasitoids and/or predators have often provided inconclusive results, ranging from effective reduction of mealybug infestation to a marginal impact of parasitoids on VMB density. The latter outcome is likely due to constraints affecting the parasitoid activity, such as the disrupting activity of mealybug-tending ants and broad-spectrum insecticides, or untimely release of parasitoids. Ant suppression should be associated with the release of beneficial organisms, as mealybug-tending ants can severely affect the parasitoid activity. Cultural and physical control and the employment of entomopathogens and natural products mitigate the buildup of VMB populations, but they are not widely applied. VMB control in organic viticulture requires the integration of different strategies, as application of single control tools as a stand-alone treatment may not be effective, especially for high pest infestation. Future research to determine the density action threshold below which sustainable methods are effective and calibrate efforts in relation with pest infestation is needed. A multi-disciplinary approach is required to define the most appropriate sustainable control protocols in different environmental conditions and promote a further spread of organic viticulture. [ABSTRACT FROM AUTHOR]

Diversity and community structure of soil microorganisms are increasingly recognized as important contributors to sustainable agriculture and plant health. In viticulture, grapevine scion cultivars are grafted onto rootstocks to reduce the incidence of the grapevine pest phylloxera. However, it is unknown to what extent this practice influences root-associated microbial communities. A field survey of bacteria in soil surrounding the roots (rhizosphere) of 4 cultivars × 4 rootstock combinations was conducted to determine whether rootstock and cultivar genotypes are important drivers of rhizosphere community diversity and composition. Differences in α-diversity was highly dependent on rootstock–cultivar combinations, while bacterial community structure primarily clustered according to cultivar differences, followed by differences in rootstocks. Twenty-four bacterial indicator genera were significantly more abundant in one or more cultivars, while only thirteen were found to be specifically associated with one or more rootstock genotypes, but there was little overlap between cultivar and rootstock indicator genera. Bacterial diversity in grafted grapevines was affected by both cultivar and rootstock identity, but this effect was dependent on which diversity measure was being examined (i.e., α- or β-diversity) and specific rootstock–cultivar combinations. These findings could have functional implications, for instance, if specific combinations varied in their ability to attract beneficial microbial taxa which can control pathogens and/or assist plant performance. [ABSTRACT FROM AUTHOR]

Botrytis cinerea, the grey mould agent, is one of the most important pathogens of grapevine, due to the great yield losses caused and the economic costs related to disease control. Ground cover plants are assumed to have a role in the complex epidemiology of the pathogen, even if no information on the genetic variability of the strains is available. In this study, a molecular epidemiology approach, based on the comparative analysis of the nucleotide sequences of multiple genes (ITS1‐ITS2, G3PDH, NEP1, NEP2, BC‐hch, and sdhB), was used to evaluate whether B. cinerea isolated from herbaceous species contributes to grey mould diffusion on grapevines. From 330 samples collected in two vineyards in Lombardy, Italy, 63 B. cinerea strains were isolated from tissues of grapevine with symptoms (50 strains) and spontaneous ground cover plants (13 strains). Capsella bursa‐pastoris, Cardamine impatiens, Lamium purpureum, and Crepis tectorum were identified as novel B. cinerea hosts. Sequence analysis and phylogeny showed that the same genotypes were present on both grapevines and herbaceous plants, with no fitness (estimated from growth and sporulation on potato dextrose agar) or pathogenicity (on grapevine leaves and berries, and tomato leaves) penalties. This confirms that ground cover plants can be a source of inoculum for B. cinerea on grapevine. Moreover, phylogenetic analysis of the BC‐hch gene allowed the identification of two genetically distinct clusters, characterized by vegetative incompatibility and different distributions of the mating types, fitness, and pathogenicity. Therefore, B. cinerea seems to be composed of two diverging subpopulations that do not differ for host specialization. [ABSTRACT FROM AUTHOR]

Copyright of Glasnik Zastite Bilja is the property of Zadruzna Stampa D.D. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Viticulture is one of the most important crop industries in the world and its cultivation is on the upward trend globally. Global water and soil resources continued to decline sharply and rampant extreme weather conditions are becoming a serious threat to sustainable agriculture and food security. Further, the changes in climatic conditions are increasingly becoming favorable for rearing certain harmful biotic organisms, which are hostile to sustained grape cultivation. The environmental changes have shown a projected negative impact on viticulture by increased biotic and abiotic stresses. Range of strategies can be employed to mitigate such scenarios, however, integration of rootstocks to combat such challenges is a sustainable nature. Grape rootstocks have exhibited their role in mitigating the problems raised due to a variety of environmental stresses. For example, certain Vitis species are used as rootstock against phylloxera and other harmful pests of grapes. Similarly, there are certain rootstocks developed which have their tolerance against salinity, drought, cold, and iron chlorosis. With ever-changing environmental conditions, it is not essential that one rootstock perfors better at a specific place may perform well in another place. This article reviewed several grape rootstocks which have their specific resistance or tolerance features against a variety of stresses, including pests, disease, salinity, and drought. Consistent endeavors in grapevine rootstock improvement and utilization are critical for the sustainability of the grape industry, in particular during the ever-increasing environmental stresses. [ABSTRACT FROM AUTHOR]

Grapevine trunk diseases (GTDs) are among the most severe problems in viticulture worldwide. The exact etiology and the role of endophytic microorganisms is not known yet and there is no adequate protection or curative treatment against the disease. Hungarian wine regions are also affected by the disease, and there is restricted information about the rate of infection nation-wide and about the susceptibility of the Hungarian cultivars. The main objectives of our research are to measure the symptom expression and the damage caused by GTDs, to understand the epidemiology and etiology of the disease to establish a foundation of a proper disease management. Cultivar susceptibility groups were created with the aim to allocate some Hungarian cultivars and the role of vineyard age was also examined in symptom expression. [ABSTRACT FROM AUTHOR]

Three rootstock mother blocks, planted with cultivars SO4 (planted 2004), 125AA (2005) and 5BB (2005), and located in southwestern Germany were examined for the existence of grapevine trunk disease (GTD) pathogens and related internal and external symptoms between 2011 and 2017. Frequency of leaf symptoms ranged from 0.2% in six-year old blocks to appr. 1.5% in 12-year-old blocks. While the typical "tiger stripe pattern" was less common, the majority of affected leaves was characterized by irregularly arranged necrotic spots spread over the leaf surface. Irrespective of leaf symptoms, in cross sections of 9-12 year old vines all sampled trunks (n ≥ 20 for each block) showed the typical GTD symptoms in the wood, with symptoms prevalent in the trunk head compared to the middle section and the basis of trunks. Pathogens were isolated from all trunks, with Fomitiporia mediterranea (Fmed), Cadophora luteo-olivacea (Clo), Phaeomoniella chlamydospora (Pch), Eutypa lata (Elata), and Phaeoacremonium aleophilum (Pal) being the most common. Other GTD species included Cadophora cf. novi-eboraci (new for German viticulture), Diaporthe eres, D. nobilis (new for German viticulture), D. rudis (new for German viticulture), Eutypa laevata (new for German viticiculture), Ilyonectria europaea, I. liriodendri, and Pestalotiopsis sp. The significance of the once found Sarocladium strictum remains unclear. GTD species were revealed from all sampled trunk parts, with maximum diversity and overall frequency in the trunk head. Further species, not related to GTDs, existed in all parts of the trunk. GTD pathogens were also demonstrated for all shoots (two shoots each of ten vines SO4, 125AA and 5BB, with five vines each externally symptomatic and non-symptomatic), but mostly could be detected by molecular means only. Clo, Pch, and Pal were the predominant species in shoots; further GTD species were Ilyonectria europaea, I. liriodendri, and Phaeoacremonium angustius. [ABSTRACT FROM AUTHOR]

Black foot disease of grapevines is a major economic issue for the viticulture industry, with several Dactylonectria and Ilyonectria species identified as causal agents worldwide. This study aimed to confirm the pathogenicity of an Ilyonectria pseudodestructans isolate recovered from a symptomatic grapevine in a nationwide survey. An initial pot experiment inoculated callused and root-wounded grapevine propagation material of varieties '101- 14' and '5C' with I. pseudodestructans conidia. The second pot experiment compared the pathogenicity of I. pseudodestructans conidial, chlamydospore and mycelial inocula. Disease incidence, severity and root and shoot dry weights were determined after 4-5 months of growth. Ilyonectria pseudodestructans was recovered from inoculated plants resulting in higher disease incidence and severity compared with the uninoculated control. Disease severity and incidence was higher for callused compared to rooted propagation material, but did not differ between grapevine varieties. Conidial inoculum caused greater disease incidence and severity compared with chlamydospore and mycelial inocula. Ilyonectria pseudodestructans propagules infected grapevine plant material via the callused basal ends or wounded roots, indicating this species is a potentially important pathogen of grapevines both in nurseries and vineyards. [ABSTRACT FROM AUTHOR]

Since the early 1990s, grapevine trunk diseases (GTDs) have posed threats for viticulture. Esca complex, Eutypa- and Botryosphaeria- diebacks, mostly detected in adult vineyards, are currently responsible for considerable economic losses in the main vine-growing areas of the world. Other GTDs, such as Petri- (Esca complex) and Black-foot diseases, are emerging problems in grapevine nurseries (resulting in grafting failures and/or loss of saleable plants) and in young vineyards. The impacts of GTDs in modern viticulture depend on several factors, some related to their complexity, and others linked to host plant characteristics, changes in vineyard management and to the scarcity of simple tools for their control. For these reasons control of GTDs remains difficult, also depending on knowledge transfer from research to field and vice versa. This paper outlines the main preventive and curative techniques currently applied, scientifically tested or not that have resulted from the outcomes of "Winetwork", a European Union funded project with special emphasis on the promising and innovative approaches. [ABSTRACT FROM AUTHOR]

Copyright of Glasnik Zastite Bilja is the property of Zadruzna Stampa D.D. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Grapevine is one of the most widely grown fruit crops in the world. At present, however, there is much concern regarding chemical pollution in viticulture due to the application of chemical fungicides and fertilizers. One viticultural practice to resolve this issue is the application of micro‐organisms to grapevine as a substitute for chemicals. Some micro‐organisms act as an enhancer of grape berry quality as well as a suppresser of disease in grapevine through their antagonistic ability and/or systemic resistance inducing ability. Herein, we review current and prospective applications of micro‐organisms in viticulture. Significance and Impact of the Study: In this review, we evaluate the applicability of micro‐organisms in viticulture. Micro‐organisms can improve grape berry quality through grapevine disease protection and grape berry quality alteration. Because the use of micro‐organisms to protect grapevine from plant diseases is safer than the use of chemical fungicides, the use of biofungicides in viticulture is expected to be enhanced by the increasing consumer concern towards chemical fungicides. Micro‐organisms also modify plant secondary metabolites for use as flavours, pharmaceuticals and food additives. Studies of micro‐organisms that promote polyphenol, anthocyanin and aroma compound biosynthesis are in progress with an eye to improving grape berry quality. [ABSTRACT FROM AUTHOR]

Research on the spread of nepoviruses - Grapevine fanleaf virus GFLV and Arabis mosaic virus (ArMV) have been performed at several grape growing farms in the Rahovec municipality. In this area are sampled varieties: Afuzali, Demirkapi, Groqanka, Melnik, Pllovdin, Prokupe, Smederev, Vranac, Game, Italian Rizling and Zhillavk. According to ELISA test results, from 165 grape samples in Rahovec municipality tested by the ELISA method for nepoviruses - Grapevine fanleaf virus GFLV and Arabis mosaic virus ArMV, (1%) are infected with Arabis mosaic virus ArMV and (2.7%) are infected with Grapevine fanleaf virus GFLV. [ABSTRACT FROM AUTHOR]

Viticulture has experienced dramatic global growth in acreage and value. As the international exchange of goods has increased, so too has the market demand for sustainably produced products. Both elements redefine the entomological challenges posed to viticulture and have stimulated significant advances in arthropod pest control programs. Vineyard managers on all continents are increasingly combating invasive species, resulting in the adoption of novel insecticides, semiochemicals, and molecular tools to support sustainable viticulture. At the local level, vineyard management practices consider factors such as the surrounding natural ecosystem, risk to fish populations, and air quality. Coordinated multinational responses to pest invasion have been highly effective and have, for example, resulted in eradication of the moth Lobesia botrana from California vineyards, a pest found in 2009 and eradicated by 2016. At the global level, the shared pests and solutions for their suppression will play an increasing role in delivering internationally sensitive pest management programs that respond to invasive pests, climate change, novel vector and pathogen relationships, and pesticide restrictions. [ABSTRACT FROM AUTHOR]

This paper presents the The researches took place at the Bujoru Vine-Growing Research and Development Stage in 1992-2016 and targeted the spread of the main pathogens and pests in the vineyard plantations, an ecological phenomenon that is influenced by ecological zonal factors and ecological plasticity, each species occurs in nature on a given territory occupying a determined area. After analyzing the dynamics of the vineyard health status of the Bujoru viticulture ecosystem in the last 25 years, it is observed that the occurrence and evolution of the main pathogens were influenced by the climatic conditions area. In the vineyard plantations of the Bujoru vineyard, harmful fauna is relatively varied and numerous, but only a few pathogens (manna, mildew, gray rot) produce year-on-year significant economic damage. Pathogens were monitored by notaries observations and scores to determine the frequency (F), intensity (I) and attack rate (G.A %). [ABSTRACT FROM AUTHOR]

This study was conducted in several farms in Rahovec, Suhareka and Prizren municipalities where viniculture is developed. The following samples of varieties were selected in above mentioned regions: Afuzali, Demirkapi, Groqanka, Melnik, Pllovdin, Prokupe, Smedereve, Vranac and Zhillavk. In Rahovec region a total of 155 samples were selected, followed by the Suhareka region with 90 samples and Prizren region with a total of 5 samples. In August (2014) the labelling of samples and observation of symptoms were conducted and in January (2015) sample collection was carried out, whereas in April (2015) all samples were tested with ELISA method. All samples (300) were tested for seven viruses: Nepoviruses: (GFLV, ArMV), Closterovirus: (GLRaV-2), Ampeloviruses: (GLRaV-1, GLRaV-3), Vitivirus: (GVB) and Vitivirus: (GVA). According to the results of the ELISA test, GLRaV-3 is the most common virus with (13.3%). The second most common virus is GLRaV-1 with (8%), followed by GVA (7.3%). Regarding GFLV (2.3%) and ArMV (1%), these viruses were detected with very low incidence. None of the tested samples gave any positive reaction to GLRaV -2 and GVB. In respect of the virus distribution based on regionalization, out of 125 samples selected in Rahovec 44% came up with a positive result and out of 95 samples in Suhareka 38 were infected, whereas in Prizren only 1% samples out of 40 samples were infected. [ABSTRACT FROM AUTHOR]

Improving natural pest control by promoting high densities of predatory mites (Acari: Phytoseiidae) is an effective way to prevent damage by pest mites (e.g., Eriophyidae, Tetranychidae) and other arthropod taxa that can cause serious damage to vineyards. Here, we investigate the influence of innovative management on predatory mite densities. We compare (i) full versus reduced fungicide applications and (ii)minimal pruning versus a traditional trellis pruning systemin four fungus-resistant grapevine varieties. As predatory mites also feed on fungus mycelium, we assessed fungal infection of grapevine leaves in the experimental vineyard. Predatory mites were significantly more abundant in both minimal pruning and under reduced plant protection. Increases in predatory mites appeared to be independent of fungal infection, suggesting mostly direct effects of reduced fungicides and minimal pruning. In contrast to predatory mites, pest mites did not increase under innovative management. Thus, conditions for natural pest control are improved in fungus-resistant grapevines and underminimal pruning, which adds to other advantages such as environmental safety and reduced production cost. [ABSTRACT FROM AUTHOR]

Grapevine Pinot gris virus (GPGV) was identified in several grapevine cultivars, particularly in cv 'Vermentino' showing leaf mottling and deformation, in the Sardinia and Lazio regions of Italy. The majority of GPGV-infected cultivars were asymptomatic but the virus was not detected in samples from vineyards older than 10 years and/or planted with local cultivars, confirming the recent introduction of the virus in these two regions likely through the distribution and use of infected propagation material. Similar to reports from other regions, the high incidence of GPGV in asymptomatic vines is creating challenges with regard to control. [ABSTRACT FROM AUTHOR]

In most vineyards worldwide, agents of grapevine trunk diseases represent a real threat for viticulture and are responsible for significant economic loss to the wine industry. The conventional microbiological isolation technique used to diagnose this disease is tedious and frequently leads to false negatives. Thus, a dire need exists for an alternative method to detect this disease. One possible way involves infrared spectroscopy, which is a rapid, nondestructive analytical tool that is commonly used for quality control of feed stuffs. In the present work, a midinfrared spectrometer was tested as a fast tool for detecting agents of grapevine trunk disease. Midinfrared spectra were collected from 70 Vitis vinifera L. cv. Cabernet-Sauvignon one year old trunk-wood samples that were infected naturally in one viticulture nursery of the south of France. The samples underwent polymerase chain reaction and morphological identification, and the results were correlated to the midinfrared spectra by using multivariate analysis to discriminate between noninfected and infected samples. Based on comparison with some control samples, the highest percentage of correct identification of fungal contamination when using the midinfrared spectroscopy method is 80%. [ABSTRACT FROM AUTHOR]

Thirteen species of lesser known wood inhabiting fungi living on grapevine (Vitis vinifera) and/or in the vicinity of vineyards are presented with respect to systematics, life strategy and symptoms, host range, geographic distribution, transmission and occurrence on Vitis, identification, and diagnosis. Sampling has been performed during a three-year-survey covering nurseries, vineyards, and neighboring fruit trees in the viticultural area of southern Palatinate, Germany. The possible pathogenic significance and the relation to grapevine trunk diseases are discussed. The following species are reported for the first time in Germany: Cadophora luteo-olivacea, C. fastigiata, Collophora paarla, Coniochaeta hoffmannii, Eucasphaeria capensis, Phomopsis cotoneastri, and the Esca-related Phaeoacremonium viticola and P. fraxinopennsylvannicum. Eucasphaeria capensis and Phomopsis cotoneastri are reported for the first time from Vitis worldwide. [ABSTRACT FROM AUTHOR]

Mealybugs (Hemiptera: Pseudococcidae) represent a serious threat for viticulture as vectors of phloem-restricted viruses associated with the grapevine rugose wood and leafroll diseases. Heliococcus bohemicus (Šulc) is known to be involved in the spread of these two viral diseases, being a vector of the Grapevine virus A (GVA) and the Grapevine leafroll-associated virus 1 and 3 (GLRaV-1 and GLRaV-3). This study investigated the acquisition and transmission efficiency of H. bohemicus fed on mixed-infected plants. Nymphs were field-collected onto GVA, GLRaV-1, and GLRaV-3 multiple-infected grapevines in two vineyards in North-Western Italy, and were used in transmission experiments under controlled conditions. Even if most of the collected nymphs were positive to at least one virus, transmission occurred only to a low number of test grapevines. The transmission frequency of GLRaV-3 was the highest, whereas GVA was transmitted to few test plants. The transmission of multiple viruses occurred at low rates, and nymphs that acquired all the three viruses then failed to transmit them together. Statistical analyses showed that the three viruses were independently acquired and transmitted by H. bohemicus and neither synergistic nor antagonistic interactions occurred among them. GVA and GLRaVs transmission efficiencies by H. bohemicus were lower than those reported for other mealybug vectors. This finding is consistent with the slow spread of leafroll and rugose wood diseases observed in Northern Italy, where H. bohemicus is the predominant vector species. [ABSTRACT FROM AUTHOR]

We review direct and indirect effects of climate change on both the grapevine plant as a host for phytophagous insects, as well as on grape insect pests, their natural enemies and corresponding future grape plant protection strategies. Phenology, voltinism and distribution ranges are well known traits of many arthropods influenced by temperature as the key abiotic factor and thus by current and future climate change scenarios. Case studies of grapevine pests based on data from three decades point to clear changes in phenology of grape berry moths, shifts in distribution ranges of leafhoppers as vectors of grapevine diseases and range expansion of grapevine mealybugs. These case studies also illustrate the need to include data on putatively changed tri-trophic interactions in vineyards when predicting impacts of climate change on grapevine pest insects. Hence, future pest management strategies should be based on a sound set of field data obtained for both pests and antagonists under changed abiotic conditions, which can also build the basis for refining and extending currently existing models for forecasting population levels of respective insect pests. [ABSTRACT FROM AUTHOR]

Most Northeastern US viticulture cannot rely on the European grape species (Vitis vinifera) due to its lack of cold and disease resistance. The Northeastern US is a center for grape biodiversity. In parallel with this host diversity, a myriad of foliar diseases infect grapes in the Northeast. Crosses of native American grape species (e.g. Vitis riparia) with V. vinifera are cultivars with a range of cold and disease resistance that have potential for Northeastern viticulture. While we expect the American hybrids to have acquired some disease resistance from the American lineages, reports of disease resistance are inconsistent. More specifically, whether there is a relationship between resistances to necrotrophs and biotrophs is unknown. Quantifying resistances and understanding resistance interactions are essential to breeding effort and integrated pest management. We quantified how disease resistances vary across cultivars and the relationship between resistances to different pathogen types (necrotrophs and biotrophs). In 2021, we created a collection of grape leaf necrotrophs from cultivated and wild grapes from Massachusetts. Based on sequencing, most necrotrophs belonged to the genera Botryosphaeria, Colletotrichum, Diaporthe, and Didymella. In the laboratory, we quantified host susceptibility to necrotrophs using leaf disc assays. Pathogenicity of a subset of three necrotrophs in the genera Colletotrichum and Didymella was measured on four hybrid grape cultivars. Regardless of cultivars, Colletotrichum caused larger necroses than Didymella. Resistance to necrotrophs also varied according to cultivar, 'Vidal' was the most resistant followed by 'Frontenac', 'Riesling' and 'Noiret'. In the field, we quantified host susceptibility to the biotroph downy mildew using the percentage of the leaf surface infected by the disease. We quantified the disease susceptibility of nine cultivars to downy mildew in our cultivar trial in Belchertown, Massachussetts in September 2021. Resistance to downy midlew varied according to cultivar, from most resistant to least resistant being as follows: 'Marquette', 'Frontenac', 'Noiret', 'Chambourcin', 'St. Croix', 'La Crescent', 'Corot Noir', 'Riesling', and 'Vidal'. Based on the four cultivars tested both in the laboratory and in the field, we did not see a correlation between resistance to necrotrophs and resistance to biotrophs. [ABSTRACT FROM AUTHOR]

Grapevine breeding for biotic stress resistance is a valuable strategy to embrace the principles of the European Green Deal, which will be one of the strongest drivers of the Agrifood research sector in the next decades. Grapevines are challenged by a range of diseases and pests, causing economic losses, and requiring often costly approaches to mitigate damage. Public interest in reducing the use of chemicals is a related challenge, along with climate change. All these aspects converge upon the urgent need for sustainable viticulture. The Vitis gene pool provides vast resources for the development of genetic resistance in rootstock and scion cultivars, but the search is not yet exhausted. According to BrAPI, germplasm consists of wild/acquired accessions as well as breeding products (breeding selections and cultivars). The enhancement of the entire germplasm is a crucial step. This is expressed in fingerprinting and high-throughput genotyping as well as phenotyping for disease and pest resistance, even in retroactive mode on traditional breeding products and acquired accessions. In fact, classical breeding approaches have made great strides in the development of cultivars with adaptive traits. Recent access to 'omic technologies, coupled with advanced phenotyping tools, has further facilitated the identification of useful loci, along with rapid trait introgression from wild species. Moreover, marker technologies (mainly accessible microsatellitebased systems) are now used in Marker-Assisted Selection to stack multiple loci/genes for the same trait into a single superior genotype. It would be relevant to phenotypically test these "stacked" genotypes in controlled lab settings as well as in different challenging environments worldwide. This effort would represent a step forward in terms of understanding genotype (loci) - pathogen (races) interaction. Genomic technologies will finally impact germplasm characterization, enabling the identification of candidate resistance genes and thereby facilitating "Breeding by Design" approaches. [ABSTRACT FROM AUTHOR]

Grapevine downy mildew (DM), caused by the oomycete Plasmopara viticola (Berk. & Curt.) Berlese & de Toni, is a major disease, especially in humid viticultural areas. Development of resistant cultivars is an important objective for grapevine breeding. To establish a reliable and inexpensive quantitative method to aid in breeding for DM resistance, we improved the method for counting the number of sporangia on leaf discs, and developed a method for counting the number of sporangia in solution. To prevent the loss of DM sporangia from adhesion onto plastic ware, we found as little as 0.01% Tween 20 was effective. On the other hand, this detergent was shown to have a severe inhibitory effect upon DM infection of leaves. We developed a sporangia counting method using dried droplets of DM suspensions, and the method was highly correlated with counting by hemacytometer (R²> 0.96). The nonparametric Spearman's rank correlations between visual rating and the number of the sporangia were as high as p = 0.82 to 0.91, suggesting that evaluation by the visual rating could provide a good estimate of the sporangia numbers on leaf discs. We established a high-throughput and inexpensive method with acceptable accuracy for DM resistance evaluation based on a leaf disc assay, and our results suggested that visual ratings of infected leaf discs provide a good estimate of sporangia numbers. [ABSTRACT FROM AUTHOR]

"Bois noir" (BN) is a grapevine yellows disease, associated with phytoplasma strains related to 'Candidatus Phytoplasma solani', that causes severe losses to viticulture in the Euro-Mediterranean basin. Due to the complex ecological cycle of its etiological agent, BN epidemiology is only partially known, and no effective control strategies have been developed. Numerous studies have focused on molecular characterization of BN phytoplasma strains, to identify molecular markers useful to accurately describe their genetic diversity, geographic distribution and host range. In the present study, a multiple gene analysess were carried out on 16S rRNA, tuf, vmp1, and stamp genes to study the genetic variability among 18 BN phytoplasma strains detected in diverse regions of the Republic of Macedonia. Restriction fragment length polymorphism (RFLP) assays showed the presence of one 16S rRNA (16SrXII-A), two tuf (tuf-type a, tuf-type b), five vmp1 (V2-TA, V3, V4, V14, V18), and three stamp (S1, S2, S3) gene patterns among the examined strains. Based on the collective RFLP patterns, seven genotypes (Mac1 to Mac7) were described as evidence for genetic heterogeneity, and highlighting their prevalence and distribution in the investigated regions. Phylogenetic analyses on vmp1 and stamp genes underlined the affiliation of Macedonian BN phytoplasma strains to clusters associated with distinct ecologies. [ABSTRACT FROM AUTHOR]

Development and optimisation of alternative strategies to reduce the use of classic chemical inputs for protection against diseases in vineyard is becoming a necessity. Among these strategies, one of the most promising consists in the stimulation and/or potentiation of the grapevine defence responses by the means of elicitors. Elicitors are highly diverse molecules both in nature and origins. This review aims at providing an overview of the current knowledge on these molecules and will highlight their potential efficacy from the laboratory in controlled conditions to vineyards. Recent findings and concepts (especially on plant innate immunity) and the new terminology (microbe-associated molecular patterns, effectors, etc.) are also discussed in this context. Other objectives of this review are to highlight the difficulty of transferring elicitors use and results from the controlled conditions to the vineyard, to determine their practical and effective use in viticulture and to propose ideas for improving their efficacy in non-controlled conditions. [ABSTRACT FROM AUTHOR]

Among fungal grapevine trunk diseases, esca proper poses a significant threat for viticulture. Apoplexy, mainly occurring on grapevines affected by esca proper, is also a threat. To verify if different responses are activated in the woody tissues of apoplectic (A) and esca proper-affected (E) vines, two-dimensional gel electrophoresis coupled to mass spectrometry analysis was used to examine changes in the trunk wood of E and A field-grown plants. Asymptomatic and black streaked trunk (BST) wood from A and E plants were compared to asymptomatic and BST wood of control plants. Twenty-seven differentially expressed protein spots were identified. For eleven targeted proteins, expression of the relative transcripts was also monitored by qRT-PCR. Hierarchical tree clustering revealed differences in the distribution of spots containing carbohydrate metabolism proteins and heat shock proteins between asymptomatic- and BST-wood of grapevine, irrespective of the type of plant examined (control or diseased grapevines). Asymptomatic wood was mainly characterized by down-expression of proteins involved in cell growth and defense responses. The proteome of BST wood, characterized by extensive presence of grapevine trunk disease agents, revealed over-expression of proteins involved in defense. There was no evidence of strong different response in the trunk wood of apoplectic and esca proper affected plants. This could mean that, despite the different feature of these external crown symptoms, grapevine responses at trunk wood level is very similar in both cases. This plant response might therefore either simply be due to the fact that plants can react in the same way to different stresses, or that apoplexy represents a different effect provoked by the same cause or causal agent(s). [ABSTRACT FROM AUTHOR]

Rain-shelter cultivation is an effective cultural method to prevent rainfall damage during grape harvest and widely applied in the Chinese rainy regions. In this study we investigated the effect of rain-shelter cultivation on grape diseases and phenolic composition in the skins of Vitis vinifera cv. Cabernet Gernischet grape berries through the comparison with open-field cultivation at two vintages (2010 and 2011). The results showed that rain-shelter cultivation reduced the incidence of grape diseases significantly and delayed the maturation of Cabernet Gernischet fruits. With regards to most of the phenolic compounds identified in this study, their content in grape samples under rain-shelter cultivation was decreased compared to those under open-field cultivation. However, rain-shelter cultivation stimulated the accumulation of dihydroquercetin-3-O-rhamnoside in grape skins during grape maturation. These were related with micrometeorological alterations in vineyards by using plastic covering under rain-shelter cultivation. It suggests the rain-shelter cultivation makes possible the cultivation of "Cabernet Gernischet" grapes in an organic production system, for providing a decrease in the incidence of diseases and the dependence on chemical pesticides in the grape and wine industry. [ABSTRACT FROM AUTHOR]

The appearance of the Flavescence Dorée phytoplasma and the possibility of its rapid spread by its vector, the American Grapevine Leafhopper (Scaphoideus titanusBall) (AGVL), represent a serious threat to viticulture production in Slovenia and elsewhere in Europe. Insecticide treatment represents one of major means of reducing the abundance of AGVL in wine-growing areas. In the period from 2010 to 2011, five insecticides against AGVL were tested, and the efficacy of the substances was calculated according to the number of nymphs (at 2, 7, 14 and 21 d after application), which were counted on the grapevine leaves. In both years, the highest cumulative efficacy (96–97% or 0.01 nymphs/leaf) was confirmed for thiamethoxam, whereas chlorpyrifos-methyl showed a very high cumulative efficacy (87–89% or 0.01–0.02 nymphs/leaf). In 2010, indoxacarb exhibited only a 43% (0.09 nymphs/leaf) cumulative efficacy; however, its substitute in 2011, chlorpyrifos, was more effective (73% or 0.05 nymphs/leaf). A single application of pyrethrin demonstrated only 45–61% (0.05–0.09 nymphs/leaf) efficacy. Based on the results of our research, we recommend the use of thiamethoxam and chlorpyrifos-methyl against AGVL. [ABSTRACT FROM PUBLISHER]

Background and aims: The fungus Botrytis cinerea is a common problem in viticulture and leads to serious losses in both yield and quality. The objective was to study the potential of the antagonist Pantoea ananatis BLBT1-08 for controlling this disease. Methods: Pathogen suppression by Pantoea treatments was investigated in different field trials and in detached leaf assays. The mode of action was studied by confocal laser scanning microscopy of treated grape leaves and by in vitro assays. Results: The introduction of P. ananatis BLBT1-08 in a 3-year field trial resulted in statistically significant reduction of disease symptoms. However, B. cinerea abundance, measured by quantitative real-time polymerase chain reaction of a B. cinerea specific gene, was not reduced when compared to non-treated, symptom-free leaves. A DsRed fluorescent protein labeled BLBT1-08 strain showed a high phyllosphere competence and competition on the leaf surface, but did not colonize the inner parts of plant tissue. Germination of B. cinerea was not inhibited by BLBT1-08 on the leaf, but mycelial growth and symptoms were suppressed without direct pathogen-antagonist contact. The antimicrobial activity was amino acid and temperature dependent. Conclusion: P. ananatis BLBT1-08 is a competitive and promising biocontrol agent for the control of B. cinerea and is highly effective at reducing disease incidence. [ABSTRACT FROM AUTHOR]

Abstract: To date, several viroid species have been shown to infect grapevine, including Hop stunt viroid (HpSVd), Citrus exocortis viroid (CEVd), Australian grapevine viroid (AGVd), Grapevine yellow speckle viroid-1 (GYSVd-1), Grapevine yellow speckle viroid-2 (GYSVd-2) and a tentative new species, Grapevine yellow speckle viroid-3 (GYSVd-3). Here, we identified and analyzed the distribution, genetic diversity, and molecular properties of viroids infecting grapevine cultivated in China and Japan, including old grapevines. The analysis showed that all the five known viroids and a tentative species GYSVd-3 infecting grapevine exist in China, and three of them (HpSVd, GYSVd-1 and GYSVd-3) exist in Japan. The contrast in diversity of viroid species in old grapevines from China and Japan may reflect different history of viticulture between the two countries. In general, the species of viroids infecting grapevine in China, as well as those in Iran and Australia, were more diverse than in the other countries. The population structure of viroids infecting grapevine in China and Japan showed species-dependency; i.e., HpSVd shared similar population structures in both countries, but GYSVd-1, GYSVd-2, and AGVd showed regional disparity even within the same country, although the role of sequence diversity in the biology of viroids infecting grapevine, such as the pathogenicity and evolution, still needs further study. [Copyright &y& Elsevier]

The management options for grape phylloxera, Daktulosphaira vitifoliae, a monophagous insect pest of Vitis species are reviewed. Although in a worldwide context, grape phylloxera is managed predominantly by the use of resistant rootstocks developed through conventional breeding of hybrid crosses of American Vitis species, this management aspect is largely excluded from the review so that emerging technologies in the field of detection, quarantine and alternative management are discussed. In some viticulture regions of the world, where grape phylloxera's geographic distribution is limited (e.g. Australia), the pest is managed through a combination of surveillance, detection and quarantine. Although some alternative management options for grape phylloxera exist they have received relatively limited research attention because of the relative success of resistant rootstocks. The resilience of resistant rootstocks as the primary management option could also be challenged in the future by host-plant interactions with diverse grape phylloxera clonal lineages and by potential impacts of climate change on both grapevine and grape phylloxera distribution. A range of control options exist which could be integrated into an improved management system for grape phylloxera. Priority areas for future evaluation and further development include early detection techniques, investigation into the use of biological control agents and development of an integrated approach to grapevine phylloxera management. [ABSTRACT FROM AUTHOR]

Background and Aims: Australian certification programs that provide high-health planting material depend on accurate virus detection methods. The reliability of enzyme-linked immunosorbent assays (ELISAs) and reverse transcription-polymerase chain reaction (RT-PCR) tests for virus detection was compared in Australian conditions. Methods and Results: Replicate trials were established in a hot climate and a cool climate with grapevines that were uninoculated or inoculated with Grapevine virus A, Grapevine fleck virus, Grapevine leafroll-associated virus (GLRaV)-2 and GLRaV-3. Grapevines were tested monthly for virus during 3 years. RT-PCR detected viruses more frequently than ELISA, and the reliability of both tests increased after 12 months and up to 3 years post-inoculation in both climates. Conclusions: Viruses may not be consistently detected until 12 months after an infection event. RT-PCR is more reliable than ELISA for virus detection during spring and summer. However, detection of viruses was rarely 100% efficient, and retesting of grapevines is recommended to improve the rate of detection. Significance of the Study: Validated diagnostic procedures were developed to improve the reliability of grapevine virus detection in Australia. [ABSTRACT FROM AUTHOR]