Search

In the context of global efforts to improve food quality against the backdrop of climate change and increasing demands for food, this study sought to investigate the influence of tillage and fertilization methods on essential nutritional components. Thus, this extensive investigation into the variability of organic acid, sugar, and vitamin content within berries over the years 2020 to 2022 shows the critical influence of agricultural practices on the nutritional quality of grape. Our findings revealed significant fluctuations in the levels of various organic acids, with oxalic and propionic acids seeing a notable increase in 2022, while tartaric, citric, and maleic acids decreased. Similarly, a significant rise in sucrose, glucose, and fructose levels was documented by 2022, alongside a variable trend in vitamin content. The PCA results revealed a clear impact of tillage and organic amendments on the biochemical composition of Royal grapes. Heatmap findings confirmed the results obtained from PCA and showed that certain treatments resulted in high organic acid content, while others resulted in high sugar content. However, disc harrow and olive blackwater 2021 followed by disc harrow and Antep radish 2021 and no‐tillage broccoli 2020 were the best treatments with a balanced distribution of organic acids, soluble sugars, and vitamins among all treatments. On the other hand, chisel and olive blackwater '20 was the treatment with the lowest ratio of organic acids, sugars, and vitamins, followed by chisel and Antep radish 2020. These results show that the concentration of organic acids, soluble sugars, and vitamins in grapes is more affected by the tillage method than the type of organic fertilizer used. To sum up, our study holds valuable implications for viticulture and agriculture at large, highlighting the potential to tailor farming practices for enhanced nutritional outcomes. Such advancements not only promise to elevate the quality of agricultural produce but also contribute to the broader objective of achieving food security and nutritional adequacy, thus offering a roadmap for future research and practice in sustainable agriculture and viticulture. [ABSTRACT FROM AUTHOR]

The dynamic fluctuations in autumn temperatures, particularly the marked diurnal variations and the subsequent precipitous drops are key and a pivotal role in viticulture, as they critically influence the acclimation process of grapevines to cold, thereby directly impacting their survival and productivity in cold-climate regions. In this comprehensive study, we investigated the cold hardiness of four grapevine cultivars: 'Itasca', 'Frontenac', 'La Crescent', and 'Marquette', focusing on how these cultivars and their individual buds (1st, 2nd, 3rd, 4th, 5th, 6th, 7th, 8th, and 9th) respond to fluctuating weather and low temperatures typical of autumn [-1.1℃ (30°F) -9.4℃ (15°F) and -17.8℃ (0°F)]. Our results illuminated the striking variability in cold hardiness that was manifest not only among the different cultivars but also within individual buds on the same vine, underscoring the critical influence of bud position on a vine for cold hardiness. 'Frontenac' showed greater cold hardiness at critical temperatures at which 10%, and 50% of the dormant buds were lethally affected by cold (LT10 and LT50) compared to 'Itasca' and 'La Crescent', with 'Marquette' exhibiting intermediate values. However, in cultivars such as 'Itasca' and 'Marquette', certain buds demonstrated a pronounced hardiness when faced with colder temperatures, while others exhibited a heightened sensitivity, thereby revealing a nuanced interplay between bud position and a vine's ability to withstand cold stress. Our study revealed a notable divergence from traditional viticulture understanding; apical buds demonstrated greater cold hardiness than basal buds and opened new paths for research into grapevine physiology. Our results also indicated a significant trend wherein older vines across all studied cultivars displayed enhanced cold hardiness, particularly pronounced at the critical LT50 and the critical temperature at which 90% of the dormant buds were lethally affected by cold (LT90) thresholds, in comparison to younger vines. Moreover, our findings shed light on the impact of autumn's diurnal temperature variations and the subsequent drop in temperatures on vine cold hardiness, thus highlighted the complex interplay between environmental temperature dynamics and dormant bud hardiness. In conclusion, our study showed that the cold damage observed in grapevines in North Dakota was not a result of extreme temperature fluctuations in the fall. This was confirmed by testing the vines after they had reached various threshold temperatures through differential thermal analysis (DTA) and optical differential nucleation and expansion analysis (ODNEAL) methodologies, particularly before the onset of severe pre-winter cold conditions. These comprehensive findings highlighted the complexity of the vine's response to climatic conditions and viticultural management, pointing to the need for specific strategies in vineyard management and cultivar selection to optimize bud hardiness and productivity in the face of various environmental challenges, especially in cold climate viticulture. [ABSTRACT FROM AUTHOR]

The dynamic fluctuations in autumn temperatures, particularly the marked diurnal variations and the subsequent precipitous drops are key and a pivotal role in viticulture, as they critically influence the acclimation process of grapevines to cold, thereby directly impacting their survival and productivity in cold-climate regions. In this comprehensive study, we investigated the cold hardiness of four grapevine cultivars: ‘Itasca’, ‘Frontenac’, ‘La Crescent’, and ‘Marquette’, focusing on how these cultivars and their individual buds (1st, 2nd, 3rd, 4th, 5th, 6th, 7th, 8th, and 9th) respond to fluctuating weather and low temperatures typical of autumn [-1.1°C (30°F) -9.4°C (15°F) and -17.8°C (0°F)]. Our results illuminated the striking variability in cold hardiness that was manifest not only among the different cultivars but also within individual buds on the same vine, underscoring the critical influence of bud position on a vine for cold hardiness. ‘Frontenac’ showed greater cold hardiness at critical temperatures at which 10%, and 50% of the dormant buds were lethally affected by cold (LT10 and LT50) compared to ‘Itasca’ and ‘La Crescent’, with ‘Marquette’ exhibiting intermediate values. However, in cultivars such as ‘Itasca’ and ‘Marquette’, certain buds demonstrated a pronounced hardiness when faced with colder temperatures, while others exhibited a heightened sensitivity, thereby revealing a nuanced interplay between bud position and a vine’s ability to withstand cold stress. Our study revealed a notable divergence from traditional viticulture understanding; apical buds demonstrated greater cold hardiness than basal buds and opened new paths for research into grapevine physiology. Our results also indicated a significant trend wherein older vines across all studied cultivars displayed enhanced cold hardiness, particularly pronounced at the critical LT50 and the critical temperature at which 90% of the dormant buds were lethally affected by cold (LT90) thresholds, in comparison to younger vines. Moreover, our findings shed light on the impact of autumn’s diurnal temperature variations and the subsequent drop in temperatures on vine cold hardiness, thus highlighted the complex interplay between environmental temperature dynamics and dormant bud hardiness. In conclusion, our study showed that the cold damage observed in grapevines in North Dakota was not a result of extreme temperature fluctuations in the fall. This was confirmed by testing the vines after they had reached various threshold temperatures through differential thermal analysis (DTA) and optical differential nucleation and expansion analysis (ODNEAL) methodologies, particularly before the onset of severe pre-winter cold conditions. These comprehensive findings highlighted the complexity of the vine’s response to climatic conditions and viticultural management, pointing to the need for specific strategies in vineyard management and cultivar selection to optimize bud hardiness and productivity in the face of various environmental challenges, especially in cold climate viticulture.

Grafting is widely used in horticulture. Shortly after grafting, callus tissues appear at the graft interface and the vascular tissues of the scion and rootstock connect. The graft interface contains a complex mix of tissues, we hypothesised that each tissue has its own metabolic response to wounding/grafting and accumulates different metabolites at different rates. We made intact and wounded cuttings and grafts of grapevine, and then measured changes in bulk flavonoid, phenolic acid and stilbenoid concentration and used metabolite imaging to study tissue‐specific responses. We show that some metabolites rapidly accumulate in specific tissues after grafting, for example, stilbene monomers accumulate in necrotic tissues surrounding mature xylem vessels. Whereas other metabolites, such as complex stilbenes, accumulate in the same tissues at later stages. We also observe that other metabolites accumulate in the newly formed callus tissue and identify genotype‐specific responses. In addition, exogenous resveratrol application did not modify grafting success rate, potentially suggesting that the accumulation of resveratrol at the graft interface is not linked to graft union formation. The increasing concentration of complex stilbenes often occurs in response to plant stresses (via unknown mechanisms), and potentially increases antioxidant activity and antifungal capacities. Summary statement: We show that after grafting stilbenes accumulate specifically in necrotic tissues, whereas other compounds accumulate in the newly formed callus tissues. This suggests that these compounds have different roles in wounding healing and graft union formation. [ABSTRACT FROM AUTHOR]

'Flavescence dorée' (FD) is a quarantine grapevine disease associated with FD phytoplasmas (FDp). In Switzerland, FD was first reported in 2004 in the southern part of the Canton Ticino, from where, within a few years, it spread to nearly the entire vineyard area of the Southern Alps, despite the mandatory control measures. The aim of this study was to assess the possible role of gone‐wild grapevines (GWGVs) in forests resulting from early abandoned vineyards as a habitat for the main FDp vector, Scaphoideus titanus, and for the best alternative vector candidate, Orientus ishidae, as well as an FDp inoculum reservoir in Southern Switzerland. Leaf samples were collected in 20 plots and tested for the presence of FDp. Moreover, fifteen of these plots were monitored with yellow sticky traps to determine the presence and infection status of insect vectors. Finally, a hatching experiment under controlled conditions was conducted to investigate the possible oviposition activity by FDp vectors, using wood collected from GWGVs present in 11 forest sites in the surroundings of cultivated vineyards. GWGVs in forests were confirmed to act as an FDp reservoir and to represent a suitable habitat for FDp vectors (in particular, for S. titanus). Abandoned vineyards should be included in the FD management strategy and their systematic rogueing should be applied as soon as possible and in particular before the transition from vineyard to forest occurs, in order to avoid the survival of S. titanus and the establishment of inoculum in uncontrolled landscape compartments. [ABSTRACT FROM AUTHOR]

BACKGROUND: Grafting is widely used in horticulture and rootstocks are known to modify scion growth and adaptation to soil conditions. However, the role of scion genotype in regulating rootstock development and functioning has remained largely unexplored. In this study, reciprocal grafts of two grapevine genotypes were produced as well as the corresponding homo-graft controls. These plants were subjected to a low phosphate (LP) treatment and transcriptome profiling by RNA sequencing was done on root samples collected 27 h after the onset of the LP treatment. RESULTS: A set of transcripts responsive to the LP treatment in all scion/rootstock combinations was identified. Gene expression patterns associated with genetic variation in response to LP were identified by comparing the response of the two homo-grafts. In addition, the scion was shown to modify root transcriptome responses to LP in a rootstock dependent manner. A weighted gene co-expression network analysis identified modules of correlated genes; the analysis of the association of these modules with the phosphate treatment, and the scion and rootstock genotype identified potential hub genes. CONCLUSIONS: This study provides insights into the response of grafted grapevine to phosphate supply and identifies potential shoot-to-root signals that could vary between different grapevine genotypes.

ABSTRACT The knowledge of correlations between multiple characteristics in plant breeding leads to more effective selection strategies. The path analysis allows refining these correlations and partitioning them into direct and indirect effects on the main variable. The path analysis becomes more effective when based on predicted genotypic values rather than phenotypic values. The objective was to evaluate correlations between the main agronomic characteristics of grapevine cultivation and their direct and indirect effects on yield per plant to improve selection strategies to reach superior progenies. A randomized complete block design was installed using four cultivars and two rootstocks, five repetitions, and plots of four plants. Data from three crop seasons were analyzed from a mixed model and genetic correlations were subject to the path analysis. A high and positive significant correlation was found between average fruit production and the number of clusters per plant. On the other hand, the average production per plant showed a low correlation to cluster width and height per grapevine. Wider and higher berries tend to increase berry fresh mass and therefore increase the contents of soluble solids and reducing sugars. Among the features, the number of clusters per plant has the strongest direct effect on fruit production in grape cultivars. Berry fresh mass, berry length, and berry width were indirectly influenced by the number of clusters and showed high heritability compared to yield and number of clusters. These characteristics could be used in indirect selection.

The objective of this study was to estimate the repeatability coefficients, optimal number of harvests, and genetic gains and to select superior hybrids of table grapes for the development of cultivars adapted to semiarid conditions in Brazil. The mixed model methodology REML/BLUP was used to estimate the variance components and predict the genotypic values. Two hundred table grape hybrids were evaluated during six harvests at the Mandacaru Experimental Field in Embrapa Semiárido, Juazeiro, Bahia, Brazil. The experiment was implemented in the absence of an experimental design, with a single individual of each genotype. Twelve quantitative morphoagronomic variables were evaluated. The repeatability coefficients were as follows: 0.20 (yield), 0.18 (number of bunches), 0.37 (bunch length), 0.30 (bunch width), 0.47 (bunch weight), 0.60 (berry length), 0.68 (bunch diameter), 0.70 (berry weight), 0.14 (soluble solids content) and 0.13 (ratio). The accuracies obtained by performing m repeated measurements revealed that for berry characteristics, only one measurement was sufficient; two measurements were required for the length and weight of the bunch; three measurements were required for the bunch width; four measurements were required for the yield and five measurements for the number of bunches; for the soluble solids content and ratio, seven and six measurements were needed, respectively. Individual genotypic selection allows high genetic gains for bunch and berry traits and satisfactory gains for quality traits. In addition, three superior genotypes ('BRS Tainá', CPATSA 05.168 and CPATSA 79.100) were identified for eight traits simultaneously, with 'BRS Tainá' being identified as an apyrenic cultivar. [ABSTRACT FROM AUTHOR]

ABSTRACT Several grafting methods have been developed, and bench grafting with stratification is the most widely used technique, except in Brazil, which is still in adaptation. The objective of this study was to evaluate for how long plant material can be stored before the grafting and the optimum temperature for stratification. Cultivar 'Paulsen 1103' was used as rootstock and 'Niagara Rosada' as scion cultivar. The storage period treatments were 0, 30, 60 and 90 days at the temperature of 3 ℃ and 95% of relative humidity. After the storage period, the branches were removed from the cold chamber, taken to grafting, and then placed at 19 °C and 24 °C for stratification. After 21 days of stratification, the vine grafts were planted in commercial substrate and left to grow for 160 days. The vine cuttings of cultivars Niagara and Paulsen 1103 can be stored in cold chamber at 3 °C for 90 days and, during this period, bench grafting can be performed at any time. However, the vines from cuttings stored in cold chamber for more than 30 days have better growth. It is recommended to stratify the vine grafts at 19 °C.

Intensive breeding programmes have been carried out to obtain high‐quality seedless grape cultivars. Seedless grape cultivars were used as pollinizer parents, but the number of hybrid seeds and the viability of the seed obtained could differ greatly. In this study, carried out over 3 years, the results obtained from crossing with some pollinizer cultivars belonging to different Vitis species were compared. Maternal cultivars that do not need emasculation (male sterile) and emasculated cultivars were also compared. Evaluations were based on the total number of hybrid seeds and the proportion of viable seeds. In addition, the effects of various treatments on the rates of germination of the hybrid seed were compared. Although the female parents (with female flower structure) produced more seed than did hermaphrodite mothers in 2019, different results were obtained in cross‐breeding studies in 2018 and 2020. Cold stratification was very effective in increasing germination by breaking dormancy of the hybrid seed. In addition, after treatment of cold moist storage (cold stratification), keeping the seed in distilled water overnight before planting increased germination. Although large numbers of seeds were produced by the genotype 86/1 and the cultivar 'Beyaz Çavuş', both of which do not require emasculation, many of these seeds did not germinate. Crosses with the cultivar 'Red Globe' as the maternal parent produced large numbers of viable seeds and high germination rates. [ABSTRACT FROM AUTHOR]

Asian grapevine leaf rust (AGLR) causes severe crop losses in Brazilian viticulture, mainly in latitudes <25°S. The purpose of this study was to identify the pathogen(s) involved with AGLR in Brazil, based on phylogenetic and morphological analysis and pathogenicity tests. In total, 56 monouredinial isolates from six Brazilian states were identified using the internal transcribed spacer 2 and the large subunit rRNA gene D1/D2 regions. All 50 isolates from the south‐central region were classified as Neophysopella tropicalis, and the other six isolates from the north‐east region as Neophysopella meliosmae‐myrianthae. This result provides evidence that two pathogen introductions from different sources may have occurred in the country. For both species, paraphyses were cylindrical, incurved, aseptate, and hyaline, while urediniospores were short‐pedicellate, obovoid or obovoid‐ellipsoid, with the wall colourless or pale yellowish, evenly echinulate. Representative isolates from both species caused typical AGLR symptoms on Vitis vinifera 'Merlot' and V. labrusca 'Niagara Rosada'. Overall, regardless of the Neophysopella species, isolates caused similar leaf disease severities. Higher disease severity was observed in Niagara Rosada (average of 40.3% of diseased leaf area) compared to Merlot (20.5%). This study reports, for the first time, the characterization of Neophysopella species associated with AGLR in Brazil. [ABSTRACT FROM AUTHOR]

Black foot disease of grapevines is a major economic issue for the viticulture industry worldwide. The disease is mainly associated with a complex of pathogen species within the genera Dactylonectria and Ilyonectria. The susceptibility of six grapevine rootstock cultivars to black foot disease under field conditions was assessed. Callused rootstocks of 101-14, 5C, 420A, Riparia Gloire, Schwarzmann and 3309C were planted into soil containing low natural pathogen populations or inoculated with isolates representing the species diversity in New Zealand. Disease incidence, disease severity and dry weight accumulation were assessed after 8 months of growth. Root and shoot dry weights were not significantly affected by inoculation treatment, but differed among rootstock cultivars, with cultivar 420A having the lowest root and shoot dry weight, cultivar 3309C having the largest shoot dry weight and cultivar 5C the largest root dry weight. The relative susceptibility of rootstocks differed significantly depending on whether they were grown under low natural inoculum pressure or a higher pressure in artificially inoculated soil. Schwarzmann and Riparia Gloire rootstock cultivars were the least susceptible under natural low inoculum pressure, but were the most susceptible in inoculated soil. In contrast, 5C was one of the most susceptible under low inoculum levels but was the least susceptible under high pathogen pressure. The result of the study indicate that black foot pathogen inoculum levels in soil affect the relative susceptibility of grapevine rootstocks to infection, and may have implications for the selection of rootstocks for planting. [ABSTRACT FROM AUTHOR]

Several grafting methods have been developed, and bench grafting with stratification is the most widely used technique, except in Brazil, which is still in adaptation. The objective of this study was to evaluate for how long plant material can be stored before the grafting and the optimum temperature for stratification. Cultivar 'Paulsen 1103' was used as rootstock and 'Niagara Rosada' as scion cultivar. The storage period treatments were 0, 30, 60 and 90 days at the temperature of 3 °C and 95% of relative humidity. After the storage period, the branches were removed from the cold chamber, taken to grafting, and then placed at 19 °C and 24 °C for stratification. After 21 days of stratification, the vine grafts were planted in commercial substrate and left to grow for 160 days. The vine cuttings of cultivars Niagara and Paulsen 1103 can be stored in cold chamber at 3 °C for 90 days and, during this period, bench grafting can be performed at any time. However, the vines from cuttings stored in cold chamber for more than 30 days have better growth. It is recommended to stratify the vine grafts at 19 °C. [ABSTRACT FROM AUTHOR]

In the State of Goiás, studies related to the vine's responses to the region's edaphoclimatic conditions are scarce. Therefore, the objective of this work was to evaluate the growth of three vine rootstock cultivars, IAC 572 'Jales', IAC 313 'Tropical' and IAC 766 'Campinas', in the region of Goiânia, GO, after drastic pruning for uniformity. To evaluate the growth of rootstocks, the experiment was carried out in random blocks, in a double factorial scheme (3x7), with five replications, each repetition formed by a plant. The first factor consisted of three rootstocks: IAC 313 'Tropical', IAC 572 'Jales' and IAC 766 'Campinas'. The plants were evaluated after 45 days after a drastic uniformization pruning, totaling seven evaluations (45, 60, 75, 90, 105, 120, 135 days after pruning), this being the second factor. The diameter of the main branch at the height of grafting (80 cm) and length of the main branch were evaluated. With the data on the diameter and length of the main branch, the absolute growth rate in diameter and length was calculated. The IAC 572 'Jales' rootstock cultivar has greater vigor for branch growth, being 69% and 47.3% longer in length, and 49.8% and 18.8% longer in diameter than the IAC rootstock. IAC 313 'Tropical' 'and' IAC 766 'Campinas', respectively. The IAC 766 'Campinas' rootstock cultivar, although it has low vigor in branch growth, presents satisfactory development. [ABSTRACT FROM AUTHOR]

Previous studies about superoxide dismutase (SOD) genes were mostly with regard to biotic and abiotic stress responses. Some reports have indicated SOD genes may play an important role in plant development. However, little is known about the relationship of SOD genes with grape berry ripening. Thirteen VviSOD genes were identified from grape genome sequences based on the bioinformatic method. Phylogenetic analysis indicated that these VviSODs could be divided into two groups. The genes of VviCu/ZnSOD1a and VviCu/ZnSOD1c were identified as tandem replication genes. The expression analyses based on RNA-Seq and qRT-PCR results in 'Kyoho' and its early-ripening bud mutant, 'Fengzao', demonstrated that the VviSOD genes involved in the grape berry ripening and VviCu/ZnSOD1c were the main candidate. Sequence analysis of VviCu/ZnSOD1c gene in 'Fengzao' showed that the coding sequence was the same as that of 'Kyoho'. According to the bioinformatic and expression analysis, VviSOD genes probably involved in the grape berry ripening and VviCu/ZnSOD1c was selected as the main candidate to further explore its potential role in the early ripening of 'Fengzao'. [ABSTRACT FROM AUTHOR]

Inflorescence architecture provides the scaffold on which flowers and fruits develop, and consequently is a primary trait under investigation in many crop systems. Yet the challenge remains to analyse these complex 3D branching structures with appropriate tools. High information content datasets are required to represent the actual structure and facilitate full analysis of both the geometric and the topological features relevant to phenotypic variation in order to clarify evolutionary and developmental inflorescence patterns. We combined advanced imaging (X-ray tomography) and computational approaches (topological and geometric data analysis and structural simulations) to comprehensively characterize grapevine inflorescence architecture (the rachis and all branches without berries) among 10 wild Vitis species. Clustering and correlation analyses revealed unexpected relationships, for example pedicel branch angles were largely independent of other traits. We identified multivariate traits that typified species, which allowed us to classify species with 78.3% accuracy, versus 10% by chance. Twelve traits had strong signals across phylogenetic clades, providing insight into the evolution of inflorescence architecture. We provide an advanced framework to quantify 3D inflorescence and other branched plant structures that can be used to tease apart subtle, heritable features for a better understanding of genetic and environmental effects on plant phenotypes. [ABSTRACT FROM AUTHOR]

Overcoming host defensive traits is a prerequisite to establish compatible plant-parasite interactions. Following parasite perception, jasmonic (JA) and salicylic acid (SA) signalling pathways mediate biotic stress signals resulting in the activation of host defence responses. Piercing-sucking grape phylloxera (Daktulosphaira vitifoliae) infests Vitis spp. by the formation of organoid root galls. This study aims to investigate whether host defensive SA/JA signalling pathways are affected during D. vitifoliae infestation. We hypothesize that the JA signalling pathway is induced during larval probing (14 hai). Compatible root gall formation (24 hai − 14 dai) involves the reduction of the JA, but the induction of the SA signaling pathway. T5C (V. berlandieri x V. riparia) cuttings are infested with a D. vitifoliae single founder lineage (biotype C). Phytohormone quantification (HPLC-MS) and transcriptional alterations of JA/SA marker genes (qRT-PCR) are determined in root tissues from larval probing (14 hai) until gall formation (>14 dai). Non-infested root tips are considered controls. Our results show a significant induction of all analysed JA marker genes during insect probing (14 hai), but their significant reduction during early gall formation (24 hai). Following gall formation (5–14 dai) SA and JA-Ile increase. However, only the analysed SA marker genes are induced, whereas JA marker gene expression levels are significantly reduced. Based on this data we conclude that the observed suppression of the JA signalling pathway might represent an important step for the compatible D. vitifoliae – Vitis spp. root interaction. We discuss whether the induced SA defences protect nutritive root galls against soil microbes. • D. vitifoliae probing induces the JA signaling pathway on Vitis spp. roots. • Subsequent root gall formation involves the transcriptional suppression of the JA, but the induction of the SA signaling. • Induced SA defence responses might protect nutritive root gall tissue against soil microbes. [ABSTRACT FROM AUTHOR]

Guignardia bidwellii (anamorph Phyllosticta ampelicida) is the etiological agent of grape black rot, a disease of economic importance in Europe and a quarantine pest for Mexico. The identification of the anamorphic state by morphological characteristics is complicated, due to the similarity among species of the same genus, for example with the cosmopolitan endophyte G. endophyllicola (P. capitalensis), therefore it is necessary to have quick and specific diagnostic tools. For this purpose, a molecular marker based on single nucleotide polymorphisms (SNP) in the ITS region of the rDNA was developed, where the Bidwell and Ampel2 primers were designed. The PCR amplification generates a fragment of 173 bp, specific to G. bidwellii f. euvitis. The validation of the method showed that there is no cross amplification with closely related phytopathogenic fungi or with the genome of grapevine. The technique was sensitive to detect up to 30 pg μL-1 of DNA from monosporic cultures and in mixture of plant tissue. This diagnostic procedure is presented as a fast and specific option for the monitoring, and detection of G. bidwellii f. euvitis in support of prevention, management, quarantine and eradication strategies of the disease. [ABSTRACT FROM AUTHOR]

Abstract the aim of this study was to evaluate the chemical characteristics and sensory acceptance of juices and cuts of ‘Bordô’ and ‘Niágara Rosada’ grapes. The experimental design was in a one-factor scheme, with five levels. Treatments were: T1 – ‘Bordô’ (100%); T2 – ‘Bordô’ (70%) + ‘Niágara Rosada’ (30%); T3 – ‘Bordô’ (50%) + ‘Niágara Rosada’ (50%); T4 – ‘Bordô’ (30%) + ‘Niágara Rosada’ (70%); T5 – ‘Niágara Rosada’ (100%). Chemical analyses were: content of soluble solids, pH and titratable acidity, and sensory analyses were: color, aroma, flavor, body and global acceptance. For the soluble solids content, the highest averages were verified in T1, T2 and T3 treatments. As for pH, the highest value was recorded in T3, T4 and T5 treatments, while the highest titratable acidity was recorded in T4 and T5 treatments. In the sensory analysis, in juice with the highest percentage of ‘Bordô’ grape (T1 and T2) or with the same proportion of ‘Bordô’ and ‘Niágara Rosada’ (T3), the highest mean acceptance values were found. Thus, it could be concluded that the use of 100% ‘Bordô’ grape and ‘Bordô’ juice cut with up to 50% ‘Niágara Rosada’ are presented as alternatives for juice production.

ABSTRACTMealybugs (Hemiptera: Pseudococcidae) are important pests of the grapevine Vitis spp. and are responsible for direct and indirect damage to production. The main mealybug species present in wine grapevine (Vitis vinifera L.) in Southern Brazil were identified and their incidence evaluated. Bunch-samples (n = 50) from 131 vineyards located in the Serra Gaúcha Region (RS) of Brazil were analyzed at harvest, and the occurrence of mealybugs in the roots was evaluated at the time of eradication of plants for replanting. Mealybugs were reared in laboratory until adulthood for species determination. The species Dysmicoccus brevipes (Cockerell, 1983), Dysmicoccus sp., Planococcus citri (Risso, 1813), Pl. minor(Maskell, 1897), Pseudococcus viburni (Signoret, 1875) and Pseudococcus sp. were identified in bunches. Dysmicoccus sp., D. umbambae Granara de Willink, 2009, Pl. citri and Pseudococcus sp. were found in the roots. Pl. citri (31.4%) and Dysmicoccus sp. (22.7%) were the most common species found in wine grape bunches in the Serra Gaúcha Region.

Crop productivity is limited by phosphorus (P) and this will probably increase in the future. Rootstocks offer a means to increase the sustainability and nutrient efficiency of agriculture. It is known that rootstocks alter petiole P concentrations in grapevine. The objective of this work was to determine which functional processes are involved in genotype-specific differences in scion P content by quantifying P uptake, P remobilization from the reserves in the cutting and P allocation within the plant in three grapevine genotypes. Cuttings of two American rootstocks and one European scion variety were grown in sand and irrigated with a nutrient solution containing either high P (0.6 mM) or low P (0 mM). The high P solution was labelled with32P throughout the experiment. The grapevine genotypes studied show variation in the inhibition of shoot and root biomass in response to low P supply, and P supply also affected shoot, but not root, P concentrations. Genotype-specific differences in total P content were related to differences in P acquisition and utilization efficiencies (PAE and PUE, respectively). Phosphorus allocation within the plant was not affected by genotype or P supply. The rootstock genotype known to confer high petiole P content in the vineyard was associated with a high PAE under high P, and a high PUE under low P. This suggests that the petiole P concentrations in the vineyard are related to genotype-specific differences in PAE and PUE, and that these traits could be used for rootstock selection programmes in the future. [ABSTRACT FROM AUTHOR]

ABSTRACT: Cover crops may have direct or indirect effects on the physical and chemicalsoil attributes; these cropsplay a key role in the cycling of nutrients in the soil and add labile organic carbon, bringing economic and environmental benefits to the system. To study the effect of cover crops on the physical and chemical properties of an Oxisol, a three-year experiment was conducted in a commercial vineyard located at Epagri’s Experimental Station in Videira, SC, Brazil. Different winter species (white clover, red clover, common vetch, turnip, corn spurrey, black oat, rye, and ryegrass) were sown in addition to treatments with manual weeding or mechanical mowing. Certain chemical and physical attributes of soil were determined in samples collected fromlayers 0-0.1 and 0.1-0.2m deep on the vinerows and between rows, as well as the dry mass of winter cover crops. Few chemical and physical attributes of the soil changed among winter cover crops and did not differ from the crops managed with mechanical mowing or hand weeding of spontaneous vegetation. Vine rows provided more adequate values of most physical and chemical soil attributes.

‘BRS Nubia’ is a new seeded table grape with dark black color, high yield, neutral flavor, and crunchy large berries. However, this cultivar frequently presents very dense bunches, limiting its commercialization. The aim of this work was to obtain uniform and loose bunches of ‘BRS Nubia’ table grape by means of inflorescence and bearing shoot management associated to berry thinning. The trial was conducted during two consecutive seasons of 2015 and 2016, in a 2-year old commercial vineyard located in Marialva, Parana, Brazil. The vines were trained in an overhead trellis system and spaced at 2.5 × 9.0 m distance. The experimental design was randomized block with four replications in a 2-factor arrangement with two additional treatments (factorial 2 × 2 + 2). The following factors were evaluated: inflorescence management (with tipping before anthesis and without tipping), bearing shoot tipping (before or after anthesis), and two additional treatments consisted of two controls (with or without berry thinning). The berry thinning was performed in all treatments, except in control without berry thinning, by means of picking when berries were at pea size. Physico-chemical analysis of the berries as well as bunch compactness and yield were evaluated at harvest time. Means were subjected to analysis of variance and compared using Tukey’s test at 5% probability. Additionally, the Principal Components Analysis (PCA) was used to describe the relation of physico-chemical and productive characteristics of grapes with the inflorescence and shoot management. The inflorescence tipping before anthesis is a useful practice by facilitating and saving time to perform berry thinning of ‘BRS Nubia’ table grapes, while the bearing shoot tipping after the anthesis may accelerate the bunches ripening. Combined to these practices, berry thinning is a mandatory procedure in order to obtain medium loose bunches of ‘BRS Nubia’ table grape, with larger and uniform berries. [ABSTRACT FROM AUTHOR]

Detection of viruses in grapevine plants is important to prevent their spreading with propagating stocks. For this purpose PCR based protocols are commonly and routinely used. Since most grapevine viruses are RNA viruses, the detection procedure starts with RNA purification followed by cDNA synthesis prior to PCR. The cDNAs should be validated by an internal control for which usually constitutively expressed housekeeping genes are used. Here we publish a new set of primers designed in the Vitis vinifera phosphoenolpyruvate carboxylase gene to encompass two or three introns. PCR products amplified from remaining genomic DNA in the RNA samples and from cDNA can be clearly distinguished since cDNA-derived products are smaller in size compared to those amplified from genomic DNA. Thus these primers may be useful reference markers in RT-PCR-based virus detection assays both for the validation of cDNA synthesis and the detection of trace amounts of genomic DNA. [ABSTRACT FROM AUTHOR]

Anthropogenic influences such as tourism and climate change affect ecosystems. One consequence is that invasive species can spread to and colonize novel areas. A recent example of this scenario is the appearance, in the early 2000s in Brazil and Australia, of the plant pathogenic fungus Phakopsora euvitis, which causes Asian grapevine leaf rust. It is speculated that the disease was introduced either by long distance transport of spores in the atmosphere or the import of contaminated plant material. While the disease could be eradicated from the Australian continent it is still present in Brazil. The pathogen has spread successfully throughout most Brazilian grapevine-growing regions, most probably because of the lack of resistant plant cultivars. Today, the disease is endemic in Brazil. This review was written to highlight the increasing impact of the disease in Brazil and summarizes the current knowledge on the disease monocycle under different environmental conditions and the consequences for grapevine management. Gaps in the present state of knowledge are highlighted with the purpose of stimulating further research aimed at identifying efficient strategies to combat the disease. [ABSTRACT FROM AUTHOR]

Summary There is concern about the health problems caused by pesticides in humans, which has led some grape producers to adopt organic procedures in their vineyards, and a certain amount of these grapes are directed to winemaking. Despite the approval awarded to this organic grape production by the certified organizations, there has been a demand to carry out a survey to determine the physicochemical composition of the wine derived from these products. Some of these wines were made from a single grape variety and others from more than one. For this survey, the samples consisted of five bottles of each type of wine, acquired from wineries and supermarkets in the Serra Gaúcha region, RS, Brazil. The analyses were carried out by physicochemical methods: volatile compounds by gas chromatography; minerals and trace elements by inductively coupled plasma optical emission spectrometry; and pesticide residues by liquid chromatography-mass spectrometry. The results showed that in general the physicochemical composition of these wines was within the limits established by Brazilian legislation. The mineral and trace element concentrations were very low and pesticide residues were not detected (MRL = 10 μg.kg–1) in any of the wines.

Copyright of Journal of Viticulture & Enology / Ciência e Técnica Vitivinícola is the property of EDP Sciences 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.)

Plant growth and reproductivity of grape cv. 'Italia' subjected to two different irrigation levels in controlled glasshouse were investigated over 2 years. Initially, two years old vines were grafted on 5 BB (V. berlandieri Planch.⨰V. riparia Michx.), 99 R (V. berlandieri Planch.⨰V. rupestris Scheele) rootstocks or on its own root system in 40 L pots. During the cultivation, half of the vines of each experimental group were Fully Irrigated (FI: 100% of field capacity) while the others were subjected to continuous Deficit Irrigation (DI: 40% of field capacity). During the study, significant negative effects of DI on plant vegetative development and physiology were observed. The lignified shoot length of vine on 5 BB rootstock decreased by 29.1% under DI as compared to growth under FI. On the other hand, the vine with 99 R rootstock decreased by 18.2% under DI as compared to lignified shoot growth under FI, while a 20.1% decrease occurred for own root (DI vs. FI). Also, DI regime resulted in slight decreases in P, K, and Ca status of leaves, while Zn and Cu concentrations were significantly higher in the vines subjected to DI. DI resulted in reduced cluster weight and vine yield in varying degrees with respect to rootstock usage. Under DI condition, the vines on 99 R yielded better than those on 5 BB, but vines on on 5 BB reacted adversely to DI. Considering the overall findings, grapevines cv. 'Italia' on 99 R exhibited higher drought tolerance than 5 BB. Rootstocks had slight impairing effects on physiological traits, yield, and mineral acquisition of grapevine cv. 'Italia' as compared to own-rooted. [ABSTRACT FROM AUTHOR]

The vine is a culture in expansion in Brazil and Rio Grande do Sul State comprises the largest area planted with the crop. The vine is subject to attacks by numerous pathogens and pests, and plant protection treatments up to 30% of the production cost. Several studies are performed with the purpose to find alternative control, but the main method used is still the chemical control. Thus, the objective of this work was a survey the main fungicides and insecticides sold in agricultural and animal production stores of Bento Gonçalves city, Rio Grande do Sul State, Brazil, suitable for the vine culture in 2013. It was performed the survey in agricultural and animal production stores in 2014, with the completion of interviews, with a total of six agricultural and animal production stores consulted. The analyzes were performed by calculating the absolute and relative frequencies of the most marketed fungicides and insecticides associated to the main phytosanitary problems of the vine and the toxicological and environmental classes. All mentioned fungicides are registered for the vine culture and are used for the control of Plasmopara viticola, causing the mildew. In relation to insecticides, not all which were cited are registered, being a serious problem in the matter of residues in fruits. Most cited product belongs to toxicity class III and environmental class II. Among the products listed, the organophosphates and pyrethroid insecticides are not selective to natural enemies, and neonicotinoids are highly toxic to bees. [ABSTRACT FROM AUTHOR]

Copyright of Revista Caatinga is the property of Revista Caatinga 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.)

Copyright of Revista Ciência Agronômica is the property of Revista Ciencia Agronomica 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.)