Biological control of Agrobacterium vitis using non-tumorigenic agrobacteria

The potential use of non-tumorigenic agrobacteria for the biological control of grapevine crown gall in Italy was investigated. Four Agrobacterium strains belonging to the species radiobacter and vitis were used to protect the susceptible cv. Malvasia Istriana grafted on the rootstock 420 A. Moreover, the effect of each treatment on grapevine vitality and growth was assessed, including the percentage of marketable vines, as determined by industry standards. Treatments with the antagonists clearly reduced tissue colonization by the pathogen, with a drop of more than 100-fold in pathogen populations in the samples collected at the graft point. Another important effect was the reduction of internal necrosis possibly induced by the high concentration of the nopaline strain CG 49 used in the experiments. According to viticultural and commercial parameters, treatments with the antagonists improved the quality of the vines, with fewer discards and a high percentage of marketable material. Therefore, these antagonists can be considered beneficial for grapevine

Effect of bioagents and resistance inducers on grapevine crown gall

Bioagents and chemicals were applied to one-year old grafted vines (Ancelotta/420A) in glasshouse and field experiments set up at the Vivai Cooperativi Rauscedo (VCR, Pordenone, Italy). In the glasshouse, holes were drilled in vines on the rootstock and the holes were charged with suspensions of different strains of Pseudomonas spp., and with the biofungicides BS-F4 and Serenade, both based on Bacillus subtilis, before inoculation with a vitopine Agrobacterium vitis strain. The growth retardant Regalis and the resistance inducer Bion were applied to the vines two weeks before inoculation with the pathogen. Six months after inoculation, disease incidence was lowest when BS-F4 had been applied. In the field trial, the vines were wounded by making a cut in the crown, after which they were dipped into the antagonist suspensions just before inoculation with the pathogen. In the two weeks before inoculation, the root systems of the vines were dipped into Regalis and Bion solutions at 7 day intervals. Only these resistance inducers and BS-F4 significantly reduced disease severity. The results indicate that a potential for defence against A. vitis may exist even in susceptible grapevine cultivars, and that this potential can be activated by diverse elicitors

Hot-water treatment of dormant grape cuttings: Its effects on Agrobacterium tumefaciens and on grafting and growth of vine

Hot-water treatment (50°C for 20-30 min) was carried out to confirm its efficacy in eradicating Agrobacterium tumefaciens biovar 3 (AT3) in symptomless grape cuttings.After the forcing period, analyses of callus from cuttings of grape cvs Albana, Lambrusco Grasparossa, Rulander and Fortana, and from their graft combinations with the rootstocks 420A, 41B, 5BB and 1103P, revealed the low infection level in the grape material used. Dormant scion and rootstock cuttings treated identically in the U.S. gave similar results. Despite this, it was possible to confirm the efficacy of thermotherapy in eradicating the pathogen.An assessment was also made of the effect of treatment on growth parameters of grafted vines in the greenhouse and after 8 months in a field nursery. The effect of hot-water treatment on the vitality and growth of vines varied with the different scion-rootstock combinations. Treatment did not generally have detrimental effects on vitality; there were some negative effects on graft-take. The number and length of canes, as well as the diameter of the trunks, increased in most instances.The treatments and times usually did not affect bud survival and, in most cases, increased the level of callus formation at the base of cuttings.

Altered two-dimensional strain measures of the right ventricle in patients with Brugada syndrome and arrhythmogenic right ventricular dysplasia/cardiomyopathy

Aims: Brugada syndrome (BrS) is an inherited channelopathy that can be characterized by mild right ventricular (RV) abnormalities that are not detectable with conventional echocardiography. The aim of this study was to evaluate the presence of RV abnormalities in BrS patients when compared with controls and a group of patients with arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) using two-dimensional (2D) strain analysis. Methods and results: We enrolled 25 BrS, 15 ARVD/C patients, and 25 controls. Right and left ventricular dimension and systo-diastolic function were evaluated by conventional echocardiography. Longitudinal systolic strain (sS) peak, systolic and early diastolic strain rate of lateral RV segments were evaluated by 2D speckle tracking analysis. Left ventricle global and segmental strain measures were also evaluated. A reduced basal or mid-RV lateral sS were the parameters mostly associated with both BrS and ARVD/C. In BrS patients the minimum sS observed in these segments was significantly lower than that of controls (-28.9±3.2% vs. -32.3±3.2%, P: 0.002) but significantly greater than that evaluated in ARVD/C patients (-24.6 ±6.7%, P < 0.001 both vs. BrS and controls). No differences were found between the BrS and the control group when left ventricular strain measures were analysed. Conclusion: By 2D strain technique it is possible to observe mild abnormalities in RV systolic and diastolic function of BrS patients that are less pronounced than those observed in ARVD/C patients. These results help to better define the phenotypic characteristics of BrS patients and represent the basis for future studies aimed at testing their clinical usefulness in BrS patients

Inter-varietal structural variation in grapevine genomes

Grapevine (Vitis vinifera L.) is one of the world's most important crop plants, which is of large economic value for fruit and wine production. There is much interest in identifying genomic variations and their functional effects on inter-varietal, phenotypic differences. Using an approach developed for the analysis of human and mammalian genomes, which combines high-throughput sequencing, array comparative genomic hybridization, fluorescent in�situ hybridization and quantitative PCR, we created an inter-varietal atlas of structural variations and single nucleotide variants (SNVs) for the grapevine genome analyzing four economically and genetically relevant table grapevine varieties. We found 4.8 million SNVs and detected 8% of the grapevine genome to be affected by genomic variations. We identified more than 700 copy number variation (CNV) regions and more than 2000 genes subjected to CNV as potential candidates for phenotypic differences between varieties. � 2016 The Authors The Plant Journal � 2016 John Wiley & Sons Lt

Relazioni tra l'anomalo ingrossamento dell'innesto in barbatelle di vite e lo stress ossidativo

The appearance of anomalous swellings in the graft zone of 1-year-old bench grafts is a drawback that often endanger the correct functionality of the vines and causes remarkable economic losses to grapevine nurseries. In several graft combinations characterised by different susceptibility to this hyperplasia, the activities of the main enzymes involved in oxidative stress defence were measured. Some of the enzme activities well correlated with the disorder incidence and differences in activity were detectable up to two months before the anomalous swellings were visible in the field