The proanthocyandin composition of skins and seeds of Bordeaux Merlot (M) and Cabernet Sauvignon (CS) grapes was evaluated by HPLC-UV-fluorescence for four consecutive vintages (2006 to 2009). The results indicated a strong vintage effect on the tannin profile of each variety. However, and in spite of the vintage effect, some tannin characteristics such as mDP, %G and %P allow discrimination of...

The Raspberry ringspot virus (RpRSV), first reported in raspberries (Rubus idaeus) in Scottland, is also a causative agent in Germany of the grapevine fanleaf disease and the Pfeffinger disease of sweet cherries. The RpRSV belongs to the genus nepovirus in the Comoviridae family, has polyhedral particles and is transmitted in the soil via nematodes. Different strains of RpRSV have been identifi...

BACKGROUND AND AIMS In spite of the abundance of archaeological, bio-archaeological, historical and genetic data, the origins, historical biogeography, identity of ancient grapevine cultivars and mechanisms of domestication are still largely unknown. Here, analysis of variation in seed morphology aims to provide accurate criteria for the discrimination between wild grapes and modern cultivars a...

It has been suggested that respiratory stress is involved in the mechanism underlying the dormancy-breaking effect of hydrogen cyanamide (H2CN2) and sodium azide in grapevine buds; indeed, reductions in oxygen levels (hypoxia) and inhibitors of respiration promote bud-break in grapevines. In this study, we showed that, hypoxia increased starch hydrolysis soluble sugar consumption and up-regulat...

Accurate localization of phytoalexins is a key for better understanding their role. This work aims to localize stilbenes, the main phytoalexins of grapevine. The cellular localization of stilbene fluorescence induced by Plasmopara viticola, the agent of downy mildew, was determined in grapevine leaves of very susceptible, susceptible, and partially resistant genotypes during infection. Laser sc...

Plants are colonized by diverse assemblages of fungal endophytes that have potential as biocontrol agents for a variety of crops, including grapevine. Although the diversity of symbionts can be very high in wild plants, the fungal endophytes of wild Vitis plants have not yet been investigated. We surveyed the fungal endophytes of 6 wild populations of Vitis riparia, as well as a cold-tolerant, ...

Grapevine leaf synthesizes a wide variety of bioactive secondary metabolites, including polyphenols, which are also key components in ensuring development and growth of the whole plant even under adverse environmental conditions. Our study evaluates the nonanthocyanin polyphenolic composition in grapevine leaves of three varieties of Gohér conculta (Vitis vinifera L.) native to Hungary. A high ...

For some crops, the only possible approach to gain a specific trait requires genome modification. The development of virus-resistant transgenic plants based on the pathogen-derived resistance strategy has been a success story for over three decades. However, potential risks associated with the technology, such as horizontal gene transfer (HGT) of any part of the transgene to an existing gene po...

Grapevine Algerian latent virus (GALV) is a member of the genus Tombusvirus in the Tombusviridae and infects not only woody perennial grapevine plant but also herbaceous Nicotiana benthamiana plant. In this study, we developed GALV-based gene expression and virus-induced gene silencing (VIGS) vectors in N. benthamiana. The GALV coat protein deletion vector, pGMG, was applied to express the repo...

Intracellular reproductive manipulators, such as Candidatus Cardinium and Wolbachia are vertically transmitted to progeny but rarely show co-speciation with the host. In sap-feeding insects, plant tissues have been proposed as alternative horizontal routes of interspecific transmission, but experimental evidence is limited. Here we report results from experiments that show that Cardinium is hor...