European Journal of Plant Pathology (2010) 127, 557-570

Giorgio Gambino, Rosalina Vallania and Ivana Gribaudo (2010)
In situ localization of Grapevine fanleaf virus and phloem-restricted viruses in embryogenic callus of Vitis vinifera
European Journal of Plant Pathology 127 (4), 557-570
Abstract: In grapevine, somatic embryogenesis is particularly effective in eliminating several important virus diseases. However, the mechanism whereby regenerated somatic embryos are freed of the viruses is not clear. The distribution of Grapevine fanleaf virus (GFLV), Grapevine leafroll-associated virus-3 (GLRaV-3) and Grapevine virus A (GVA) in embryogenic callus of grapevine was investigated by in situ hybridization using digoxygenin-labelled oligonucleotide probes. Four months after culture initiation, in callus originated by GFLV-infected explants we observed a mosaic of infected and uninfected cells, with high concentrations of viruses in some cell groups in peripheral zones of the callus. In addition some abnormal somatic embryos showed a high hybridization signal. In callus originated by GVA- and GLRaV-3-infected explants the viruses were concentrated in few cells surrounded by areas of virus-free cells. The two viruses were generally localized in different clusters of cells inside the callus and the levels of infection were lower than those observed in GFLV-infected callus. No virus was detected in callus nor in somatic embryos after 6 months of culture. The results highlight the difficulties of some viruses at stably invading callus tissues and the differential ability of GFLV to spread in the callus cells compared to the phloem-limited viruses.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): Ivana Gribaudo

Research topic(s) for pests/diseases/weeds:
general biology - morphology - evolution

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Nepovirus foliumflabelli	Grapevine (Vitis)
	Grapevine virus A	Grapevine (Vitis)