Projects / Programmes source: ARIS

Molecular basis of grapevine yellows and induced resistance to the disease

Research activity

Code Science Field Subfield
4.03.00  Biotechnical sciences  Plant production   

Code Science Field
T490  Technological sciences  Biotechnology 
Phytoplasma, Vitis vinifera, gene expression profiling, cytokinins, sugar metabolism, oxidative stress, bioinformatics
Evaluation (rules)
source: COBISS
Researchers (7)
no. Code Name and surname Research area Role Period No. of publicationsNo. of publications
1.  06989  PhD Andrej Blejec  Mathematics  Researcher  2008 - 2011  287 
2.  08280  PhD Marina Dermastia  Biology  Researcher  2008 - 2011  872 
3.  15456  PhD Jasna Dolenc Koce  Biology  Researcher  2008 - 2011  217 
4.  12688  PhD Kristina Gruden  Biotechnology  Head  2008 - 2011  985 
5.  23606  PhD Matjaž Hren  Biology  Researcher  2008 - 2010  114 
6.  04333  PhD Maja Kovač  Biotechnology  Researcher  2008 - 2009  204 
7.  05229  PhD Maja Ravnikar  Biotechnology  Researcher  2008 - 2011  1,369 
Organisations (2)
no. Code Research organisation City Registration number No. of publicationsNo. of publications
1.  0105  National Institute of Biology  Ljubljana  5055784  13,256 
2.  0481  University of Ljubljana, Biotechnical Faculty  Ljubljana  1626914  66,295 
Phytoplasmas are cell wall-free bacterial plant pathogens in the Mollicutes class that are associated with over 1,000 plant diseases worldwide, including the grapevine yellows (GY). Typical symptoms of GYs are leaf rolling and discoloration of veins and laminas, uneven or total lack of lignification of canes, flower abortion and berry withering. Eventually, a severe decline and potentially death of sensitive grapevine varieties occur resulting in a serious decrease of quality and yield. The main phytoplasmas associated with GYs in European vineyards, including Slovenia, are phytoplasma “Flavescence dorée” (FDp) that causes the quarantine devastating disease of grapevine; and phytoplasma “Bois Noir” (BNp), which is already epidemic in Slovenia. Due to the inability to culture phytoplasmas in artificial media in vitro their physiological and genetic characteristics as well as mechanisms of phytopathogenicity or recovery/resistance remain poorly understood. The aims of the proposed work are therefore to gain better knowledge about the interaction between the grapevine and the FDp/BNp. Our goals will be attained using the approaches of genomics, transcriptomics, proteomics and metabolomics and will include a comprehensive analyses of the expression patterns of genes chosen from the previous microarray study on the basis of their involvement in the physiology of diseased plant; a biochemical study of the specific enzymes involved in the sugar metabolism; a biochemical study of the specific enzymes and compounds involved in the oxidative stress; a biochemical study of plant hormones cytokinins, putatively involved in pathogenesis. Some genes recognized to be involved in the process of pathogen infection and plant recovery might prove to be useful markers for early detection of the disease or its recovery, markers for good agronomical practice to avoid infection or to stimulate recovery, and possible targets for biological control of the disease. The results of this research therefore will be of great agronomical importance in attempts to lower the expenses for eradication of infected vineyards and in helping in controlling the health of planting material. Moreover, they will also provide the basis for understanding other diseases caused by phytoplasmas. The contents of the proposed research is in the EU Strategic Research Agenda and the first priority of the current public call with the emphasis on the genomics and biotechnology for health, quality and safety of food and sustainable development.
Significance for science
Our field conducted study revealed complex interactions among grapevine cv. 'Chardonnay' and 'BN' phytoplasma and thus substantially contribute to the understanding of still largely unknown mechanisms of phytoplasma patogenicity. The obtained results indicate that the phytoplasma infection induced both, the reprogramming of the primary metabolic pathways, as well as the activation of the secondary ones, possibly related to the defense mechanisms, and thus support the hypothesis that metabolic reprogramming is one of the plants' defense strategies against their pathogens. The gene expression changes in response to infection by phytoplasmas may support phytoplasma nutrition by promoting alterations in host's sugar metabolism. In addition, the induction of defense related pathways is in line with the hypothesis that defense compounds are induced in resistant as well as in susceptible interactions, with the main difference being in the speed and intensity of the response. The outcome of this study will likely impact not only the fundamental aspects of grapevine interactions with its pathogens, but also grape improvement, for example by yielding marker genes that can be used in new diagnostic assays for phytoplasmas or by identifying candidate genes that contribute to the improved properties of grape. The widespread BNf causes the same symptoms as a devastating one FDf. In accordance with this assumption we use it as a model for the FDf studies. These are exceptionally difficult because of the quarantine status of FDf, which requires an immediate destruction of all infected plants.
Significance for the country
The application of approaches developed in this study will contribute not only to better understanding of pathogenesis, but also to healthier agronomical important crops, like grapevine, and consequently to lowering the expenses for eradication of infected vineyards and improved yield and quality of wine. As a reference laboratory of the Phytosanitary Administration of Republic of Slovenia we already carry out the phytoplasma diagnostic as a part of the official phytopalsma survey. We are also advisors for the Phytosanitary Administration and inspectorates in cases of phytoplasma outbreaks and in preparation of the sanitary measures against grapevine yellows. With public lectures, broadcasts and popular papers we inform the general public with the problems of grapevine yellows.
Most important scientific results Annual report 2008, 2009, final report, complete report on dLib.si
Most important socioeconomically and culturally relevant results Annual report 2008, 2009, final report, complete report on dLib.si
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