The real-time PCR detection system for grapevine yellows phytoplasmas described here is composed of two assays for group-specific detection of flavescence dorée (FD) and bois noir (BN) phytoplasmas and a universal phytoplasma assay. It uses hydrolysis minor groove binder probes (TaqMan-MGB). The addition of an assay for amplification of plant DNA co-extracted with phytoplasma DNA provides a further quality control for the DNA extraction and PCR amplification for each sample. The detection system described is reliable, specific, sensitive, and easily applicable to fast, high-throughput diagnosis of grapevine yellows phytoplasmas. In addition to the detection system, an approach for the quantification of phytoplasmas in the sample is described.
COBISS.SI-ID: 2614351
Grapevine Flavescence dorée yellows is caused by quarantine phytoplasma 'Ca. Phytoplasma vitis', is steadily spreading in Slovenian vineyards, and is occurring in all three wine regions in varying degrees. In order to carry out more focused field work, and due to its extensiveness, satellite images of the entire demarcated area in Primorska region and part of the demarcated area in Dolenjska region, were acquired in August and September 2012. Recordings were made by the satellite WorldView 2, which’s high spatial and spectral resolution enables object distinction on earth’s surface. First results of analyses performed on a limited dataset are presented. At the time of satellite recording, vine plants in the vineyards under study were attributed depending on visible signs of disease. Based on unique electromagnetic reflections from the objects we separated ground, vineyard row space and potentially infected plants. To identify potentially diseased plants we used several indices, calculated from reflections at different avelengths. The suitability of each index was tested with a one-way analysis of variance (ANOVA). Statistically significant differences between healthy and plants with different disease signs were found in certain indices. The applicability of these indeces was illustrated in more detail for two of them, both with statistically significant differences between healthy and diseased plants (p(0,001). Individually indexes were not capable to differentiate plants with different disease signs in a useful manner. However, using an algorithm that combines several indices, overall accuracy reached approximately 70%. In future analyses we plan to employ new methods, such as machine learning.
COBISS.SI-ID: 4315240
Scaphoideus titanus Ball is a leafhopper natural vector of the phytoplasma that causes “flavescence dorée” (FD), the most important vector grapevine yellow diseases. One of the main phytosanitary measures to prevent the spread and control of FD is successful protection against the leafhopper Scaphoideus titanus. For this measure is needed knowledge of bionomics. Bionomic characteristics of leafhopper S. titanus were monitored and studied in growing chamber and in vineyards. Under growing chamber conditions were assessed the hatching of leafhopper S. titanus larvae on the biennial shoots of grapevine which were collected in three different vineyard regions of Slovenia. At temperature 23 °C, 70 % relative humidity and 15-hour day length, leafhopper S. titanus larvae hatched more that 67 days. The maximum development had second larvae stage (L2), in average of 11 days. Leafhopper S. titanus development was also monitored in vineyards in the area Šmarsko - Virštanj region by visual inspection of vine leaves and using yellow sticky traps. Results of the research will assist in leafhopper S. titanus control strategies.
COBISS.SI-ID: 597388
Grapevine quarantine disease Flavescence dorée (FD) may affect large areas of vineyards and cause significant yield losses. In Slovenia, it was confirmed for the first time in 2005; since 2009, it has been confirmed in all Slovenian wine-growing regions. Significant outbreaks have been recorded at Dolenjska and Primorska. New findings in 2011 show that this dangerous disease has been spreading in Slovenia; therefore, implementation of strict measures is needed to prevent economic damage. The phytoplasma FD spreads through infected planting and propagation material of Vitis and insect vectors. Its main natural vector is American leafhopper Scaphoideus titanus, which transmits the phytoplasma by moving from vine to vine to feed. There are only a few data about other potential plant hosts and vectors of the FD phytoplasma; however, such data is needed for an efficient control of the disease. Therefore, in this paper, besides the new data about FD distribution in Slovenia and new possibility of the disease control, the current knowledge about alternative plant hosts and vectors is presented.
COBISS.SI-ID: 29453017