Crops
Protection methods
- During cultivation
Unlike the majority of cryptogamic diseases, there is no curative control method making it possible to effectively control the viruses during cultivation and in particular the Mirafiori lettuce big vein virus (MLBVV). An infected plant will remain so for its entire life.
During and at the end of cultivation, plant debris , in particular root systems, must be removed from the plots and destroyed, in order to prevent them from being subsequently buried in the soil at the same time as the resting spores. Olpidium virulentus .
- Next crop
should be Healthy plants planted to avoid introducing MLBVV into soils that are still free.
The nursery soil should be disinfected with a fumigant . It will also be beneficial to place the plants produced on tables or a plastic film in order to avoid contact of the roots formed with the soil.
Eradication of the disease in a given plot is almost impossible since the resting spores of the fungus vector retain their ability to transmit the virus for 15 to 20 years. Also, contaminated soil will remain so for a long time. The soil of future salad plots will be well prepared and drained in order to avoid the formation of puddles favorable to the development and dissemination of Olpidium virulentus . It will be better to plant salads on hillocks. Under shelter, fumigation of the soil may be considered, in order to limit the number of viruliferous resting spores in particular. The effectiveness of this treatment can last 2 to 3 years, when it is carried out according to the rules of the art.
No high level Big-vein resistance was found in salads. In the United States, a few varieties of iceberg with less sensitivity have been released; the variety "Pacific" being considered as the most tolerant. Field trials in Europe have not confirmed these behaviors. Currently, the selection of resistant plants is done by simple observation of the symptoms present on salad genotypes cultivated and screened in contaminated soil. This method is very random, because of the strong influence of temperature and environmental conditions on the expression of symptoms. No resistant material is available in other types of lettuce.
A good level of resistance has been found in some accessions of L. virosa , but it is not known whether this is resistance to the virus or to the vector.
The availability of a serological test for MLBVV should make it possible to re-consider the evaluation of resistance to this virus in Lactucae sativa and in other species. On the other hand, studies on the level of receptivity of lettuce roots to Olpidium virulentus are currently being carried out in Europe.
Unlike the majority of cryptogamic diseases, there is no curative control method making it possible to effectively control the viruses during cultivation and in particular the Mirafiori lettuce big vein virus (MLBVV). An infected plant will remain so for its entire life.
During and at the end of cultivation, plant debris , in particular root systems, must be removed from the plots and destroyed, in order to prevent them from being subsequently buried in the soil at the same time as the resting spores. Olpidium virulentus .
- Next crop
should be Healthy plants planted to avoid introducing MLBVV into soils that are still free.
The nursery soil should be disinfected with a fumigant . It will also be beneficial to place the plants produced on tables or a plastic film in order to avoid contact of the roots formed with the soil.
Eradication of the disease in a given plot is almost impossible since the resting spores of the fungus vector retain their ability to transmit the virus for 15 to 20 years. Also, contaminated soil will remain so for a long time. The soil of future salad plots will be well prepared and drained in order to avoid the formation of puddles favorable to the development and dissemination of Olpidium virulentus . It will be better to plant salads on hillocks. Under shelter, fumigation of the soil may be considered, in order to limit the number of viruliferous resting spores in particular. The effectiveness of this treatment can last 2 to 3 years, when it is carried out according to the rules of the art.
No high level Big-vein resistance was found in salads. In the United States, a few varieties of iceberg with less sensitivity have been released; the variety "Pacific" being considered as the most tolerant. Field trials in Europe have not confirmed these behaviors. Currently, the selection of resistant plants is done by simple observation of the symptoms present on salad genotypes cultivated and screened in contaminated soil. This method is very random, because of the strong influence of temperature and environmental conditions on the expression of symptoms. No resistant material is available in other types of lettuce.
A good level of resistance has been found in some accessions of L. virosa , but it is not known whether this is resistance to the virus or to the vector.
The availability of a serological test for MLBVV should make it possible to re-consider the evaluation of resistance to this virus in Lactucae sativa and in other species. On the other hand, studies on the level of receptivity of lettuce roots to Olpidium virulentus are currently being carried out in Europe.