Big vein
Lettuce big vein virus
What is Big vein (Lettuce big vein virus)?
Big vein disease is a soilborne viral disease transmitted by the oomycete (Olpidium virulentus). Symptoms include enlarged leaf veins with clear areas, puckered and mottled leaves, and failure of head formation. The disease is prevalent in wet, cool conditions They have been detected in lettuce, garland chrysanthemum, tomato, eggplant (MLBVV), onion, Welsh onion, and Chinese chive.
How does the Big vein (Lettuce big vein virus) occurs?
Big vein disease occurs through the transmission and reproduction of viruses by the soilborne oomycete, Olpidium virulentus. The oomycete attaches itself to lettuce roots, introducing the viruses. The viruses can survive in the soil for several years within resting sporangia. When uninfected oomycete strains encounter infected plants, they acquire viruses, continuing the cycle of transmission. The disease can also spread through weedy hosts acting as reservoirs for the oomycete and viruses.
Symptoms
1 - Effects on Plants
The disease can cause stunted growth, resulting in reduced yield potential. Big vein disease can affect the overall quality and marketability of lettuce and related crops.
3 - Effects on the Environment
Big vein disease affects various plant species, potentially impacting crop diversity and ecosystem dynamics.
Solutions
1 - Avoid Early Planting in Wet Soil and Long Rotations
• Refrain from planting lettuce and other susceptible plants, early in wet soil or poorly draining fields with a history of the disease. • Wet and cool conditions promote disease spread. • Implement long crop rotations on heavily infested land. • Avoid planting lettuce or susceptible crops in the same field for an extended period.
2 - Residue Management and Disease-Free Land
• Remove and dispose of crop residue instead of incorporating it into the soil. • Prevents pathogen buildup and persistence. • Choose land not previously planted with lettuce, if possible.
3 - Soil Steam Treatment
• In seedbeds or greenhouse settings, steam treatment of the soil can be effective in reducing the population of the vector (Olpidium virulentus) and the associated viruses. • This can help create a healthier planting environment and reduces disease incidence.
