Older leaves on tomato plants infected with Verticillium appear as yellow, V-shaped areas that narrow from the margin. The leaf progressively turns from yellow to brown and eventually dies. Older and lower leaves are the most affected. Sun-related fruit damage is increased because of the loss of foliage. A light tan discoloration develops in the vascular tissue, especially near the base of the plant. The discoloration extends a short distance up the plant and may occur in patches. Symptoms are most noticeable during later stages of plant development when fruit begin to size.
Verticillium wilt can be a devastating infection for a tomato crop. This fungal infection comes from the soil and it cannot be treated with fungicides. The best way to avoid it is to use resistant tomato varieties. It is also important to know the signs of the disease to avoid spreading it from one area to another. Infected plants should be removed from the field or greenhouse and burned instead of being put in the compost pile. Start new, disease free seedlings to avoid reintroducing verticillium wilt.
Once the plot is infested by Verticillium the harvest is lost in most cases.
I was planting 1200 tomato plants in my 512 m² glasshouse. I use that glasshouse since many years and the soil quality is poor. Suddenly, in January 2017 I recognized the infestion of Verticillium wilt by turning green leaves to yellow.
On the January 29, 2017 I applied 50g Sanbio EPSOMIT diluted in 50 L water (resp. 1kg/ha product rate) as foliar spray.
Figure 1. Leaves change their color, a symptom of Verticillium wilt, picture was taken on 2017-01-29 before treatment
Figure 2. The disease is spreading, picture was taken on 2017-01-29 before treatment
Figure 3. The plants are recovered and have a number of fruits, picture was taken on 2017-03-13, 43 days after treatment
Figure 4+5. Well-developed plants and fruits, pictures were taken on 2017-03-13, 43 days after treatment
Figure 6. The activator Sanbio EPSOMIT has rescued my harvest.
Figure 7. Yield per glasshouse (t)
“Just few weeks after the treatment the color of leaves changed to green. The vigor of plants has been improved and they became strong. Due to enlarged root mass their access to nutrient and water was improved. Furthermore, due to introduction of biotic and abiotic resistance there was no disease or stress-related weakness anymore. I achieved 1.5 tonnes higher harvest compared to the infested and untreated glasshouse. The harvested tomatoes have good quality. The activator Sanbio EPSOMIT has rescued my harvest.” Mejdi Zebidi