Verticillium Wilt?

Choosing the right variety is the most important decision when dealing with Verticillium Wilt in cotton. Temperature and moisture are the two most important environmental factors that contribute to the spread of Verticillium Wilt. Also, once levels build up in the soil over a period of time, there is nothing that can be done to alleviate this disease. The critical point of disease development is late in the production season when soil temperatures start to decline, and plants begin to mature in August and September. Varietal response within our FiberMax and Stoneville varieties give us crucial information for placing specific varieties on fields with incidences of Verticillium Wilt.

Each year we evaluate new experimental lines as well as current commercial varieties to determine the tolerances of each. When symptoms start to appear towards the end of the growing period, two critical ratings are taken each week over a period of three to four times.

This is the first evaluation observed from the slide above that shows the amount of chlorosis on the leaves of each plant (bars in %infected) as well as the number of plants that have defoliated (red line % infected) within a 25-plant sub sample.

Drone data is also evaluated across the entire APT. A ranking of 1 in a light tan is a low defoliation of a variety up to a black color of 16, which is a high defoliation of a variety.

Knowing the tolerance levels of our cotton portfolio continues to help our Agronomic Seed Advisors place great yielding varieties in areas where Verticillium wilt is present.