High cotton yields begin with healthy, uniform stands. Fungal pathogens like rhyzoctonia and pythium reduce stand counts, seedling vigor, yields and profits.
Today’s cotton seed treatments are the first line of defense against disease causing fungi. In this article we will look at various seed treatment options and practices which can reduce losses from seed and seedling diseases.
Cotton seed treatments are a mix of at least two fungicides. Different chemistries control different classes of fungi. Using two to three fungicides in your seed treatment gives a broad range of control.
For example, the active ingredient in Ridomil and Apron is used to control pythium. The addition of Maxim to Apron broadens the spectrum of control to include rhizoctonia, sclerosium rolfsi , and various rots. Mixes like RTU Baytan, Thiram perform similarly with Baytan controlling rhizoctonia and Thiram controlling pythium.
Most seed treatment combinations will contain at least one ingredient for pythium control and one for rhizoctonia. Other products that control pythium include Allegiance and Dynasty, while Argent and NuFlow M are other treatments applied for rhizoctonia .
Do I need an in-furrow treatment? Twenty five years ago the easy answer to that question was ABSOLUTELY. Today, the answer is probably not unless you have very high disease pressure. If you grow cotton behind cotton for several years without rotation and have a history of stand loss and replanting, then in-furrow products may have a fit for you, but most cotton acreage will be planted without one.
Growers can also protect themselves from seedling disease by choosing their planting window carefully. By planting when soil temperatures are predicted to remain at least 60 F in the top two inches for three consecutive days, emergence is optimized and seedling diseases have less opportunity to affect vigor and yield. The forecast should also be checked for heavy rains in the next five day period. The goal is to avoid your seeds imbibing cold water from the surrounding soil.
Another key element to avoiding stand loss is to know everything you can about your seed. While you may not always be able to get the cool germ you want, knowing what cool germ you have is critical. If logistical constraints force you to plant when conditions are less than perfect, it helps to know which seed lots are most likely to perform under adverse conditions. The cool germ is still your best indicator for performance in cooler soils.