With the registration of Maxim 480 FS seed treatment, growers have been asking how the different seed treatments compare for disease control. In seed treatment trials conducted at the Delhi Research Station, Maxim provided the comparable or improved efficacy against soil-borne diseases of ginseng compared to other unregistered seed treatments including Senator. A combination of Apron and Maxim, the only two seed treatments registered for use on ginseng, provides broad-spectrum disease protection. These products are only registered for one application to the seed after stratification. These seed treatments must be applied at a commercial seed treatment facility.

With the registration of ScalaSC fungicide, ginseng growers now have a number of options for control of Alternaria and Botrytis. The choice of a fungicide will depend on the cost, the spectrum of diseases controlled, and the efficacy of the product. However, growers should always keep in mind that these products must be rotated to avoid the development of resistance. If resistance develops, a valuable disease management tool could be lost forever.

Scala SC fungicide is in Group 9, the same group as one of the components of Switch 62.5 WG. If both of these products are in the spray rotation, a third product from a different group should be applied between Scala and Switch applications. For Scala, a rotation that includes at least two other fungicides is recommended. The remaining products registered for use on Alternaria and Botrytis are in different groups, so rotation between any of these products would help to avoid the development of resistance. It is important to remember that products applied for Phytophthora or any root disease cannot be considered as part of the resistance management program for Alternaria and Botrytis, since they have minimal effect on these diseases.