With a new season beginning, growers are starting to apply products for disease control on ginseng. Here are the changes in pest control products since last spring.
Nematode Control
Velum Prime (fluopyram) is now registered for control of soil dwelling/root feeding nematodes. It is best applied at seeding and in the spring of the seedling year. The optimal time for spring application is before or during seed germination. Research has shown that root lesion nematodes are at very low levels beyond the seedling year and there is likely no benefit to applications of nematicides to older gardens.
Velum Prime should be applied at 500 ml/ha. Do not exceed 500 g of fluopyram in a single year (=2 applications of Velum Prime). Luna Sensation also contains fluopyram and must be factored into the maximum applications permitted per year. REI = 12 hr, PHI = 7 days. Consult the label for more information.
Disease Control
Miravis Duo is now registered for control of Alternaria on ginseng at a rate of 1 L/ha. Maximum applications are 4 per year. REI = 12 hr. PHI = 7 days. Miravis Duo contains a mix of a Group 3 (difenoconazole) and Group 7 (pydiflumetofen) fungicide. Rotate out of Group 3 and 7 after two consecutive applications of Miravis Duo
Merivon is now registered for control of Alternaria on ginseng at a rate of 300-400 mL/ha. Maximum applications are 3 per year. REI = 7 days for harvest, 12 hr for all other activities. PHI = 7 days. Merivon contains a mix of a Group 7 (fluxapyroxad) and Group 11 (pyraclostrobin) fungicide. If possible, rotate out of these two groups after every application. Otherwise, do not apply more than twice in a row. Note: fluxapyroxad is the same active ingredient as Sercadis fungicide.
Re-evaluations
The following re-evaluations that affect ginseng are now fully in effect:
- Captan products (Maestro, Captan, Supra Captan) – REIs have now changed to 7 days for setting up hand-set irrigation, 4 days for hand harvesting and 12 hr for all other activities. New use precautions are also in effect. Consult label.
- Chlorothalonil products (Bravo, Echo) – Maximum 2 applications during the season + one application in the fall. REI is now 12 hr. New use precautions are also in effect. Consult label.
- Iprodione (Rovral) is now fully de-registered and illegal to apply to ginseng.
Mancozeb products (Manzate, Dithane, Penncozeb). PMRA recently published its final decision on re-evaluation of mancozeb products. There are no proposed changes to the use pattern for ginseng and ginseng will retain 6 applications per year. Additional use precautions may apply. Consult updated labels once they are finalized.