Onions are a challenging crop to grow. Robust disease spray programmes are crucial to maximising marketable yield. Super protectant fungicide Ranman 400 SC delivers against downy mildew.
The novel chemistry shaking things up in onions
Onions are a challenging crop to grow. Pieter Van Der Westhuizen, UPL NZ Ltd Regional Manager Upper North Island, says robust disease spray programmes are crucial to maximising marketable yield.
“It’s getting that critical balance between the weather, disease pressure, fungicide cover and fungicide resistance. Onions need extensive weed control programs, that means there is the need for regular herbicide applications, which can stress and cause injury to the plants. That makes the onion crop vulnerable to fungal disease attack especially downy mildew (Peronospora destructor). Markets demand an unblemished product, so protection against downy mildew is essential."
Super protection against downy mildew with Ranman
Ranman 400 SC is a partially systemic translaminar super protectant fungicide that is highly active on oomycete fungi, i.e., downy mildew. A real unique feature of Ranman is that it inhibits all stages of disease development.
Pieter says in terms of preventing resistance, Ranman also provides a much-needed alternative chemistry partner, applied as part of a tight spray schedule (7-10-day intervals) in rotation with other chemical groups. Ranman’s novel chemistry (cyazofamid) from the FRAC 21 chemical group makes it a highly effective component for disease resistance management.
For more information on Ranman read here.
Ranman also allows growers to reduce the number of Mancozeb applications. “That’s crucial for export markets.”
Pieter says the product has other benefits too. Ranman has a high affinity to waxy surfaces of the crop and penetrates leaves almost immediately after application that means it is rainfast within one hour. “Front-footing the disease is important. Always apply Ranman early, whenever disease conditions are prevalent, and prior to the appearance of downy mildew.”
Adding an adjuvant is a must
He states that thorough plant coverage is critical. Ranman must always be applied with an adjuvant - Actiwett® in high water volumes, Du-Wett® in low water volumes.”
Ranman also provides excellent control of late blight on potatoes. It is active on all stages of the late blight life cycle and, as in onions, is an ideal resistance management tool. On potatoes, Ranman can be used early, to protect expanding leaves, mid-season on a stable canopy or late season for tuber protection. “It’s a great option.”
