The saying goes, “April showers bring May flowers.” However, April showers also can bring May disease. The spring season is a critical time to begin prevention measures for disease pressures. Taking control early in the season can help prevent the establishment of devastating diseases such as Botrytis bunch rot and powdery mildew.
High-humidity conditions, paired with elevated nitrogen levels and cluster compactness, can promote a Botrytis outbreak. Grapes in condensed clusters can crack due to pressure, creating ideal entry points for fungus as well as a moist habitat for the spores to germinate.
Along with Botrytis, powdery mildew thrives in similar high-humidity and cool spring climates. The fungal infection settles on the surface of plant tissue and occupies the top layers of epidermis cells. Invasion of this disease can cause substantial damage to plant growth, crop yield and fruit quality.
The disease requires season-long maintenance because of early season inoculum and secondary infection caused by fungal spores that can infect, develop new spores and re-infect throughout summer months. Secondary infection cycles can occur approximately every five to 30 days, depending on the weather.
Careful and proactive control not only helps prevent these damaging diseases but also reduces the risk of epidemics later. UPL brings a portfolio of preventative and curative protection with products such as CUPROFIX® ULTRA 40 DISPERSS®, ELEVATE®, MANZATE® PRO-STICK™, MICROTHIOL® DISPERSS, PH-D® and PROCURE®, along with TOPSIN® M WSB for Eutypa dieback.
CUPROFIX ULTRA 40 DISPERSS Fungicide (FRAC Group M1) is a fixed copper sulfate option for control of powdery mildew and Phomopsis. Its unique DISPERSS formulation easily and completely mixes in the tank, allowing for more consistent and greater surface contact. For broad-spectrum control, CUPROFIX ULTRA DISPERSS can be conveniently tank-mixed with other labeled fungicides.
ELEVATE Fungicide (FRAC Group 17) provides locally systemic activity and is excellent at controllingBotrytis bunch rot and powdery mildew. ELEVATE can provide post-infection activity when applied early in the disease life cycle and has been shown to enhance the efficacy of other fungicides when used in a powdery mildew spray program. With a zero-day pre-harvest interval, you can use ELEVATE up to the day of harvest.
MANZATE PRO-STICK Fungicide (FRAC Group M3) provides advanced formulation technology in the fight against key diseases such as dead arm and downy mildew. A market-leading, multi-site, protectant fungicide, MANZATE PRO-STICK has effectively been used for decades without a reported incidence of resistance, making it a standard in almost any disease management program.
MICROTHIOL DISPERSS Fungicide (FRAC Group M2) combines sulfur and science to deliver excellent efficacy in a superior formulation for powdery mildew. MICROTHIOL DISPERSS also provides the added benefit of mite control. A patented micronized formulation process ensures a more consistent spray coverage and greater surface contact than other sulfur products.
PH-D Fungicide (FRAC Group 19) is a broad-spectrum fungicide that offers a high degree of powdery mildew and Botrytis control in grapes. Its benefit of a zero-day pre-harvest interval and 4-hour REI makes it an excellent option for disease management sprays close to harvest. PH-D is the only product in FRAC Group 19, making it an important resistance management tool.
PROCURE Fungicide (FRAC Group 3) is rated as one of the highest for powdery mildew control. PROCURE has both protective and curative efficacies in controlling diseases, as well as systemic activity in the plant. When applied in a powdery mildew spray schedule, PROCURE will enhance the activity of registered fungicides used for Botrytisbunch rot control. It’s also available under brand name TRIONIC Fungicide in a larger pack size.
If Eutypa dieback is your disease concern, TOPSIN M WSB (FRAC Group 1) is your go-to brand. TOPSIN is a systemic fungicide that moves from top to bottom, and upward and outward within the leaves and stem. It is recommended to rotate TOPSIN with fungicides in different FRAC groups. Use of TOPSIN M WSB for Eutypa dieback is approved for use under specific state local need labels.
Careful and proactive control not only helps prevent these damaging diseases but also reduces the risk of epidemics later. For more information on how to keep your vineyard disease-free this season, contact your local UPL sales representative or visit upl-ltd.com/us.
