Broomrape on sunflower: how to protect your crop

Broomrape (sunflower broomrape, Orobanche cumana) is a parasitic plant without chlorophyll that attaches to sunflower roots and feeds on their sap. Infected plants are stunted and form small heads, and with heavy infestation yield losses can be very significant.

Why broomrape is so dangerous

A single broomrape plant produces tens of thousands of tiny seeds that remain viable in the soil for many years. The parasite constantly forms new races, so hybrids resistant to older races may become infected over time. Broomrape spends most of its development underground — by the time its flower stalks appear above the surface, the damage is already done.

Genetic protection is the foundation

The most reliable tool is hybrids resistant to the broomrape races common in your region. When choosing a hybrid, check which races it is declared resistant to and compare this with data on field infestation.

Clearfield and Clearfield Plus technology

Hybrids tolerant to herbicides based on imazamoxallow crops to be sprayed, which suppresses broomrape at early underground stages and also controls grass and broadleaf weeds. Spray at the stage indicated on the product label, usually at 2–8 crop leaves. Imazamox has soil residual activity — consider the restrictions for following crops in the rotation.

Agronomic measures

• Return sunflower to the same field no sooner than after 6–7 years.
• Destroy volunteer sunflower and host weeds.
• Clean machinery after working in infested fields — broomrape seed is easily carried with soil.
• Keep records of field infestation — this will help you choose the right hybrid and technology.

What to choose for your field

The best result comes from a combination: a resistant hybrid + herbicide technology + crop rotation. Our agronomist will help you choose a hybrid and herbicide program for your region and infestation level.

Full sunflower protection program →