Tips for preventing and managing dodder in alfalfa.
A parasitic plant, dodder, has impacted alfalfa production since the 1950s. Its capacity to proliferate very quickly and the long-lived nature of the seeds in the soil make it highly problematic for producers.
What is Dodder?
- Dodder is a non-chlorophyll-producing parasitic weed.
- Dodder’s filaments have suckers which directly tap into alfalfa’s nutrients.
- The filaments of dodder grow quickly to form clusters in the fields that form large circles in plots, which strangle the alfalfa.
- A lot of other plants are sensitive to dodder: clover, beetroot, tomato, carrot, potato, but also some weeds such as knotweed, nettle, Umbelliferae, feverfew...
There are two primary species of dodder that can interfere with alfalfa:
- Cuscuta Campestris Yunck « big cuscute »Orange filaments
- Cuscuta Epitymum L. « small cuscute ». Straw yellow filaments
The fight against dodder starts by choosing certified seeds to avoid contamination by seeds. In case of the appearance of a cluster, it is important to rapidly apply chemicals in the zone. Only the destruction of the host plant allows the eradication of dodder. As a precaution, application zones must overlap the cluster by 2 or 3 meters.
The fight against dodder starts by choosing certified seeds to avoid contamination by seeds.
MAS Seeds alfalfa seed is certified to have 0% dodder in the bags.
Biology of Dodder
- Seeds germinate at or just below the surface (0-10 mm).
- Big dodder germinate at optimal temperatures of 30°C. Small dodder germinate at optimal temperature of 15-20°C.
- Germination can occur without host plant => Lifetime 10 days.
- The filaments grow quickly and it spreads rapidly over a few meters.
- First flowers appear 4 to 6 weeks after germination.
- Thousands of seeds ripen quickly (2000-3000 seeds per stem).
Seed Longevity and Spread:
- Dodder seeds can exist in the soil for a long time.
- Under good conditions seeds can survive in the soil for up to 40 years
- Agricultural machinery and crop production favour the dissemination of seeds across fields
- Farm seeds is the first origin of dodder infestation.
- Stored seeds can be transported by water, animals, tillage or harvest machinery.
How to Fight Dodder?
Preventive way…avoid the introduction in field!
- Use tools cleaned for working the soil, and for the harvesting.
- Sow certified seed, guaranteed without dodder.
- In case of early infestation, the only ways to fight dodder is to destroy host plant.
- Burn with straw or use a specific weedkiller (ask advice to your technician) a few meter overflow the rounds.
- If dodder is spread through all the field, it is recommended to destroy the crop.
To get agronomic advice or find seed, contact find your local MAS Seeds representative.