DiseasesLeaf spot disease is a plant disease of alfalfa caused by fungi. Different types can be distinguished: Flap scab, leaf blight, downy mildew, crown rust, etc. Usually, leaf spot disease does not cause serious economic losses, but it can lead to reduced growth and leaf loss. Most likely to occur in warm, humid weather conditions. In case of severe damage, harvesting the plants is the best solution. However, the quality could be reduced as a result.
Flap scab Leaf blight Downy mildew
Wilt diseases are caused by pathogens (bacteria or fungi) that invade the vascular system of plants in warm seasons. This causes the plants to wilt and usually die. There are several wilt diseases:
Bacterial Wilt(Clavibacter ssp. The tip of the stalk withers. The leaves turn yellow. This disease can be avoided by using a longer crop rotation and choosing the right variety (USA varieties are resistant but carry the disease with them on the farm). Verticillium wilt – Symptoms begin as temporary wilting of upper leaves on warm days. Occurs in older populations. Can lead to yield reductions of up to 50%. Since Verticilium is evaluated for varieties on the French recommended list, resistant varieties (Bardine, Alexis) can be chosen.
Crown and stem rot
Anthracnose– This fungal disease begins with lesions on the stem, after which the upper part of the stem dies off. Since this can happen quite suddenly, the dead leaves remain attached to the stem. Anthracnose occurs most often in older stands under hot. Wet conditions in late summer on. The use of resistant varieties such as Artemis or Alexis is the only way to control anthracnose. Sclerotinia – Caused by the Sclerotinia fungus, this disease usually occurs under cool, moist conditions, usually in young stands. It can be recognized by a white fungal mycelium on the crown and stems and hard, black necroses. There is no genetic resistance, so Sclerotinia should be controlled by proper management. Removing all leaves before winter and strict weed control are necessary to ensure that air and sunlight can reach the base of the plants. This reduces the likelihood of fungal growth. Rhizoctonia– A very common fungal disease in arable crops such as sugar beet. Infected plants are stunted and the upper part of the roots are black and rotten. On alfalfa, it can occur after frost damage, poor drainage, heavy grazing, or when soil fertility is low.
Anthracnose Sclerotinia Rhizoctonia
Barenbrug offers different varieties of alfalfa depending on climate zone. Each variety has its own characteristics, suitable for different conditions.