Cyst Nematode
Heterodera glycines (soybean), H. schachtii (sugar beet), Globodera rostochiensis, G. pallida (potato)
Overview
Sedentary endoparasitic nematodes that form protective cysts (hardened female bodies) containing hundreds of eggs that can persist in soil for many years. Major pests of soybeans, potatoes, and sugar beets.
Symptoms
Stunted, yellowing plants in patches. Poor root development. Tiny lemon-shaped cysts visible on roots with magnification. Reduced yield. Plants may wilt under stress. Symptoms worsen over successive years of monoculture.
Environmental Conditions
Variable
Prevention
Rotate with non-host crops on a 3+ year cycle. Plant resistant varieties. Use certified nematode-free seed potatoes. Avoid moving infested soil. Clean equipment between fields.
Management
Long crop rotations (5+ years for potato cyst nematode). Plant resistant varieties. Trap crops that stimulate hatch but don't support reproduction. Biofumigation with brassica cover crops.