Broad disease constraint resources are outlined in the Agronomists Toolkit. Specific disease categories are listed below:

Stem nematode

Constraint - Stem nematode

Description

Stem nematodes are relatively common plant parasites and are widespread in temperate areas of Australia
Stem nematodes prefer heavier soil types and cooler, moist conditions
Stem nematodes can tolerate desiccation

Symptoms

Distorted extra tillers or stems
Stunted growth and a very compact crown, giving a swollen appearance
Reduced leaf area either side of the midrib
Some symptoms may be confused with herbicide damage, water-logging or nutrient deficiency

Damage

Yield penalty is generally mild, though severe untreated infections can cause poor emergence and result in seedling death

Management

Controlling stem nematodes is difficult once they have invaded plants, so control efforts should focus on rotations involving non-host crops, controlling volunteer hosts in paddocks, and avoiding the spread of infested plant material, hay, seed and soil. Crop rotation remains the most effective means of control.