Drought reduces the breakdown of plant residues. This means that inoculum of some diseases does not decrease as quickly as expected, and will carry over for more than one growing season. The expected benefits of crop rotation may not occur. Bacterial numbers decline in dry soil.

Some bacteria are important antagonists of soil-borne fungal diseases. These diseases can be more severe after drought. This information sheet looks at:

• how drought affects plant diseases
• crown rot
• rhizoctonia root rot
• inoculum
• yellow spot
• rusts
• wheat streak mosaic
• other cereal diseases
• burning stubble to control disease.