1. Optimizing healthy plants includes strategies such as:
(select all that apply)

A. Using resistant varieties
B. Planting susceptible crops to increase disease tolerance
C. Rotating crops
D. Reducing crop stress
SHOW ANSWER Answer: A, C and D — Be aware of disease issues in previous years and avoid planting susceptible crops in high risk areas.

---

2. Sources of disease include:
(select all that apply)

A. Stressed crops
B. Crop stubble
C. Soil
D. Weeds
SHOW ANSWER Answer: B, C and D — Disease pathogens can persist in crop stubble, in certain weeds, and in soil. Stressed crops are more susceptible to disease but are not in themselves a source of disease.