Key Points
- Gaucho controlled cereal aphids up until the start of tillering (GS21).
- The variable length of emergence time from three sowing dates did not affect the persistence of Gaucho. For all three sowing dates persistence broke down at, or just before, the start of tillering (GS21).
- After ingestion of Gaucho, aphids will stop feeding but may take up to 7 days to die, especially in cooler weather.
- Results suggest that the volume of plant growth is a major factor in Gaucho persistence.
- Wheat sown before mid-May will require a follow-up foliar aphicide at the start of tillering (GS21).