The helpline has been very busy over the past couple of weeks as farmers have been making good progress with drilling and spraying, especially now that all areas, such as Lincolnshire, have at last received some much needed rainfall.
Typical questions being asked are :
- How long will Redigo Deter (prothioconazole + clothianidin) protect my cereal crops?
Redigo Deter will protect mid September drillings, from aphid attack, for 8 – 10 weeks and for late September drillings we would expect crops to be protected for more than 10 weeks.
- Is it OK to apply Liberator at peri-emergence?
In some drier parts of the country growers have been holding off from applying their autumn cereal residuals. Now that rain has arrived crops have started to emerge. Liberator is approved for application at pre, peri and post emergence for both winter wheat and winter barley. However it would be advisable not to apply multiple tank-mixes at peri or early post –emergence especially if frosts are forecast.
- 3) What is the threshold and what rate of Proline 275 (prothioconazole) should I apply to protect my crop from both light leaf spot and Phoma?
- The recent rainfall has increased the risk of Phoma infections in oilseed rape. For late sown crops the threshold is 10 % plants showing lesions and 20 % for well established crops. Where growers are planning to apply a split dose the application rate is 0.32 L/ha. Where it is not possible to apply a split dose we would recommended a higher rate of 0.46 L/ha.
- The second Phoma application would normally coincide with the timing for a light leaf spot timing (November) and a split Phoma programme should protect against light leaf spot as well.
- 4) Conditions have favoured early emergence of black-grass this year.
- Atlantis can be applied from the 1 leaf stage of black-grass when the majority have emerged, and when the crop has reached the 2 leaf stage.