|Drilled August/early September and/or drilled at lower seed rates||Use of Redigo Deter before the end of the first week in September and/or at seed rates lower than 100 kg/ha may result in reduced BYDV control. However, the use of Redigo Deter in these situations is likely to provide the basis for a programmed approach to successful BYDV control that will need one (rarely two) subsequent spray.|
|Drilled middle 2 weeks in September||Considerably increased BYDV risk and need for follow up sprays.
Use a minimum of 100 kg seed/ha followed by a well-timed aphicide spray.
Here Redigo Deter provides the vital initial BYDV protection at a very busy time of year, before monitoring of aphid activity needs to begin.
|Drilled late September or after||A minimum seed rate of 125 kg/ha will normally provide equivalent protection to two well-timed aphicide sprays.|
NB: With earlier drillings, in seasons and/or localities where aphid fly-in extends beyond the first week of November, an additional spray is likely to be required.
Reduced seed rates for winter cereals
The recent trend towards earlier drilling of reduced seed rates for winter cereals (especially wheat) can have a marked impact on the performance of Redigo Deter seed treatment.
Earlier drilling increases the exposure to intense aphid fly-ins during early autumn, with a greater attendant risk of BYDV infection.
Using lower than conventional seed rates, especially with seed of high thousand grain weight, results in fewer established plants per square metre. These more widely spaced plants grow and tiller more vigorously than conventional drillings, which leads to a faster dilution of clothianidin within the plants, reducing the period of protection afforded by Redigo Deter against BYDV. In addition, as crop populations decrease, individual plants suffer higher aphid levels, and BYDV infection pressure increases.
Nevertheless, in comparison to a pyrethroid spray, Redigo Deter products give superior aphid control on both 100 and 150 kg/ha plots.