Seed treatments for spring crops

Good crops start with good seed and with more spring crop likely next year it could pay to get orders for spring barley seed in early.

At the same time as making variety selections and ordering seed, it is sensible to think about preferred seed treatments rather than opting for something that isn’t tailored to your needs.  The days of seed treatments that worked against the whole spectrum of barley seed-borne diseases are sadly behind us and, while most treatments cover off seedling blight risk, there are now choices to made if you need net blotch or loose smut control as there are no treatments which cover both.   And if you plan to use home saved seed then testing for germination is the bare minimum but checking for seed-borne diseases like loose smut, leaf stripe and net blotch is also important both in selecting low-risk lots but also to choose the most appropriate treatment.

Spring barley is at lower risk of losses to seedling blight if it goes in to warming soils and gets away fast.  Going without a seed treatment if the seed has been tested and found to be free of seed-borne diseases and you are confident it will go into later slots and warmer soils is always an option. It might be prudent to treat some if you will be drilling a portion early when we could still get a few false starts to spring and cold/wet conditions can still follow early drillings. If you intend keeping the crop for seed then it would be best to treat as seed-borne disease will build rapidly from a couple of easily missed heads in one season to significant infestation the next.

We had a run of seasons with more loose smut in spring barley which was sometimes linked to the use of cut-rate seed treatments.  There was a bit less loose smut about in 2018 and 2019 but with unconfirmed reports of reduced sensitivity to azole fungicides in loose smut, it is prudent not to go cutting rates again and to use the seed treatments which claim good efficacy.  Loose smut is carried deep within the seed so can be harder to manage than other diseases like Microdochium carried on the surface.  Seed treatment options for loose smut include Redigo Pro and Rancona.  For seed where net blotch is detected though you would want to choose a treatment with good efficacy against that disease such as Anchor or Beret Gold.

Fiona Burnett SRUC, for the Farm Advisory Service.