Yellow Rust!

Over the last 10 days I have come across a worryingly uncommon (for the very southwest) level of yellow rust in wheats and triticale, from way down by St Austell and Truro in Cornwall, to the Tamar Valley around Launceston, around Okehampton and now up around Holsworthy and Bradworthy in North Devon. It is also present in four varieties as of last week at the official Nickerson wheat trial site at Silverton, near Exeter. This last site, being closest to the midlands was not entirely surprising given the climate and locality.

Last week, four varieties were displaying symptoms. Another variety in a separate trial was also showing symptoms. Not entirely surprising given their rust ratings.

What I wasn't quite expecting to see was the level of infestation in my trial at Tregony way down in Cornwall. More worryingly was the level of disease in fields in the locality, some fields being yellow across the whole field. I have taken some samples to be analysed to see which strains are involved.

Leaf 2 of plants near Okehampton, disease just getting going.

More advanced infection near Tregony.

Another shot near Tregony.

The difference between a resust susceptable variety and a resistant one.

Classic focii of an outbreak of Yellow Rust. Near Launceston, Cornwall.

Major damage, this is Winter Triticale near Holsworthy. It only takes a short while to go from initial outbreak to this, that is why controlling the disease is so vital! What is more disturbing is the fact that most triticale varieties are being grown with supposedly good resistance to yellow rust, especially on organic farms. So to see this in a conventional farm is not good.