This is very much a page-under-development. Can
DM be passed on through the seeds at all? The RHS has found DM DNA in
seed samples from infected seedpods. This could be fungal-tissue
contamination from infected pods, including spores, on the seed-cases.
If there are oospores present, there is a theoretical risk of them
infecting the emerging seedlings.
Or, a worst-case scenario, it could be infection within the seed itself, in which case the seedlings could grow already systemically infected with DM.
YOUR HELP IS NEEDED. I will be sowing such potentially-infected seeds, and so will the RHS and an experimental station in Germany. (May 2022 update... no infected seedlings found in my batch). Please also send in information, especially photos of any infected seedlings you have grown. I will need this information: source of seeds and (where possible) name (or at least description) of mother plant. Do you already have DM in the garden? How and where did you sow the seeds? (Outdoors, indoors, self-sown, new compost, when sown etc etc) What were the initial symptoms, and the current ones? This is all information that will help to paint a picture of whether any infection arose 1) from outside sources: contaminated soil, or blown-in spores 2) from spores on the seed itself 3) from infection within the seed. So, please any information will be very useful. Thank you.
Aquilegia Downy Mildewed Seedlings
|I THINK that it IS possible to get systemically infected
seedlings UPON GERMINATION
I have seen some tiny seedlings that look quite white (creamy white) and very different to white-flowered aquilegias that have a lighter whiter green leaf with no purple in the leaf stem up to normal seedlings.
|Sorry no pics, only seen this a couple of times and getting a camera wasn't my priority!|
|When I have seen such suspect seedlings I have scooped out that seedling together with an amout of the compost around it (that may have become infected if spores are released) and put it in with rubbish collection. And kept a close eye on the rest of the seedlings of that batch. So far, so good.|
|Look out for browny spots and shrivelling of petals.|