Brussel Sprout Ploblem

[littlemoney]

I've been asked this question by a friend and I don't know the answer.

He went to transplant brussels and notice inner leaves down the centre are purple in colour. Closer examination shows what could be very small eggs or a greyish colour fungus growing on to of leaves causing then to curl in, out leaves are fine.

The plant looks healthy from the outside and show no sign of dying.

I am aware that downy mildew is a greyish powder but nothing about leaves going purple. He has remove greyish mater and transplanted them

Does anyone have any suggestions as to what this is please and if any treatment is needed. Thanks

[ameno]

Sounds like mealy or woolly cabbage aphid. They are dark grey to black aphids covered in a pale grey powdery or woolly substance. Aphid feeding can often cause the leaves to distort or to change colour, as well. It's caused by certain chemicals the aphid inject as they feed.
Tell him to try to rub off as much as he can, but otherwise they should probably be fine.

If it were downy mildew the leaves would be soft and limp. The actual downy stage is the final (sporing) stage of the fungus, so by the time the down becomes visible it has already fed heavily on the leaf and the effects of that will be quite noticeable. If an otherwise healthy, perky leaf is "downy" then it's almost always something else, not fungus.

[littlemoney]

ameno Thanks for your advice. I have passed the information on