LADYBIRD LARVA EATING APHIDS ON ROSEBUD WITH RED KNOBS ON

It's a funny thing but yesterday I noticed that, on a plant, in a pot, at the front of my home, there was a little ladybird larva.  The plant's leaves are light grey and there wasn't an aphid in sight.  Ladybirds (or Ladybugs) and their larva eat aphids so what was the larva going to do.  I tore off the leaf and took it, and the larva, to my back garden where lunch was served in plenty on my climbing roses, New Dawn and Wild Eve.  I wedged the leaf into place, near aphids, and left the ladybird larva to decide what to do.  An hour later I checked and there it was, on a rosebud, eating its fill of aphids.  I took a macro photo, shared here. 

Ladybird larva on rosebud, eating aphids, but what are the red things?

Ladybirds are good, so look after them.  Best not go spraying pesticides around and killing off the gardener's little helpers. 

Ladybird in my garden - a gardener's friend

It was only when processing the image, from camera to computer, that I noticed the little red knobs on clear stalks jutting out of the rosebud.  In all the years that I have grown roses, I have never seen, or noticed, that before.  Checking the internet, it's nothing uncommon but I could find no information whatsoever telling me what they are, what purpose they serve.  They seem a very natural part of the rose but not all the rosebuds have them.  If I ever discover the answer, I shall add it here. 

It's nice to know that I have parasite eating predators in my garden.  Makes a lovely change from plant destroying snails, aphids, and vine weevils.

It's not just the gardener who has problem with pests, even bugs are bugged.  For example, the poor hoverfly and bees, both helpful insects, have their own burdens in the form of mites, and slugs do too.

Bumblebee infected with mites

Hoverfly infected with pathogenic fungus, Entomophthora muscae

Slug with parasites