Electrically charged insects/plants - (Feb/03/2015 )

“Plants are usually charged negatively and emit weak electric fields. On their side, bees acquire a positive charge as they fly through the air. No spark is produced as a charged bee approaches a charged flower, but a small electric force builds up that can potentially convey information. The flower's potential changes and remains so for several minutes".
(Link: http://www.sciencedaily.com/releases/2013/02/130221143900.htm)
 
My question is: does this account for all plants/trees? And what about other (non flying) insects than bees? And from where does this plant emit its electric field?
 
Are there more examples of this electrical attraction between (sea) plants and pollinators?

Link fixed... Bob.

For the first question you've to ask a plant physiologist. I think an emitter is not necessary since the plant surface is charged as it is, i.e. there's an excess of electrons (negative charge).

Flying insects seem to be more or less all charged by "...frequently colliding with microscopic mid-air particles like dust and small molecules. These strip electrons from their cuticles—their outer shells—leaving them with a positive electric charge." (got it from a webpage)

So it surely depends on how often, how long and fast they fly and how large they are, i.e. small weak fliers (e.g. aphids, midges) fly usually at low speed, small distances and not so frequently. So the chance and time to be charged is quite low. With larger and good fliers (e.g. bees, larger flies) it's the opposite, they fly fast, fly larger distances at considerable speed and do this often enough to gain higher charges.

Insects that do not fly won't be charged because of the missing chance to be charged and the continuous charge equalisation on the ground.

Since the mentioned publication (btw your link is dead) is the first one reporting this and it's from 2013 (I think), I doubt there will be many other sources about this issue (but check the literature in the publication).