[Nick36]

Hello my friend has a nectarine tree, which has whitefly.  They have passed something on to the tree, making it blister a red colour.  As this is an edible crop do i just spray with a safe insecticide?  If i get rid of the whitefly and remove the worst affected leaves should it improve?

[Yorkie]

I'm not a fruit expert but wasn't aware that whitefly attacked nectarines, nor that they left deposits that were rusty coloured.

I suspect that there is something else going on here - either it isn't actually whitefly, or something in addition to it.

Not sure what it is, will look at my books later on and come back if anything occurs to me.

Edit: could it be peach leaf curl?