Question
I have a necterine tree that has some kind of small pin holes,or worm holes,an a jelly like
stuff on the tree,also the fruit an leaves have
a powdery dark grey powder on them,what is this an can I cure my tree?
thanks  

Answer
The pin holes are the entry holes of a borer (insect). I would spray the area with an insecticide--Dursban or check with your local garden type store for an insecticide for borers. The powder is more than likely powdery mildew.
This will take a fungicide spray to control this mildew. Also check your garden store for a fungicide to control powdery mildew. Good luck!