if new growth is yellow i'd guyess too much P.
more than one thing causes tip burn. P will also have chlorosis on new growth.
spots, interveinal chlorosis and burnt tips would be k-def.
burnt tips alone maybe S-tox.
Gotta cross-reference all the symptoms to make an educated guess.
thought you were talking about the tip of the leaf... those are female organs. if it has hair-like projections it's female.
male bits will be at end of a twig too, where as female bits will not.