pi_*-kernels of Lie groups

We study the group of homotopy classes of self maps of compact Lie groups which induce the trivial homomorphism on homotopy groups. We completely determine the groups for SU(3) and Sp(2). We investigate these groups for simple Lie groups in the cases when Lie groups are p-regular or quasi p-regular. We apply our results to the groups of self homotopy equivalences.