Karma and Contact with Dharma I'm wondering whether the knowledge of the Buddhist path and participating in it would be the fruition of good karma? I mean, since following this path implies virtue and further good karma, even if done temporarily, I would assume good karma is necessary to attain it. 

I also wonder whether the adherence to the path -- e.g. stream entry, Bodhisattva bhumis -- occur as well from the accumulation of karma. In other words, does accumulating a certain level of good karma promote or even ensure that rebirths will generate good karma as well?

Thank you
I'm wondering whether the knowledge of the Buddhist path and participating in it would be the fruition of good karma.

First of all, it takes a lot of good Karma to attain human life, it is through human life only that one can work on oneself to attain Nibbana. Human life is a rare occurring. Then, of course, it takes a huge amount of intelligence, maturity and millions of lives of good karma to arrive at the true Dhamma and to arrive at the understanding that, 'desire is the root cause of sorrow'.

In other words, does accumulating a certain level of good karma promote or even ensure that rebirths will generate good karma as well?

This is something circumstantial. You might be reborn in brahma realm and you might do bad karma and then reborn in lower realms. There is no guarantee of rebirths generating good karma.