Hi Pamela,
Your "bamboo" are actually Dracaena cuttings that are rooting in water. Although they can survive in plain water for a long time, it is not unusual for the stems and roots to rot at some point. Yellowing of stems is a clear indication of that plant tissue having already died. The odor may be from the decomposing nitrogen from the plant tissue.
You can try removing all of the dead (discolored) stem tissue and re-rooting those stems in water or damp soil.
Good luck!
