  The dynamics of open quantum systems and manipulation of quantum resources
are both of fundamental interest in quantum physics. Here, we investigate the
relation between quantum Markovianity and coherence, providing an effective way
for detecting non-Markovianity based on the \textit{quantum-incoherent relative
entropy of coherence} ($\mathcal{QI}$ REC). We theoretically show the relation
between completely positive (CP) divisibility and the monotonic behavior of the
$\mathcal{QI}$ REC. Also we implement an all-optical experiment to demonstrate
that the behavior of the $\mathcal{QI}$ REC is coincident with the entanglement
shared between the system and the ancilla for both Markovian and non-Markovian
evolution; while other coherence-based non-Markovian information carriers
violate monotonicity, even in Markovian processes. Moreover, we experimentally
observe that non-Markovianity enhances the ability of creating coherence on an
ancilla. This is the first experimental study of the relation between dynamical
behavior of the $\mathcal{QI}$ REC and the phenomenon of information backflow.
Moreover, our method for detecting non-Markovianity is applicable to general
quantum evolutions.
