Does the row locking on slave database also apply to master database?
There is no communication from Slave to Master (aside from network protocols to receive the Replication updates from the Master.

Writing on a Slave is a no-no.  The basic principle of Replication is that the Slave will have exactly (except for a slight lag) the same data as the Master.  Writing to the Slave does not allow for keeping them in sync.

An exception is with Master-Master -- wherein two servers are acting both as Master and as Slave.  Still, writing to both leads to a lot of potential problems, and should be avoided.