Rationing may lead to increased demand for other commodities that can be purchased freely while Hoarding is an increase in demand. In the short-run with supply fixed, the price of the hoarded good would increase.
Rationing refers to an artificial control on the distribution of scarce resources, food items, industrial production, etc. In banking, credit rationing is a situation when banks limit the supply of loans to consumers. In economics, rationing refers to an artificial control of the supply and demand of commodities.