At the National Commodity and Derivatives Exchange, castorseed prices for delivery in September plunged Rs 91, or 2.19 per cent, to Rs 4,061 per quintal, in an open interest of 2,600 lots.
Similarly, the most-active June contracts also fell by Rs 42, or 1.09 per cent, to Rs 3,821 per quintal, with an open interest of 1,60,220 lots.
Marketmen said besides rising inventories, slackness in demand from paint and soap industries in physical markets led the fall in prices at futures trade.