Castor seed prices hardened by Rs 62 to Rs 3,900 per quintal in futures trading today.
Marketmen said speculators enlarging their positions influenced by firming trend in physical markets led to the price rise.
At the National Commodity and Derivatives Exchange, the April contract jumped up by Rs 62, or 1.62% to Rs 3,900 per quintal, clocking an open interest of 2,550 lots.
The February contract gained Rs 17, or 0.55% to Rs 3,743 per quintal, showing an open interest of 82,600 lots.
The January contract also moved up by Rs 16, or 0.44% to Rs 3,649 per quintal, having an open interest of 80,640 lots.
