Castor seed prices rose by Rs 15 to Rs 4,389 per quintal in futures trading due to acceleration in demand amid tight supplies from growing belts. 
At the National Commodity and Derivatives Exchange, castor seed for delivery in July gained Rs 15, or 0.34 per cent, to Rs 4,389 per quintal, clocking an open interest of 7,560 lots.
Castor seed for delivery in August edged up by Rs 12, or 0.27 per cent, to Rs 4,444 per quintal, showing an open interest of 82,170 lots.