Castorseed futures for May dropped by Rs 43, or 1.1%, to Rs 3,867 per quintal in 100 lots.
At National Commodity and Derivatives Exchange, the January contract declined by Rs 26, or 0.72%, to Rs 3,610 per quintal in 1,640 lots.
Selling by traders alongside weak spot markets affected the trade.
Fall in export demand put pressure on castorseed futures trade.
Lower off-take by industries too dampened the trading sentiments.
The February contract fell by Rs 26, or 0.71% at Rs 3,658 per quintal in 1,27,870 lots.