Castorseed prices gained 4 per cent on concern over monsoon as rain deficit looms large in most parts of the country .
Moreover, industrial demand supported the price uptrend in the oil.
On the National Commodity and Derivatives Exchange (NCDEX), castor August contracts increased Rs 170 to Rs 4,397 a quintal with an open interest of 14,730 lots.
September series moved up by Rs 177 to Rs 4,583 with an open interest of 99,500 lots. September contract on Rajkot Commodity Exchange gained Rs 100 to end at Rs 4,426 for 100 kg. RCX spot castor rose Rs 25 to Rs 3,832.50 a quintal.
About 70,000-75,000 bags of castor arrived in Gujarat and quoted at Rs 750-765 for 20 kg. About 7,400-7,500 bags arrived in Saurashtra and quoted Rs 740-770 for 20 kg.