Guar seed prices on Tuesday declined Rs 36 to Rs 5,752 per quintal in the futures trade amid an increase in supply from producing regions. On the National Commodity and Derivatives Exchange, guar seed contracts for October delivery fell Rs 36 or 0.63 per cent to Rs 5,752 per quintal with an open interest of 36,640 lots. Marketmen attributed the downward trend in guar seed prices to increasing supplies from growing regions.