Punjab Chief Minister Captain Amarinder Singh on Wednesday promised a thorough probe into the sale and supply of spurious pesticides and herbicides to farmers, warning of strict action against those found guilty.Responding to the issue raised by Akali MLA Bikram Singh Majithia, the Chief Minister vowed to get to the bottom of such cases, in which the farmers were being fleeced by unscrupulous dealers selling pesticides and insecticides.Captain Amarinder Singh pointed out such instances of sub-standard pesticides had been in existence for the past 40-50 years due to which the crop disease of Gulli-Danda had not been eliminated, causing extensive damage to the crops.He promised to take stern action against erring dealers and suppliers found engaged in sale of sub-standard/spurious pesticides.