The Italian news agency ANSA reported 200 protesters rallied Tuesday outside the agriculture ministry, waving banners that highlighted their concern about the relationship between the nicotine-based seed treatments and bee colony die-offs.

The National Union of Italian Beekeepers said some studies have suggested the insecticide leads bees to stop feeding larvae and hurts their navigational abilities. It is estimated about 200,000 beehives disappeared in Italy last year, ANSA said.

The agricultural union Coldiretti said a third of all farm produce depends on insect pollination, mostly carried out by bees.