Comparative Effects of Three EPTC Antidotes

Abstract

In growth room studies,N,N-diallyl-2,2-dichloroacetamide (hereafter referred to as R-25788) was the most effective of three antidotes for the reduction of EPTC (S-ethyl dipropylthiocarbamate) injury to corn (Zea maysL. ‘United Hybrid 106’). R-25788 reduced EPTC injury to corn as a seed treatment, as an incorporated soil spray, or in nutrient solution in quartz sand nutrient culture. CDAA (N,N-diallyl-2-chloroacetamide) was also an EPTC antidote for corn when applied to the soil or in nutrient solution but was itself toxic to corn when applied as a seed treatment. The antidote 1,8-naphthalic anhydride (hereafter referred to as naphthalic anhydride) was less effective than R-25788 as a seed treatment and was ineffective when applied to the soil. Naphthalic anhydride was the only one of the three antidotes which also reduced EPTC toxicity to green foxtail [Setaria viridis(L.) Beauv.].