Responses of Several Corn (Zea mays) Cultivars and Weed Species to EPTC With and Without the Antidote R-25788

Abstract

Field experiments were conducted to determine the effectiveness of the herbicide antidote R-25788 (N,N-diallyl-2,2-dichloroacetamide) in protecting corn (Zea maysL.) cultivars from EPTC (S-ethyl dipropylthiocarbamate) injury. Preplant-incorporated applications of EPTC, with and without R-25788, were made to a fine sandy loam in 1976 and a loamy sand soil in 1977. EPTC at 6.7 kg/ha was 20 to 30% more injurious to the susceptible cultivars grown in sandy, lower organic-matter soil than in fine sandy loam. R-25788 did not decrease the weed-control efficacy of EPTC. The cultivar ‘TXS114’ was highly tolerant to EPTC at 6.7 kg/ha with or without antidote protection. Most of the other EPTC-susceptible cultivars showed significant stand improvement when R-25788 was used in combination with EPTC. R-25788 did not alleviate EPTC phytotoxicity toward ‘XL55’ and ‘XL379’ cultivars. EPTC applied in combination with R-25788 showed no, or only, slight injury to all other cultivars.