Effects of Triallate on Wild Oat Grown in a Growth Chamber

Triallate [S-(2,3,3-trichloroallyl)diisopropylthiocarbamate] mixed with soil (1.5 ppmw) stimulated coleoptile extension, reduced the length of the primary leaf, but had no effect on mesocotyl development of wild oat (Avena fatua L.) grown in soil in a growth chamber. Incubation of the triallate-treated soil for as long as 20 weeks at constant temperatures (10 C, 16 C, and 20 C) did not reduce phytotoxicity. Triallate phytotoxicity was similar at soil moisture levels of either 5% greater than wilting point or 5% less than field capacity. The phytotoxicity remained the same after a freezing cycle during an 8-week soil incubation. Phytotoxic effects of triallate were markedly reduced as soil organic matter increased.