The minimum concentrations of organic solvents inducing phytotoxicity were investigated after spraying or flooding solvent solutions to annual plants.
In the foliar treatment of upland test, solvents with high-boiling point or low-polarity induced severe phytotoxicity. Especially, aromatic solvents induced severe phytotoxicity. The most sensitive plant to phytotoxicity was soybean.
In the pre-emergence treatment of upland test, the solvents with high-boiling point only induced phytotoxicity at high concentration.
The degree of phytotoxicity induced by foliar spray in the condition of paddy field was similiar to that of upland test, but in the pre-emergence test, the former was more severe than the latter. Among 6 treatments, phytotoxicity induced by solvents was most severe in the pre-emergence test under the condition of flooding paddy field. Generally, alcohols induced severe phytotoxicity, especially, ethanol at 0.001%.
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