Method for testing toxicity of residual nicosulfuron on corn

Abstract

The invention discloses a method for testing the toxicity of residual nicosulfuron on corn. A group of nicosulfuron solutions, the concentrations of which are gradiently distributed, are sprayed in a group of tested soils, and corn seeds are sowed on the sprayed tested soils; on the first day after spraying, the in-situ pore water of all the soils is collected, and the nicosulfuron concentrationsin the in-situ pore waters are determined; after a plurality of days of culture, the plant heights of corn are determined; finally, a dose-effect curve equation for the plant heights and the nicosulfuron concentrations in the in-situ pore water and the nicosulfuron concentrations IC50 in the in-situ pore water at the corn plant height inhabitation rate of 50 percent are obtained by fitting; the nicosulfuron concentrations in the in-situ pore waters of the soils to be tested are determined, and according to the dose-effect curve equation, the plant height inhabitation rate of the soils plantedwith corn is predicted. The method is easy and rapid to operate, and can rapidly predict the phytotoxicity of nicosulfuron in soil to be tested according to the dose-effect curve equation of the nicosulfuron in the soil and the concentration of the in-situ pore water in the soil to be tested.

Description

Technical field [0001] The invention relates to the field of herbicide safety evaluation, in particular to a method for detecting the toxicity of residual nicosulfuron to corn. Background technique [0002] Nicosulfuron is a sulfonylurea herbicide developed jointly with DuPont from 1987 to 1988 by Ishihara Industrial Company of Japan. It was sold in the United States under the trade name Accent in 1991 and registered for use in sweet corn in 1996. Nicosulfuron has been in my country for more than ten years. Because of its low dosage and good effect, it is very popular. [0003] The agent is a systemic conductive sulfonylurea herbicide, which can be absorbed by plant stems, leaves and roots and quickly conducted in the xylem and phloem. By inhibiting the activity of acetolactate synthase, it hinders the synthesis of branched chain amino acids, thereby affecting plant cells Split, stop the growth of weeds and eventually die. The weeds will stop growing quickly after absorbing the d...

AI Technical Summary

Problems solved by technology

However, due to different soil physical and chemical properties (pH, organic matter content, etc.), herbicides in different soils have different bioavailability, and the traditional phytotoxicity indicators (EC50 or IC50) based on total concentration measurement and calculation are usually different due to different soil types. are different and not comparable to each other

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