Construction of a novel mathematical model for predicting pesticide release in soil and its application in rice pest control

It is important to control and predict the release of pesticide to improve the utilization rate of pesticide and reduce environmental pollution. Sodium lignosulfonate/UIO-66-NH2 was constructed by cross-linking method as the model carrier, and thiamethoxam was used as the model pesticide to study and establish the mathematical model of thiamethoxam release in the indoor and the actual soil. The results suggested that the indoor and soil release kinetics of carriers follow the Weibull and Higuchi model respectively. To address the cumbersome and time-consuming of soil detection, linking the indoor and soil release behavior of the carrier, a novel mathematical model was established based on release kinetics model to predict the release of carrier in soil. Mathematical model had good accuracy in the error analysis, and its predicted release time of the carriers in soil was 48.74 d, which the actual time is 45 d. In addition, carries showed good biocompatibility in zebrafish and microbial toxicity tests, and was effective in reducing Cnaphalocrocis medinalis infestation in field trials. At 72 days, the leaf-curl rate of rice treated with carrier was only 12%, while that of pure thiamethoxam group was 34.9% This work provides theoretical support for the efficiency use of pesticides, making it possible for mathematical models to guide agricultural production.