Study on uptake and translocation of five fungicides in rice

Foliage spray is the most commonly used method of chemical pesticide application at present, but it has some defects such as evaporation, drift, bounce, rupture, and excess spread, resulting in low utilization of pesticides. Through the investigation of pesticide absorption and conductivity and the selection of appropriate pesticides for root application, the adverse effects of environmental factors on the active pesticide ingredients will be reduced. Longer efficacy can be maintained through slow release and dose regulation of pesticides to effectively improve the utilization of pesticides. In this paper, the absorption and conduction behaviors of five different types of fungicides (tricyclazole, thifluzamide, hexaconazole, epoxiconazole, azoxystrobin) in rice seedlings were studied through indoor nutrient soil and nutrient solution cultivation modes. The results showed that all the five fungicides could be absorbed and transmitted upward in rice seedlings, but the transmission performance was affected by the nature of the pesticides themselves. Under both cultivation conditions of nutrient soil and solution, the dose distribution of tricyclazole in the roots of rice seedlings was significantly higher than that in the aerial portions within 4 h-2 d, and the translocation factor (TF) values of tricyclazole in rice were all greater than 1 after treatment 5 days. It was shown that tricyclazole had the best upward transmission performance, while the other four pesticides showed poor upward transmission ability in rice. Tricyclazole is the most suitable for root application and the easiest to be absorbed by the root of rice and upward transmitted to leaves for the resistance to pathogen infections. This study can provide technical guidance for the pesticide selection of root application and the theoretical basis for the scientific and rational use of pesticides.