Comparative hygienic assessment of pesticides behavior in soil in intensive grain farming technologies

Abstract

The aim: Was the comparative hygienic evaluation of the pesticide behavior in the soil after application on cereals. Material and methods: Methods of full-scale in-field hygienic experiment, high-performance liquid (HPLC), gas-liquid (GLC), thin-layer chromatography, statistical, bibliography were used in the research. Results: Data on the detailed conditions and land parcels treated with studied pesticide formulation and its a.i. are highlighted in the article. The actual levels of the different classes a.i. content in soil and its dynamics were determined, based on which the dissipation rate constants (K) were calculated, as well as quantitative parameters of stability (τ50, τ95, τ99). Conclusions: Azoxystrobin, benzovindiflupyr, epoxiconazole, propiconazole, prochloraz, cyproconazole can be classified as of low hazardous substances, and trinexapac-ethyl, kresoxim-methyl, picoxystrobin, and tebuconazole are considered to be moderately hazardous. Among all pesticides studied, tebuconazole is the longest persists in the soil; epoxiconazole and propiconazole are most likely to disappear from the soil. Calculated values of half-lives of the studied substances in the agro-climatic conditions of Ukraine are slightly different from the results of in-field experiments that were conducted in other countries, namely: azoxystrobin, epoxiconazole, propiconazole, and cyproconazole disappear from the soil more quickly; the kresoxim-methyl and pinoxaden disappear more slowly. Meanwhile, the persistence of benzovindiflupyr, picoxystrobin, prochloraz, trinexapac-ethyl, and tebuconazole does not differ from the persistence in soils of European countries.