Akademik Veri Yönetim Sistemi
5th Agriculture, Environment and Health Congress, Aydın, Türkiye, 17 Şubat 2022, ss.130
The aim of this study was to monitor the degradation
of some insecticides (chlorpyrifos-ethyl, deltamethrin and imidacloprid) and
their metabolites [3,5,6-trichloro-2-pyridinol (TCP), diethyl phosphate (DP),
diethyl thiophosphate (DTP), chlorpyrifos-oxon (CO), 3-phenoxybenzoic acid
(3PBA), 3-(4-hydroxyphenoxy) benzoic acid (4HPBA), imidacloprid-olefin (IMO),
imidacloprid guanidine (IMG), 6-hydroxynicotinic acid (6HNA), and
6-chloronicotinic acid (6CNA)] during the 200-day fermentation period of silage
samples. The research question of this study is that the maize fermentation
processes could affect the degradation of applied insecticides and their
metabolites. Because, lactic acid bacteria (LAB) convert water-soluble
carbohydrates into different organic acids, resulting in a pH drop to protect
the forage against harmful bacteria during the ensiling process. Thus, acidic
conditions occurred in maize silage and insecticides are metabolized by microorganisms
present in the fermentation environment. In current study, these insecticides
were applied separately to maize plants grown in a controlled manner without
using pesticides under laboratory conditions. Some of the spiked maize plants
were left to dry and the other part was made silage in jars and kept in
laboratory conditions. In order to determine the effect of fermentation, the
insecticides and their metabolites applied in both dried and silage samples
were analysed periodically using LC–MSMS. Organic acid, microbiology and pH analyses
were performed on silage samples in each sampling period in order to determine
the maturation status of the silages. In silage samples, the degradation of chlorpyrifos-ethyl,
deltamethrin and imidacloprid was less with rates of 46, 45 and 30%,
respectively, compared with the control samples (67, 55 and 61%,) 200 days
after the insecticide application. The present study showed that the presence
of LAB in the maize fermentation accelerated pH decline, and these conditions
probably decelerated the degradation of these insecticides.