This paper presents studies performed for the monitoring of imidacloprid, clothianidin and thiamethoxam residues applied as seed treatment in rapeseed (Brassica napus ssp. oleifera), maize (Zea mays) and sunflower crops (Helianthus annuus). The experiments were located in representative areas of the mentioned crops. Residue levels were determined in plant samples at different phenological development stages, including flowers, as well as in bees and hive products (pollen, honeycomb, honey) by liquid chromatography/tandem mass spectroscopy (LC-MS/MS). The analyses were performed in ISO 17025-accredited laboratories, referring to the limit of quantification (LOQ), characteristic of the method used to determine the residues. In 2019, the percentage of samples that contained residues of the three substances, applied to the seed, was 16.39%, representing 20 samples out of the total of 122 analyzed samples. In 2020, 10 samples contained neonicotinoid residues above the LOQ, including 5 soil samples and 5 plant samples, representing 6.17% of the total samples. In 2021, from 149 samples with neonicotinoid applied as seed treatment, residues were identified in 12 soil samples and 11 plant samples, representing 15.43% of the total number of samples. In 2022, only 12 soil samples and 1 pasture sample contained residues above the LOQ. The results show that the highest percentage of samples with residues above the LOQ was recorded by the soil samples, while the flower and bee samples had the lowest percentages of samples with residues above the LOQ; no residues of the three neonicotinoid substances were identified in the honey samples.

This paper presents a three-year study concerning the effectiveness of the OSR seed treatment with the cyantraniliprole active ingredient in controlling the DBM larvae attack in autumn and four-year monitoring of the DBM flight pattern, using pheromone sticky traps. The experiment and the monitoring were conducted at the experimental field from the National Agricultural Research and Development Institute (NARDI) Fundulea in Southeast Romania. For the field assessments, each OSR sampled plant was photographed in macro mode, and then images were downloaded and magnified on the PC screen to determine the DBM larva attack. The traps were placed in the OSR crop from mid-March till December and checked twice weekly. Data from the field assessment revealed a higher pest attack on OSR plants on 11 November 2020, when the DBM larvae attack degree was 16.26% in the untreated variant and 11.24% in the variant with treated seeds. The results evidenced unusually higher activity for the diamondback moths during November 2019, 2020, and 2022; the beginning of December 2020 and 2021; and mid-December 2022. This is the first report from the Romanian scientific literature concerning higher DBM attacks at OSR plants in autumn and high moth activity during November and December.

Introduction: Rhizoctonia solani causes major damage to potato crops