Evaluation of the sublethal effect of tetrachlorantraniliprole on Spodoptera exigua and its potential toxicity to two non-target organisms

Tetrachlorantraniliprole (TCAP) is a novel anthranilic diamide insecticide that specifically targets the ryanodine receptors of lepidopteran insect species with excellent insecticidal activity. Previous studies have reported the sublethal effects of multiple diamides on several lepidopteran species, whereas the sublethal and non-target effects of TCAP remain largely unknown. We assessed the sublethal effects of TCAP on Spodoptera exigua. We also investigated the effects of TCAP on non-target Harmonia axyridis and Eisenia fetida, S. exigua was more sensitive to TCAP than to chlorantraniliprole, as the LC50 (10.371 μg L-1 at 72 h) of TCAP was relatively lower. Compared with those of the control, sublethal concentrations of TCAP (LC10 and LC30) not only prolonged the duration of the larval and pupal stages as well as the mean generation time but also reduced certain population parameters. On the other hand, TCAP exposure, even at the highest concentration, did not induce toxic effects in H. axyridis ladybugs (1st instar larvae and adults) or E. fetida earthworms. Taken together, our results suggest that TCAP can be used as a novel and promising component of the integrated pest management (IPM) program against S. exigua due to its robust target effects and negligible non-target risks.

Effect of the storage of soybean seeds treated with agrochemicals on the physiological quality and on the seedlings morphology

Seed treatment is the most efficient technique for controlling pests and pathogens that can influence the initial development of the crop. However, storing treated seeds may damage the physiological quality. Thus, the objective of this study was to evaluate the influence of storage on the physiological quality of treated soybean seeds and on the morphology of soybean seedlings. The treatments were carried out with Fludioxonil, Imidacloprid and Anthranilic Diamide, in the dosage of 200, 150 and 100 mL of the commercial product 100 kg of seeds, respectively, from the cultivar BRSMG752S. The experimental designs used were randomized blocks (greenhouse) and completely randomized (laboratory), in a simple factorial 4x4scheme, with 4 sowing times (30, 20, 10 and 0 days after treatments) and 4 treatments (3 products and untreated seeds) with 4 repetitions. The treatment of soybean seeds with Anthranilic Diamide submitted to different storage periods was the one with the closest physiological quality to the treatment without application of agrochemicals. The soybean seeds treated with Imidacloprid showed a reduction in physiological quality with the storage time, reduction (in general) in the root length and presented a lower seedling length at 20 days of storage.

Synthesis, Physicochemical Properties, and Biological Activities of 4-(S-Methyl-N-(2,2,2-Trifluoroacetyl)Sulfilimidoyl) Anthranilic Diamide

Novel anthranilic diamides with sulfilimidoyl and sulfoximidoyl functionalities were successfully prepared. Among newly-prepared organosulfur compounds, 3-bromo-1-(3-chloropyridin-2-yl)-N-(2-methyl-6-(methylcarbamoyl)-4-(methylthio)phenyl)-1H-pyrazole-5-carboxamide and (S,E)-3-bromo-1-(3-chloropyridin-2-yl)-N-(2-methyl-4-(S-methyl-N-(2,2,2-trifluoroacetyl)sulfinimidoyl)-6-(methylcarbamoyl)phenyl)-1H-pyrazole-5-carboxamide showed good levels of efficacy and a strong correlation between insecticidal activities and physical properties, respectively. In particular, available data indicated that the N-trifluoroacetyl sulfilimine moiety could be an appealing structural scaffold for the discovery of a new crop-protecting agent.