Уточнить поиск
Результаты 1-5 из 5
Synergistic effects of glyphosate formulation herbicide and tank-mixing adjuvants on Pardosa spiders
2019
Niedobová, Jana | Skalský, Michal | Ouředníčková, Jana | Michalko, Radek | Bartošková, Adéla
Glyphosate-based herbicides are the world’s most consumed agrochemicals, and they are commonly used in various agroecosystems, including forests, as well as in urban zones and gardens. These herbicides are sold as formulations containing adjuvants. Other tank-mixing adjuvants (most often surfactants) are commonly added to these formulations prior to application. According to the manufacturers of agrochemicals, such tank mixes (as these are known in agronomic and horticultural practice) have modified properties and perform better than do the herbicides as used alone. The effects of these tank mixes on the environment and on beneficial arthropods are almost unknown. Therefore, we studied whether a herbicide formulation mixed with adjuvant has modified effects on one of the most common genera of ground-dwelling wolf spiders vis-à-vis the herbicide formulation and adjuvants themselves. Specifically, we studied the synergistic effect in the laboratory on the predatory activity (represented by the number of killed flies) of wolf spiders in the genus Pardosa after direct treatment using the glyphosate-based herbicide formulation Roundup klasik Pro®, Roundup klasik Pro® in a mixture with the surfactant Wetcit®, Roundup klasik Pro® in a mixture with the surfactant Agrovital®, and the surfactants alone. We found that pure surfactants as well as herbicide-and-surfactants tank mixes significantly decrease the predatory activity of Pardosa spiders in the short term even as Roundup klasik Pro® did not itself have any such effect. Our results support the hypothesis that plant protection tank mixes may have modified effect on beneficial arthropods as compared to herbicide formulations alone. Therefore, testing of pesticide tank mixes is highly important, because it is these tank mixes that are actually applied to the environment.
Показать больше [+] Меньше [-]Toxic effects of hexaflumuron on the development of Cocccinella septempunctata
2014
Caihong, Yu | Maoran, Fu | Ronghua, Lin | Yan, Zhang | Liu, Yongquan | Hui, Jiang | Brock, T.C.M.
Studying the toxic risk of pesticide exposure to ladybird beetles is important from an agronomical and ecological perspective since larval and adult ladybirds are dominant predators of herbivorous pest insects (e.g., aphids) in various crops in China. This article mainly deals with the long-term effects of a single application of the insect growth regulator hexaflumuron on Coccinella septempunctata. A 72- h and a 33-day toxicity test with hexaflumuron (single application) were performed, starting with the second instar larvae of C. septempunctata. Exposure doses in the long-term experiment were based on the estimated 72-h acute LR50 (application rate causing 50 % mortality) value of 304 g active ingredient (a.i.) ha-1 for second instar larvae of C. septempunctata. The long-term test used five hexaflumuron doses as treatment levels (1/50, 1/100, 1/200, 1/400, and 1/800 of the 72-h acute LR50), as well as a solvent control and blank control treatment. The measurement endpoints used to calculate no observed effect application rates (NOERs) included development time, hatching, pupation, adult emergence, survival, and number of eggs produced. Analyzing the experimental data with one-way analysis of variance showed that the single hexaflumuron application had significant effects on C. septempunctata endpoints in the 33-day test, including effects on development duration (NOER 1.52 g a.i. ha-1), hatching (NOER 3.04 g a.i. ha-1), pupation (NOER 3.04 g a.i. ha-1), and survival (NOER 1.52 g a.i. ha-1). These NOERs are lower than the reported maximum field application rate of hexaflumuron (135 g a.i. ha-1) in cotton cultivation, suggesting potential risks to beneficial arthropods.
Показать больше [+] Меньше [-]Sublethal effects of anthranilic diamide insecticides on the demographic fitness and consumption rates of the Coccinella septempunctata (Coleoptera: Coccinellidae) fed on Aphis craccivora
2020
Jiang, Jiangong | Wang, Yao | Mu, Wei | Zhang, Zhengqun
As for developing effective integrated pest management (IPM), it is necessary to understand the sublethal effects of common insecticides on the non-target beneficial arthropods. In this lab-scale study, the sublethal effects of two anthranilic diamide insecticides chlorantraniliprole and cyantraniliprole on the populations of 7-spot ladybird Coccinella septempunctata (Coleoptera: Coccinellidae) were determined and compared using an age-stage, TWO-SEX life table and CONSUME-MSChart computer program. Cyantraniliprole at low-lethal concentrations of 1 and 10 mg L⁻¹ significantly prolonged the larval stages and reduced the total adult longevity, compared with the control. Additionally, the net reproductive rate (R₀), intrinsic rate of increase (r), finite rate of increase (λ), and mean generation time (T) were significantly reduced in the group treated with 10 mg L⁻¹ of cyantraniliprole. Similarly, the net predation (C₀), the finite predation rate (ω), and stable predation rate (ψ) were significantly reduced by cyantraniliprole at 1 and 10 mg L⁻¹. In contrast, no significant difference in the demographic parameters above was determined for chlorantraniliprole at 1 mg L⁻¹. Therefore, C. septempunctata population may develop faster and possess greater predation potential against aphids under the exposure of chlorantraniliprole, compared to cyantraniliprole. Chlorantraniliprole may be a preference to cyantraniliprole as a combined alternative with ladybeetle predators in IPM framework.
Показать больше [+] Меньше [-]Favorable compatibility of nitenpyram with the aphid predator, Coccinella septempunctata L. (Coleoptera: Coccinellidae)
2018
Jiang, Jiangong | Ma, Dicheng | Zhang, Zhengqun | Yu, Caihong | Liu, Feng | Mu, Wei
The increasing demand for lessening the chemical input in agricultural ecosystems requires an efficient combination of pesticides and biological controls. Thus, fully understanding the compatibility of pesticides and beneficial arthropod predators is helpful and essential. In this study, we evaluated the influence of nitenpyram on both larvae and adults of Coccinella septempunctata using exposure doses of 10, 25, 50, 100, and 150% of the maximum recommended field rate (MRFR) (3, 7.5, 15, 30, and 45 g a.i. ha⁻¹, respectively) and a blank control based on a preliminary acute 72-h toxicity experiment. In the long-term test, the LR₅₀ (application rate causing the mortality of 50% of the individuals) of nitenpyram for C. septempunctata decreased from 73.43 to 63.0 g a.i. ha⁻¹, while the HQ (hazard quotient) values remained below the threshold value of 2. Nitenpyram did not significantly influence the survival rate, fecundity, pupation, or adult emergence at 150% of the label rate (lowest LR₅₀ = 63.0 g a.i. ha⁻¹), and its demonstrated NOER (No Observed Effect application Rates) values are all above 45 g a.i. ha⁻¹. Likewise, the total developmental time and egg hatchability were not significantly affected at 100% of the label rate (NOER = 30 g a.i. ha⁻¹). The assessment of the total effect (E) suggested that nitenpyram could be classified as harmless to C. septempunctata below/at a dose of 30 g a.i. ha⁻¹. The lowest LR₅₀ and NOER values were both above the maximum recommended field application rate for nitenpyram (30 g a.i. ha⁻¹) for controlling aphids in China. All results indicated that the on-label use of nitenpyram is compatible with the natural enemy C. septempunctata in agricultural ecosystems.
Показать больше [+] Меньше [-]Toxic effects of hexaflumuron on the development of Coccinella septempunctata
2014
Yu, Caihong | Fu, Maoran | Lin, Ronghua | Zhang, Yan | Yongquan, Liu | Jiang, Hui | Brock, Theo C. M.
Studying the toxic risk of pesticide exposure to ladybird beetles is important from an agronomical and ecological perspective since larval and adult ladybirds are dominant predators of herbivorous pest insects (e.g., aphids) in various crops in China. This article mainly deals with the long-term effects of a single application of the insect growth regulator hexaflumuron on Coccinella septempunctata. A 72-h and a 33-day toxicity test with hexaflumuron (single application) were performed, starting with the second instar larvae of C. septempunctata. Exposure doses in the long-term experiment were based on the estimated 72-h acute LR₅₀(application rate causing 50 % mortality) value of 304 g active ingredient (a.i.) ha⁻¹for second instar larvae of C. septempunctata. The long-term test used five hexaflumuron doses as treatment levels (1/50, 1/100, 1/200, 1/400, and 1/800 of the 72-h acute LR₅₀), as well as a solvent control and blank control treatment. The measurement endpoints used to calculate no observed effect application rates (NOERs) included development time, hatching, pupation, adult emergence, survival, and number of eggs produced. Analyzing the experimental data with one-way analysis of variance showed that the single hexaflumuron application had significant effects on C. septempunctata endpoints in the 33-day test, including effects on development duration (NOER 1.52 g a.i. ha⁻¹), hatching (NOER 3.04 g a.i. ha⁻¹), pupation (NOER 3.04 g a.i. ha⁻¹), and survival (NOER 1.52 g a.i. ha⁻¹). These NOERs are lower than the reported maximum field application rate of hexaflumuron (135 g a.i. ha⁻¹) in cotton cultivation, suggesting potential risks to beneficial arthropods.
Показать больше [+] Меньше [-]