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Vanda is a highly valued and important orchid in the horticultural industry; however, it is usually damaged by black rot disease, caused by Phytophthora species, leading to substantial economic losses. This study aims to evaluate multiple fungicides for black rot control. Oomycetes were isolated from diseased plants, and these isolates brought about a 100% disease incidence in Vanda with water-soaked lesions, becoming necrotic within 24 h. The isolates were identified as Phytophthora palmivora based on a phylogenetic analysis of internal transcribed spacers (ITSs) and cytochrome oxidase spacer regions. For controlling black rot disease, eight fungicides or mixtures with different target sites and modes of action were screened, including cyazofamid, dimethomorph, fosetyl-aluminum, metalaxyl, thiophanate-methyl, a mixture of fluopicolide and fosetyl-aluminum, a mixture of mancozeb and valifenalate, and a mixture of quintozene and etridiazole. All tested fungicides showed 33%–100% growth inhibition using the poisoned food technique. In greenhouse experiments, seven tested fungicide formulations, except for thiophanate-methyl, exhibited 20%–66% reduced lesion sizes compared with the no-chemical control. The information on fungicides with different filicide group codes could assist a fungicide spray program for black rot management in orchids.

Sensitivity and inherent resistance risk of Alternaria solani to fludioxonil, cross-resistance profiles and the potential implications of resistance mutations on fitness parameters were investigated. Fludioxonil was highly effective against a wild type A. solani field strain both in vitro (EC50 = 0.05 μg/mL) and in preventive applications on artificially inoculated tomato fruit. Mutants with low [Resistance factor (Rf): 15 based on EC50], medium (Rf: 150–300) and high (Rf: > 1000) levels of phenylpyrrole resistance were isolated from the wild type strain at high frequencies following mutagenesis with UV irradiation and selection on fludioxonil containing medium. Resistant isolates retained their resistance levels even after 9 subcultures on fungicide-free growth medium while they could express their resistant phenotypes in planta. Investigation of cross-resistance relationships showed that fludioxonil resistance mutations also reduce the sensitivity of mutant strains to the aromatic hydrocarbon fungicide quintozene as well as the dicarboximides iprodione and vinclozolin. No cross-resistance was observed between fludioxonil and fungicides with different modes of action such as the sterol biosynthesis inhibitors (DMIs) imazalil and flusilazole and the carboxamide boscalid. All fludioxonil resistant isolates were more sensitive to the anilinopyrimidine pyrimethanil, while only two isolates were less sensitive to the QoI pyraclostrobin compared to the wild-type strain. Study of fitness determining parameters showed that resistance mutation(s) had no adverse effects on mycelial growth, conidial germination and sensitivity to osmotic stress while they had a pleiotropic effect on virulence and conidia production in resistant mutants. Results of the present study indicate that fludioxonil is a highly effective fungicide against A. solani, while the risk of resistance development to this fungicide is considered to be medium making fludioxonil an ideal alternative to high risk fungicides such as boscalid and pyraclostrobin whose performance against early blight has already been compromised by resistance development.

Pesticides and nanoparticles may coexist in soil; however, influences of nanoparticles on accumulation of pesticides in terrestrial organisms are still unclear. This study aims to investigate the influences and mechanisms of metal oxide nanoparticles (nano ZnO and nano CuO) on accumulation of pentachloronitrobenzene (PCNB) in earthworms and their combined toxicity. The earthworms were cultivated in the soil spiked with nanoparticles (10, 50, 250 mg/kg) and PCNB (100 μg/kg) for 21 days. The concentrations of PCNB in earthworms in binary exposure treatments (PCNB + ZnO and PCNB + CuO) reached 2.47 and 3.13 times of that in individual PCNB exposure treatment, indicating that nanoparticles facilitated the accumulation of PCNB in earthworms. The contents of reactive oxygen species (ROS) in earthworms in treatments PCNB + ZnO 250 and PCNB + CuO 250 reached 379 and 316 fluorescence intensity/mg Protein, respectively, which were significantly higher than that in control group (183 fluorescence intensity/mg protein), indicating that nanoparticles would cause oxidative stress to earthworms. Earthworm coelomocytes were extracted from healthy earthworms and cultivated in culture media in cytotoxicity tests. Changes of intracellular ROS contents and cell viability suggested that PCNB and nanoparticles caused serious oxidative damage to earthworm coelomocytes, thus leading to the damage of cell membrane and cell death. In in vivo tests, changes of biomarkers (ROS and malondialdehyde) demonstrated that these pollutants injured the earthworms. Increased accumulation of PCNB in binary exposure treatments was due to the damage of body cavity caused by nanoparticles. This study provides a novel hypothesis for nanoparticles facilitating organic pollutants entering terrestrial organisms and determines whether nanoparticles would bring about greater environmental risks of other pollutants.

Several challenges persist in China’s ginseng industry. Phoxim, chlorpyrifos, quintozene—unregistered pesticides primarily used as soil insecticides and fungicides—may pose high dietary risks. This study performed a thorough screening of potential pesticides used in Chinese ginseng cultivation, evaluated the long-term dietary risks for the ginseng-consuming group, and used the primary risk factors for ginseng in China and South Korea to compare the two nations’ pesticide usage scenarios. From 2020 to 2022, 325 pesticides and related compounds were screened in 15 major ginseng-producing counties and 3 commercial markets in Northeast China, and 39 pesticides and 3 metabolites were identified using gas chromatography–tandem mass spectrometry and liquid chromatography–tandem mass spectrometry, including allylmorph, pyrimethanil, pyraclostrobin, and other contaminants in Northeast China. Acute and chronic dietary risk assessment was performed using 0.009 kg as the maximum daily intake and 0.005 kg as the average daily intake, with adults as the exposed population. Based on these findings and reliable toxicological data, acute and chronic dietary risk quotients for ginseng were assessed, considering dietary intake and population exposure. The results indicate that ginseng products are generally safe and manageable, with acute and long-term dietary risks remaining within acceptable limits.

The purpose of this study was to investigate the status of organochlorine pesticide residues in 186 ginseng samples collected in Jilin, People's Republic of China. Based on the 2015 method for detection of organochlorine pesticide residues in ginseng, 22 organochlorine pesticide residues were identified. Chlordane, aldrin, epichlorohydrin, and dieldrin and their isomers were not detected in ginseng from this region. Heptachlor was detected in only one ginseng sample, and the concentration did not exceed the maximum residual limit (MRL) prescribed in the (0.05 mg/kg). Benzene hexachloride was detected in two samples, one of which was above the MRL. Hexachlorobenzene and pentachloronitrobenzene (quintozene) were found in 11.8 and 52.1% of the samples, respectively, and the residues in these samples exceeded the MRL by 4.3 and 8.6%, respectively.

Due to the widespread use of pesticides, human exposure to pesticides is possible and can potentially cause adverse impacts on public health. We measured 137 pesticides including organophosphorus, organochlorine, pyrethroid and carbamate pesticides together with various herbicides in 100 human blood samples collected from the general population in Beijing. The samples were analysed by triple quadrupole tandem gas chromatography-mass spectrometry. In total, 24 organochlorine pesticides, 5 pyrethroid pesticides and 6 organophosphorus pesticides were detected. The detection rates of HCB, α-HCH, β-HCH, γ-HCH, p,p′-DDE and quintozene were 99, 96, 74, 72, 96 and 95%, respectively. No statistically significant gender difference in the blood concentrations of the pesticides was found. Consistent with the trend of the increasing β-HCH, p,p′-DDE and quintozene concentrations with age, a strong positive correlation between the age and concentrations of β-BHC, p,p′-DDE and quintozene was observed.

Organochlorine pesticides (OCPs) are a pressing global issue, particularly in developing countries like Egypt. These pervasive pesticides pose an environmental and public health concern in Egypt due to their historical use and frequent identification in soils, water bodies, and food products. These present a potential long-term risk to human health and ecosystems. We collected water and Nile tilapia ( Oreochromis Niloticus ) samples in four Egyptian governorates: Alexandria, Port Said, Ismailia, and Faiyum. Our analysis, through using gas chromatography/mass spectrometry, spans 17 OCPs in depth. Our study revealed that certain OCPs, such as Heptachlor, Aldrin, Pentachloronitrobenzene, Heptachlor epoxide, and β -Endosulfan, are consistently found in higher concentrations among the 17 pesticides tested. Seasonal spikes were identified, particularly in Ismailia, Faiyum, and Alexandria, marking them as environmental risk hotspots. Certain OCPs demonstrated distinctive seasonal variations, such as 4,4′-DDE in Faiyum. Heptachlor, β -HCH, Endrin, and α -Endosulfan exhibited significant changes solely in Ismailia, while α -HCH, Heptachlor epoxide, and γ -HCH showed unique seasonal patterns only in Alexandria. The risk quotient (RQ) analysis highlighted that Aldrin, Heptachlor, 4,4′-Dichlorodiphenyltrichloroethane, and 2,4′-Dichlorodiphenyltrichloroethane pose a high environmental risk in all governorates, while 4,4′- Dichlorodiphenyltrichloroethane showed high risk only in Port Said (RQ > 1). Several OCPs posed an ecological risk with an RQ > 1. In addition, our results emphasized that there is negligible non-carcinogenic risk associated with dermal water exposure or the consumption of Nile tilapia. There is, however, a minor risk of cancer associated with consuming Nile tilapia or dermal exposure. Therefore, we recommend advocating for strict regulations, implementing monitoring programs, initiating public health initiatives, adopting effective alternatives, developing new remediation approaches, conducting long-term and association studies, and examining the consequences of climate change on the persistence of OCPs in the environment.

A method was established for the simultaneous determination of 116 pesticide residues in Notoginseng Radix et Rhizome with a combination of the modified QuEChERS method and GC–MS/MS. The sample was extracted with acetonitrile, cleaned up by primary–secondary amine and octadecyl-modified silica (C18) sorbents and determined by GC–MS/MS in multireaction monitoring mode. Matrix-matched calibration coupled with internal standard method was applied to compensate for the matrix effect and to quantify the pesticides. The results of all the 116 pesticides showed good linearity in the respective linear range with correlation coefficients (r2) > 0.99. The method limits of quantification were between 0.01 and 0.05 mg kg−1. The recoveries were between 64.3 and 119.4%, with RSD values typically lower than 18.3% at three spiked levels of 0.05, 0.10 and 0.20 mg kg−1. The validated methodology is easy, fast, highly accurate, reliable and sensitive for monitoring and quantification of the 116 pesticide residues in Notoginseng Radix et Rhizoma. In 180 batches of real samples, 11 pesticides were detected and among these quintozene and cyfluthrin were in excess of the standard of European Union maximum residue level for herbs.

Pentachloronitrobenzene (PCNB) is a toxic chlorinated nitroaromatic compound. However, only a few bacteria have been reported to be able to utilize PCNB. In the present study, one pentachloronitrobenzene (PCNB)-degrading bacterium, Cupriavidus sp. YNS-85, was isolated from a contaminated Panax notoginseng plantation. The strain co-metabolized 200 mg L −1 PCNB in aqueous solution with a removal rate of 73.8% after 5 days. The bacterium also degraded PCNB effectively under acid conditions (pH 4–6) and showed resistance to toxic trace elements (arsenic, copper, and cadmium). Its ability to utilize proposed PCNB intermediates as sole carbon sources was also confirmed. The soil microcosm experiment further demonstrated that bacterial bioaugmentation enhanced the removal of PCNB (37.8%) from soil and the accumulation of pentachloroaniline (89.3%) after 30 days. Soil enzyme activity and microbial community functional diversity were positively influenced after bioremediation. These findings indicate that Cupriavidus sp. YNS-85 may be a suitable inoculant for in situ bioremediation of PCNB-polluted sites, especially those with acid soils co-contaminated with heavy metal(loid)s.

Nowadays, nanocarbon is widely employed to enwrap into fertilizers. However, the influence of nanocarbon on the transportation of contaminants from soil to plants and its mechanism remain unclear. In this study, pentachloronitrobenzene (PCNB), a typical organochlorine fungicide utilized all over the world, was chosen as the target contaminant to investigate the influence of nanocarbon on its transportation in soil-pak choi system. The maximum PCNB concentration in the root and leaf reached to 112 and 86 ng/g, respectively, demonstrating that PCNB would be absorbed by pak choi. The ratio of PCNB between leaf and root indicated that nanocarbon promoted root of pak choi to absorb PCNB. The transportation of PCNB inside plant was inhibited when pak choi was planted in soil containing higher concentration of nanocarbon. Human risk assessment showed that people consuming the pak choi in this study would not experience risk. However, in vitro toxicity test indicated that PCNB could directly impair intestinal epithelial cells (Caco-2 cells) and thus pose a potential risk to human intestine.