nabam and metalaxyl

Mancozeb and metalaxyl are fungicidal agents frequently used in combination to control fungi in crops that may affect non-target organisms when entering ecosystems. This study aims to evaluate the environmental effects of Mancozeb (MAN) and Metalaxyl (MET), alone and in combination, on zebrafish (Danio rerio) as an experimental model. The oxidative stress biomarkers and the transcription of genes involved in detoxification in zebrafish (Danio rerio) were assessed after co-exposure to MAN (0, 5.5, and 11 μg L

Topics: Animals; Antioxidants; Ecosystem; Fungicides, Industrial; Oxidative Stress; Water Pollutants, Chemical; Zebrafish

Topics: Alanine; Animals; Cattle; Cells, Cultured; Female; Fungicides, Industrial; Luteal Cells; Maneb; Progesterone; Triazoles; Zineb

Arbuscular mycorrhizal fungi (AMF) are mutualistic symbionts considered a key group in soil systems involved in the provision of several ecosystem services. Recently they have been listed by EFSA as organisms to be included in the test battery for the risk assessment of plant protection product (PPPs). This study aimed to contribute to improve the ISO Protocol (ISO 10832: 2009) by assessing the feasibility of using other AMF species under different test conditions. Overall, results showed that AMF species Gigaspora albida and Rhizophagus clarus (selected out of five AMF species) are suitable to be used in spore germination tests using the ISO protocol (14 days incubation with sand or artificial soil as substrate) to test PPPs. However, several modifications to the protocol were made in order to accommodate the use of the tested isolates, namely the incubation temperature (28 °C instead of 24 °C) and the change of reference substance (boric acid instead of cadmium nitrate). The need for these changes, plus the results obtained with the three fungicides tested (chlorothalonil, mancozeb and metalaxyl-M) and comparisons made with literature on the relevance of the origin of AMF isolates in dictating the adequate test conditions, emphasize the importance of adjusting test conditions (AMF species/isolates and test temperature) when assessing effects for prospective risk assessment targeting different climatic zones. So, further studies should be conducted with different AMF species and isolates from different climatic regions, in order to better define which species/isolate and test conditions should be used to assess effects of a particular PPP targeting a given climatic zone.

Topics: Alanine; Fungicides, Industrial; Glomeromycota; Maneb; Mycorrhizae; Nitriles; Risk Assessment; Soil; Soil Microbiology; Temperature; Time Factors; Toxicity Tests; Zineb

To compare the side-effects of chemical versus biofungicides on non-target organisms in agricultural soil, a study of population structure, spatial distribution and fecundity of oribatid mites, a diverse and species-rich group of microarthropods indicative of decomposer activity in soil was done. Plots laid out in agricultural fields of a research station in Egypt, were cultivated with cucumber and treated with two chemical fungicides: Ridomil Plus 50% wp (active ingredients=metalaxyl and copper oxychloride) and Dithane M-45 (active ingredient=mancozeb), and two biofungicides: Plant Guard (containing the antagonistic fungus Trichoderma harzianum) and Polyversum (containing the fungi-parasitic oomycete Pythium oligandrum). All treatments were done using both low-volume and high-volume spraying techniques to check whether any effects were dependent on the method of application. Oribatid mite communities were assessed from soil core samples collected during the growing season. Total abundance of oribatids was not different across the plots, but some species decreased in number, while one species increased. Species diversity and community equitability decreased with the application of chemical and biofungicides especially when using high-volume spraying. In control plots most oribatid species showed a significant degree of aggregation, which tended to decrease under fungicide treatment. Ridomil Plus, Plant Guard and Polyversum had a negative effect on the gravid/ungravid ratio of some species. Egg number averaged over the whole adult population was not directly related to the application of chemical and biofungicides but it showed a species-specific relationship with population density. In general biofungicides had a smaller effect on population size and community structure of oribatid mite species than chemical fungicides. The results indicate that biofungicides may be the preferred option when aiming to prevent side-effects on sensitive groups among the species-rich soil detritivore community.

Topics: Agriculture; Alanine; Animals; Biological Control Agents; Biota; Copper; Cucumis sativus; Egypt; Fungicides, Industrial; Maneb; Mites; Population Dynamics; Pythium; Reproduction; Soil; Trichoderma; Zineb

Dissipation of mancozeb and metalaxyl in tomato was estimated following four applications of a combination formulation Ridomil MZ (mancozeb 64% + metalaxyl 8%) at 0.25 and 0.50% at 10 days interval by carbon disulphide evolution method and gas liquid chromatography with nitrogen phosphorous detector, respectively. Half-life periods for mancozeb were 3.76 and 4.14 days, whereas for metalaxyl these values were 1.29 and 0.41 days at single and double the application rates, respectively. Residues of mancozeb dissipated below limit of quantification (LOQ) of 0.25 mg kg(-1) after 10 and 15 days at single and double the application dosage, respectively. Similarly, residues of metalaxyl took 3 and 5 days to reach LOQ of 0.02 mg kg(-1), at single and double dosages, respectively.

Topics: Alanine; Chromatography, Gas; Half-Life; Limit of Detection; Maneb; Pesticide Residues; Solanum lycopersicum; Zineb

A study of the in vitro sensitivity of 12 isolates of Phytophthora infestans to metalaxyl, azoxystrobin, dimethomorph, cymoxanil, zoxamide and mancozeb, was conducted. The isolates derived from infected potato leaves collected at eight different localities in Serbia during 2005-2007. The widest range of EC(50) values for mycelial growth of the isolates was recorded for metalaxyl. They varied from 0.3 to 3.9 μg mL(-1) and were higher than those expected in a susceptible population of P. infestans. The EC(50) values of the isolates were 0.16-0.30 μg mL(-1) for dimethomorph, 0.27-0.57 μg mL(-1) for cymoxanil, 0.0026-0.0049 μg mL(-1) for zoxamide and 2.9-5.0 μg mL(-1) for mancozeb. The results indicated that according to effective concentration (EC(50)) the 12 isolates of P. infestans were sensitive to azoxystrobin (0.019-0.074 μg mL(-1)), and intermediate resistant to metalaxyl, dimethomorph and cymoxanil. According to resistance factor, all P. infestans isolates were sensitive to dimethomorph, cymoxanil, mancozeb and zoxamide, 58.3% of isolates were sensitive to azoxystrobin and 50% to metalaxyl. Gout's scale indicated that 41.7% isolates were moderately sensitive to azoxystrobin and 50% to metalaxyl.

Topics: Acetamides; Alanine; Amides; Maneb; Methacrylates; Morpholines; Pesticides; Phytophthora infestans; Plant Diseases; Pyrimidines; Serbia; Solanum tuberosum; Strobilurins; Zineb

The persistence of fungicides on two commercial cultivars of potato was determined under field conditions at Punjab Agricultural University, Ludhiana, Punjab. Initial deposits of mancozeb on potato leaves were found to be 26.9 and 38.7 mg kg(-1), following application of ready mixture of fungicide metalaxyl 8% + mancozeb 64% (Ridomil MZ) at the rate of 1260 and 2520 g a.i. ha(-1), whereas metalaxyl residues were found to be 35.1 and 49.5 mg kg(-1), respectively. The residue level of mancozeb in potato leaves 15 days after application at single and double doze were 19.0 and 27.0 mg kg(-1) showing a loss of 29.6 and 30.3%, whereas the values for metalaxyl at single and double doze were 0.40 and 0.80 mg kg(-1) showing a loss of 98.9 and 98.4%, respectively. Residues of mancozeb and metalaxyl were not detected at 0.04 and 0.02 mg kg(-1) level in potato tubers at harvest (PHI = 53 days) at both the dosages, respectively. The persistence and dissipation of mancozeb with the application of Ridomil MZ followed similar trend as in Indofil M-45. The rate of fungicide dissipation increased with time after application in both the potato cultivars 'Kufri Chandramukhi' and 'Chipsona'. No significant difference was observed on initial deposit, persistence and dissipation of the two molecules between the two potato cultivars.

Topics: Alanine; Fungicides, Industrial; Humans; Maneb; Pesticide Residues; Plant Diseases; Plant Leaves; Soil Pollutants; Solanum tuberosum; Zineb

Isolates of Cladobotryum dendroides from Serbian mushroom farms and Agaricus bisporus F56 were tested for sensitivity to selected fungicides in vitro. Chlorothalonil was the most toxic fungicide to C. dendroides isolates (EC(50) values were below 1.68 mg L(-1)). Trifloxystrobin and kresoxim-methyl were not effective in growth inhibition of C. dendroides isolates (EC(50) values exceeded 300 mg L(-1)). Metalaxyl-M+mancozeb was the most toxic fungicide to strain F56 of A. bisporus, and iprodione the least toxic. The fungicide selectivity indexes for both C. dendroides and A. bisporus indicated that iprodione, chlorothalonil, captan and metalaxyl-M+mancozeb had satisfactory selective fungitoxicity. Iprodione had the best selectivity to both the pathogen and the host, although inferior than prochloraz manganese and carbendazim, fungicides officially recommended for mushroom cultivation in European Union (EU) countries.

Topics: Acetates; Agaricus; Alanine; Aminoimidazole Carboxamide; Captan; Fungicides, Industrial; Hydantoins; Hypocreales; Imines; Lethal Dose 50; Maneb; Methacrylates; Nitriles; Phenylacetates; Serbia; Strobilurins; Zineb

The degradation pattern of metalaxyl, mancozeb and its metabolite ethylenethiourea (ETU) residues indicated a close correspondence to first order exponential degradation kinetics in soils. Degradation of fungicides in soils was predominantly biological as well as chemical in nature. Slower degradation ofmetalaxyl was noticed in the soils and their half-life values were higher than mancozeb and ETU as evident by wide range of half-life values from 41.24 to 165.11 days. In case of metalaxyl, Hiriyur soil was found to be superior in degrading the metalaxyl. Lower persistence of mancozeb and ETU was observed in soils resulting in rapid rate of degradation at smaller half-life values as compared to metalaxyl indicating the faster degradation of mancozeb and ETU. In mancozeb applied soils, the ETU formation was increased up to 30 days of incubation and thereafter it declined. Amongsoils, degradation of either mancozeb or ETU is not influenced by soil types. However, mancozeb persistence was higher in Hiriyur soils than Chettalli and Bangalore soils.

Topics: Agriculture; Alanine; Biodegradation, Environmental; Ethylenethiourea; Fungicides, Industrial; Humans; Maneb; Soil Pollutants; Zineb

Cyazofamid (ISO proposed common name), 4-chloro-2-cyano-N,N-dimethyl-5-p-tolylimidazole-1-sulfonamide is a novel fungicide exhibiting specific activity against diseases caused by Oomycetes. In tests, cyazofamid at 0.4-1.6 mg litre-1 exhibited excellent preventative activity against Phytophthora infestans on tomato and Pseudoperonospora cubensis on cucumber. Minimum inhibitory concentrations of cyazofamid against both diseases were over 63 times lower than those of mancozeb and at least 16 times lower than those of metalaxyl. Cyazofamid at 1.6-25 mg litre-1 exhibited not only preventative activity, but also stable residual activity and rainfastness. Cyazofamid at 6.3 mg litre-1 reduced zoosporangia formation of P infestans and P cubensis on host plants by 100 and 94% respectively. Cyazofamid also exhibited translaminar and curative activity. Cyazofamid has a new mode of action for fungicides and exhibits no cross-resistance with other currently registered and commonly used fungicides. These properties lead to a high level control by cyazofamid in field.

Topics: Alanine; Animals; Cucumis sativus; Dose-Response Relationship, Drug; Fungicides, Industrial; Imidazoles; Maneb; Microbial Sensitivity Tests; Molecular Structure; Oomycetes; Phytophthora; Solanum lycopersicum; Sulfonamides; Zineb

It has been found that Phytophthora cactorum mainly infects ginseng roots and causes phytophthora roots rot without symptoms on the leaves. The results of fungistatic test indicate that mycelial growth of the pathogen can be inhibited completely by Mancozeb and Metalaxyl at 100 ppm in vitro.

Topics: Alanine; Maneb; Panax; Plant Diseases; Plants, Medicinal; Zineb