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Microbial contaminations represent an important issue for crop production, resulting in tons of losses worldwide every year. One of the highest-risk pathogens involved in these infections is Botrytis cinerea, which is responsible for the grey mold disease. In this study, a biosurfactant extracted from corn steep liquor (CSL), an agro-industrial residue from the corn-milling industry, was used in combination with copper oxychloride (Cu-Oxy), a copper-based pesticide, to evaluate their fungitoxic activity on B. cinerea cells. The results showed that the mixture of 2 g/L of Cu-Oxy with 16 g/L of the biosurfactant extract from CSL, named biosurfactant pesticide formulation (BS-P), helped in the reduction of colony growth, in the decrease of biomass production, and in the improvement of copper bioaccumulation on fungal mycelium in comparison with aqueous solutions of commercial and pure-copper-based fungicides. A factorial design was conducted to obtain the best operational conditions for enhancing the bioaccumulation of copper by B. cinerea cells in the presence of BS-P, resulting in a maximum copper uptake of 2122 µg Cu/g dry weight when using 1 g/L of Cu-Oxy combined with 8 g/L of CSL biosurfactant extract at an incubation temperature of 15 °C. It was also proved that, due to the absence of the biosurfactant extract, the amount of copper bio-adsorbed by fungal mycelium was considerably decreased and, therefore, so was its fungitoxic activity. These results suggest that the biosurfactant extract studied could be involved in eco-friendlier pesticide formulations, reducing the environmental impact of copper-based active principles. [ABSTRACT FROM AUTHOR]

Background: This research work describes about toxicity estimation of commonly used fungicide copper oxychloride using Pisum sativum L. and Vigna radiata L. as a bioindicator. Methods: The seeds of P. sativum and V. radiata were treated with different concentrations of fungicide. Biological toxicity measured by seed germination percentage, R/P ratio, total leaf chlorophyll, total leaf proline, total seed protein, mitotic index, abnormality index and mitotic inhibition. Result: Linear regression analysis showed that seed germination percentage, total seed protein, abnormality index and mitotic inhibition show positive correlation with increasing concentration of fungicide copper oxychloride. The R/P ratio of 4th and 8th days, mitotic index, total leaf chlorophyll and leaf proline have negative correlation along increasing concentration of fungicide. However total leaf proline of V. radiata at 2% concentration of fungicide is abruptly higher than control and other concentrations. The application of copper oxychloride at lower concentration can be used as a safe fungicide. [ABSTRACT FROM AUTHOR]

Soil microorganisms exhibit varying levels of metal tolerance across a diverse range of environmental conditions. The use of metal-based fungicides such as mancozeb and copper oxychloride could potentially result in increased levels of manganese, zinc and copper which may adversely affect soil mesofauna. Under standardized earthworm bioassay conditions (temperature, pH, soil type and water content), we investigated the effect of Bacillus cereus on mancozeb and copper oxychloride ecotoxicity towards Eisenia andrei. A metal-tolerant Bacillus cereus strain previously isolated from a gold mining site was introduced into fungicide spiked soils. Earthworms were exposed to bacterial inoculated and non-inoculated substrates of mancozeb (8, 44, 800 and 1250 mg kg−1) and copper oxychloride (200, 450, 675 and 1000 mg kg−1). Experimental trials assessed avoidance-behavior, growth and reproduction utilizing standardized protocols (ISO and OECD). In the avoidance-behavior, E. andrei showed significant (p< 0.05) preference for inoculated substrates. Further, significant (p< 0.05) increases in biomass, survival, cocoons, juveniles and lower soil and tissue Mn, Cu and Zn contents were recorded at 8 and 44 mg kg−1 mancozeb and copper oxychloride 200 and 450 mg kg−1 inoculated soils compared to non-inoculated. However, at 800 and 1250 mg kg−1 mancozeb and 675 and 1000 mg kg−1 copper oxychloride concentrations, reproductive success in both inoculated and non-inoculated treatments was negatively (p< 0.05) affected. In conclusion, Bacillus cereus decreased the ecotoxicity of metal-based fungicides towards Eisenia andrei at 8 and 44 mg kg−1 mancozeb and 200 and 450 mg kg−1 copper oxychloride concentrations. The outcome observed with the inoculated substrates at elevated fungicides concentrations maybe as a result of the environmental conditions (pH and temperature). [ABSTRACT FROM AUTHOR]

Two field trials in integrated cultivation (2014 and 2016) were carried out with the aim to evaluate the efficacy and the persistence of copper oxychloride to control downy mildew of grapevine in mixture with a new natural adjuvant (PSS®) derived from locust bean (Ceratonia siliqua L.) gum. Copper amount applied in vineyards is the subject of interest for its use in organic farming due to the concern about its ecotoxicological profile in the soil that need to modify its use in rates, strategy and total amount per season. Copper oxychloride was applied every 7 and 14 days mixed or not with locust bean gum. Locust bean gum was also applied alone. To evaluate the distribution of copper on grapevine leaves, observations by scanning electron microscope were made. Locust bean gum alone did not influence the development of disease, while significantly increased efficacy and persistence of copper oxychloride both on leaves and bunches. On bunches, at 14 days interval, efficacy on incidence of copper oxychloride plus locust bean gum was about 60% while efficacy on severity was 60.1 and 65.6% for the year 2014 and 2016, respectively. With no locust bean gum, at the same interval, efficacy was significantly lower. Scanning electron microscopy demonstrated that copper fungicide particles when mixed with locust bean gum were still uniformly distributed on leaves after 14 days from application, but if applied alone already after 7 days became scattered with a lower concentration. To our knowledge, it is the first time that galactomannans-derived compounds have been used as adjuvant in pesticides. The use of locust bean gum reduced the annual amount of copper in integrated cultivation from 7.9 kg ha−1 applying copper oxychloride every 7 days to 4.5 kg ha−1 when applied every 14 days mixed with the new locust bean gum sticker. [ABSTRACT FROM AUTHOR]

Colletotrichum gloeosporioides is a serious postharvest pathogen of avocado fruits worldwide. Kenya lacks any registered fungicides for the management of the disease. Nevertheless, farmers commonly use commercially available fungicides such as Bayleton 25WP (Triadimefon 250 g/Kg), Milraz 76WP (Propineb 70% and Cymoxanil 6%), and Copper oxychloride 500WP for disease management. The efficacy of these fungicides against C. gloeosporioides is not known. The purpose of this study was therefore to test the inhibitory effect of these fungicides against 46 C. gloeosporioides isolates from avocado fruits collected from varieties grown at different agroecological zones in Murang’a County, a popular avocado-growing region in Kenya. Mycelial growth rate and sporulation for each isolate were measured in vitro on PDA plates amended with different concentrations of the fungicides. Plates were arranged in a completely randomized design with three replications per treatment. All fungicides were effective in vitro but there were significant differences in sensitivity among isolates. Bayleton had the highest mycelial inhibition followed by Milraz, while copper oxychloride had the lowest mycelial inhibition rates, ranging from 81% to 88%. However, copper oxychloride was more effective in inhibiting sporulation. The inhibitory effect of each fungicide was concentration-dependent, where twice the recommended concentration had the highest inhibitory effect, followed by the recommended concentration. Our results show that the fungicides used by farmers against C. gloeosporioides, the causal agent for anthracnose, are effective. We, however, recommend further field tests in different avocado-growing areas so as to validate their efficacy against various isolates and under different environments. [ABSTRACT FROM AUTHOR]

In the field, eggplants are frequently attacked by Alternaria porri f. sp. solani, Botrytis cinerea and Phytophthora parasitica pathogens, which diminishes yield in quantitative terms and depreciates qualitatively. For the control of these pathogens three variants of fungicide treatments with different active ingredients were tested: chlorotalonil 500 g/l, pyraclostrobin 5% + metiram 55%, metiram 80%, iprovalicarb 8.4% + Cu oxychloride 40.6%, azoxystrobin 200 g/l + diphenoconazole 125 g/l. The best efficacy was obtained at variant 2 with the following schedule of treatments: treatment 1 - pyraclostrobin 5% + metiram 55% - 0.2%; treatment 2 - iprovalicarb 8.4% + Cu oxychloride 40.6% - 0.2%; treatment 3 - pyraclostrobin 5% + metiram 55% - 0.2%; treatment 4 - iprovalicarb 8.4% + Cu oxychloride 40.6% - 0.2%; treatment 5 - azoxystrobin 200 g/l + diphenoconazole 125 g/l - 0.1%; treatment 6 - pyraclostrobin 5% + metiram 55% - 0.2%. In this variant, the average efficacy was 85.5% and the yield 39.7 t/ha (123.17%) compared to 31.8 t/ha in the untreated control variant. [ABSTRACT FROM AUTHOR]

Aspergilus flavus is the most common seed born fungus that deteriorates the seed quality and minimizes the export value of the rice all over the world. Fungicides are the most successful and commonly used way to manage any fungi but more use of fungicides have resulted evolution in the seed born fungi so efforts are required off and on to stay ahead of the fungal races. Keeping in view, the present research work was conducted to evaluate different fungicides against A. flavus and their comparative efficacy upon the infected rice seeds. Experiment was laid out in completely randomize design with varying concentrations of fungicides (20, 40, 60 and 80 ppm) under laboratory conditions. Statistical results shown significant reduction in mycelial growth and improved the seed germination as well. The results were significantly better when the fungicides were used at 80 ppm, as compared to low concentrations. Regarding mycelial growth, Kumulus-DF and Cabrio-Top were comparative to each other, followed by Trimiltox-Forte, Cordate and Copper oxychloride, while for the other attribute of infected grain germination Kumulus-DF proven better in comparison with Trimiltox-forte and Cabrio-Top, followed by Cordate and Copper oxychloride. [ABSTRACT FROM AUTHOR]

Fusarium nivale (Fr.) Ces. a recently reported fungus of mango malformation disease (MMD)is a predominant and virulent fungus in mango orchards of Sindh, Pakistan. In the current study, in vitro and in vivo attempts were made with commercial fungicides to reduce the severity of F. nivale. Mycelial growth of F. nivale was significantly inhibited at low and high doses of Thiophanate methyl and Fosetyl- Aluminium. Metalaxyl+Mancozeb and Mancozeb also reduced growth of fungus at their high doses (6.830 and 11.900mm), respectively, as compared to Copper oxychloride (18.083 mm) and control (40.750 mm). Thiophanate methyl and Fosetyl- Aluminium significantly reduced infection in Desi, Almas and Dusheri to 16.60 and 19.00%; 17.60 and 19.80%; and 20.60 and 22.00% after first spray, with decreased percent of malformation 72.33 and 68.33%; 71.11 and 67.54%; and 67.81 and 65.62% and over untreated control. The second spray of Thiophanate methyl and Fosetyl- Aluminium fungicides completely inhibited infection of F. nivale, and 100.0% reduction in malformation disease in Desi, Almas, and Dusheri as compared to Metalaxyl+Mancozeb (78.73, 73.84, 72.64%) and Mancozeb (73.65, 73.69, 69.41%), Copper oxychloride and in control. The application of Thiophanate methyl and Fosetyl- Aluminium would be useful in integrated management of MMD. [ABSTRACT FROM AUTHOR]

We assessed the effect of neutral electrolyzed water (NEW) on the incidence of rot on tomato (Solatium lycopersicum L.) fmits inoculated with Fusarium oxysporum, Galactomyces geotrichum, and Alternaria sp. at sites with lesions. The inoculated fruits were treated with NEW at 10, 30, and 60 mg liter 1 active chlorine, with copper oxychloride fungicide, and with sterile distilled water (control) for 3, 5, and 10 min. In the experiment with F. oxysporum, 50 to 80% of the control fruits and 50 to 60% of the fruits treated with the fungicide exhibited symptoms of rot at the inoculated sites. The lowest incidence recorded was 30% for fruits treated with NEW at 60 mg lite r1 active chlorine with an immersion time of 5 min. In the experiment with G. geotrichum, incidence of rot on control fmits was 70 to 90%, and for treatment with fungicide rot incidence was 50 to 90%. NEW at 60 mg lite r1 active chlorine significantly reduced incidence of symptomatic fruit: only 30% of the inoculated fruits washed for 5 min had damage from rot. In the experiment with Alternaria sp., 60 to 90% of the fruits in the control group and 60 to 70% of the fmits in the fungicide group were symptomatic. The lowest incidence was recorded for the treatment in which the fmits were submerged in NEW with 60 mg lite r1 active chlorine for 3 min. In this group, 40 to 50% of the fruits exhibited symptoms of rot. These results were obtained 8 days after inoculation. NEW, with 60 mg liter 1 active chlorine, significantly reduced incidence of rot symptoms on fmits inoculated with one of the experimental fungi relative to the control (P < 0.05). NEW at 60 mg lite r1 is effective in the control of fungal rot in tomatoes. [ABSTRACT FROM AUTHOR]

Copyright of Pesticides & Phytomedicine / Pesticidi i Fitomedicina is the property of Institute of Pesticides & Environmental Protection and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

O uso intensivo de agrotóxicos em culturas de tomates tem causado preocupações quanto à provável contaminação do produto final. Este trabalho teve como objetivo monitorar, por dois anos consecutivos, em quatro propriedades de uma área altamente tecnificada, o uso de agrotóxicos em tomate irrigado durante seu desenvolvimento, quantificar os resíduos dos principais princípios ativos utilizados, e avaliar o grau de contaminação dos frutos colhidos. Foram analisados metamidofós, clorpirifós, captan, clorotalonil, endosulfan, lambda-cialotrina, e cobre. Para avaliar o grau de contaminação dos frutos foi validado um método de análise de resíduos múltiplos capaz de quantificar esses compostos. Os resíduos encontrados foram de fungicidas e inseticidas aplicados nas fases de frutificação e maturação: captan, 0,35 mg/kg, na Fazenda 2; clorotalonil, 0,16 mg/kg e 0,95 mg/kg, nas Fazendas 1 e 2, respectivamente; lambda-cialotrina, 0,03 mg/kg, na Fazenda 2; cobre, 2,03 mg/kg, 3,75 mg/kg e 1,44mg/kg, nas Fazendas 1, 2 e 3, respectivamente, e 0,95 mg/kg, 1,70 mg/kg e 2,31 mg/kg, na Fazenda 4. Não ocorreram resíduos dos inseticidas organofosforados, aplicados principalmente durante o desenvolvimento vegetativo da cultura. Não houve contaminação dos tomates pelos agrotóxicos analisados. Os resíduos que devem ser monitorados são os dos agrotóxicos aplicados na fase de maturação da cultura.The intensive use of pesticide in tomato crops have been causing concern about a possible contamination of the final product. This work aimed at monitoring, for two years, in four farms located in a high technology area, the use of pesticides in irrigated tomato crops, quantifying the main active ingredient residues and evaluating the contamination level of the fruits. The components analised were: methamidophos, chlorpyrifos, captan, chlorothalonil, endosulfan, lambda-cyhalothrin and copper oxychloride. In order to evaluate the contamination level, a multiresidue method was validated. The residues found were from fungicides and insecticides used during the frutification and maturation stages of the crop: captan, 0.35 mg/kg, at Farm 2; chlorothalonil, 0.16 mg/kg and 0.95 mg/kg, at Farms 1 and 2, respectively; lambda-cyhalothrin, 0.03 mg/kg, at Farm 2; copper, 2.03 mg/kg, 3.75 mg/kg and 1.44 mg/kg, at Farms 1, 2 and 3, respectively, and 0.95 mg/kg, 1.70 mg/kg and 2.31 mg/kg, at Farm 4. Residues of organophosphorous components applied mainly during the vegetative growing were not found. There was no contamination in the tomatos. The residues to be monitored are those from the pesticides used in the crop maturation stage.

Excess copper in plants causes physiological alterations that lead to crop productivity losses. However, cupric fungicides have been utilized in the control of Alternaria solani and Phytophtora infestans fungi, which cause early blight and late blight in potato, respectively. Thus, this study aimed to investigate the effect of different copper oxychloride levels on potato plants through some biochemical and physiological parameters. The fungicide was applied at the recommended level (2.50 g L-1), at a reduced level (1.25 g L-1), and at 5.00 g L-1, to simulate spraying in the field twice during the same period with the recommended level. The results revealed that superoxide dismutase (SOD, EC 1.15.1.1) protected plants against oxidative stress at the beginning of the cycle since lipoperoxide levels were low in that period. In addition, increased SOD activity positively correlated with increased usable leaf area for photosynthesis (leaf area ratio, LAR), photosynthetic effectiveness (net assimilation rate, NAR), and growth relative to pre-existing dry matter (relative growth rate, RGR). Concomitantly, there was a negative correlation between lipoperoxide levels and LAR and RGR. Plants randomly sprayed twice in the same period with the level recommended for potato crop protection in the field do not present damage regarding their development. However, additional studies are needed in order to reduce the use of copper fungicides in the control of early and late blight in potato crop production, then decreasing the release of copper in the environment. [ABSTRACT FROM AUTHOR]

A 2 × 3 factorial experiment was designed to study the effect of sublethal toxicity of technical grade copperoxychloride, dietary vitamin E and their interactions on growth performance, some blood parameters, DNA fragmentation and histopathological lesions of Nile tilapia (Oreochromis niloticus). The 96 h LC50 of copperoxychloride was found to be 129.21 mg/l. Four hundred and fifty fingerlings with an average initial body weight ranged from 1.92 to 2.04 ± 0.11 g were randomly distributed equally in six treatments (T1-T6) with each of triplicates. T4, T5 and T6 were exposed to sublethal concentration 0.25 LC50 of copperoxychloride. Fish of T1, T2 and T3 fed diet supplemented with different levels of vitamin E (0, 1 and 2 g/kg diet), respectively. While fish of T4, T5 and T6 fed diet supplemented with different levels of vitamin E (0, 1 and 2 g/kg diet), respectively. At the end of the experiment (90 days) the results indicated that fish exposed to 0.25 LC50 of copperoxychloride and fed diet with normal level of vitamin E, showed significantly lower values (P\0.01) of all growth and feed utilization parameters, white blood cells and immunoglobulin M, but they showed significantly increased (P\0.05) values of alanine aminotransferase, aspartate aminotransferase, hematocrit, hemoglobin, uric acid and creatinine. Fish fed with varied concentrations of vitamin E neutralized the toxic effect of copperoxychloride as well as vitamin E, significantly lowered the hematological and biochemical response and enhanced the growth parameters and feed utilization. The toxic effect of copperoxychloride exposure and vitamin E feeding on histopathological alterations of liver and gill of the same studied fish will be taken in concern. The results showed improvement in samples treated with vitamin E. This study suggests that vitamin E can be effectively used to decrease the toxic effect of copperoxychloride on O. niloticus and its amelioration through dietary vitamin E supplementation. [ABSTRACT FROM AUTHOR]

Abstract: Inadequate disease control on citrus foliage and fruit is often attributed to insufficient fungicide spray deposition on target surfaces. This study describes a novel spray deposition assessment protocol and determines deposition benchmarks indicative of the biological effectiveness for better interpretation of spray deposition results. Suitability of a yellow fluorescent pigment as tracer for copper oxychloride deposition was demonstrated through its similar particle concentration and size. Spray deposition assessment of spray targets, which were sprayed with a mixture that included the fluorescent pigment, involved photomacrography of whole leaf or fruit surfaces, followed by digital image analyses. This protocol proved to be very accurate in determining the quantity and quality of deposition. To determine deposition benchmarks, detached young ‘Nova’ mandarin leaves were sprayed with copper oxychloride and fluorescent pigment at different concentrations (0.1–2 times the recommended concentration) and spray deposition assessed. Subsequently, leaves were spray inoculated with a spore suspension of Alternaria alternata [causal agent of Alternaria brown spot (ABS) of mandarins], moist-incubated for c. 48 h and symptom expression rated. A very good linear relationship was found between fungicide concentration, leaf area covered by fluorescent pigment particles (%FPC) (r = 0.879) and Cu residue analysis (r = 0.992). A von Bertalanffy growth curve best fitted the relation between ABS control and deposition quantity (%FPC) data (91% of the percentage variance accounted for) with a good correlation between observed and predicted values (r = 0.825). Benchmarks for 50% and 75% disease control were calculated as 2.07 %FPC and 4.14 %FPC, respectively. These corresponded with Cu residue levels of 59.4 and 91.0 mg kg−1, respectively. These FPC benchmarks can be used to evaluate spray technology research, specifically for control of ABS and similar citrus fruit and foliar diseases. [Copyright &y& Elsevier]

Copyright of Revista Ceres is the property of Revista Ceres and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The efficacy of different nutrients (CaCl2, FeSO4, MgCl2, MgSO4, KCl, KNO3, NaCl, NaNO3 & ZnSO4) and fungicides (Bavistin, Kavach, Roko, Trifen, Blitox & Indofil M-45) against the mycelial growth and conidial germination of Alternaria alternata causing leaf blight disease of mulberry was assessed at 1000 and 2000 ppm concentrations. Results revealed that Ferrous sulphate and Blitox (Copper oxychloride 50% WP) at 1000 & 2000 ppm were found effective against A. alternata under in vitro conditions. They were further evaluated individually and in combination for their efficacy against Alternaria leaf blight under field conditions. It was observed that Ferrous sulphate @ 0.2% in two foliar sprays was most effective and reduced the disease severity to an extent of 85.62% besides increasing the leaf yield up to 23.04%, which was significantly higher than that of the recommended method (two foliar sprays of 0.2% Indofil M-45). The present study indicates that, ferrous sulphate @ 0.2% in two foliar sprays can be used for effective management of Alternaria leaf blight disease in mulberry. [ABSTRACT FROM AUTHOR]

The article presents a study which examines the factors affecting the loss of pesticides sprayed on crops. It analyzes the influence of flow shear and the dosage of herbicide in the loss of colloidal-size particulate fungicides which are determined using a rotating shear system model. Further, it states that solubilisation is the main mechanism for metalaxyl loss induced by a shallow water and the erosion of copper oxychloride particles controls the loss of copper as determined by factor analysis.

The effects of the fungicide copper oxychloride on a field population of the earthworm Aporrectodea caliginosa were investigated. Changes were monitored in earthworm numbers and biomass, copper concentrations in soil and earthworms, and neutral red retention times (NRRTs) of coelomocytes. The aim was to establish whether the cellular responses could be linked to changes at the population level. Results indicated that there was a significant (P<0.05) impact on worm density and biomass on the treated plots 6 months after spraying with the fungicide stopped. NRRTs of treated earthworms were significantly lower after one spraying when earthworms had elevated concentrations of copper in their body tissues. Six months after spraying stopped, copper levels in both soil and earthworm tissues declined significantly, but the earthworm numbers and biomass were still significantly lower in the treated plots. This indicated that the effects of the copper oxychloride exposure manifested at a much later stage at the population level, than on NRRT. We conclude that the decrease in NRRTs, which preceded the decrease in both earthworm biomass and numbers, may have predictive value as a biomarker of impending population changes. [Copyright &y& Elsevier]