Fungicide Performance

In particular, growers are concerned about the risk of resistance, which first emerged as a serious problem in the 1970s following the introduction and extensive use of systemic fungicides. The problem affects the grower and fungicide manufacturer because of the loss in profit. Potentially, it affects consumers because of the eventual reduction in food variety and quality, and increased prices. It is the ever present 

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Professor Filhr discussed penetration, translocation and distribution of fungicides in plants. These aspects of fungicide performance are often critical in determining the success of a systemic fungicide in a particular type of application. The ability to penetrate into plant tissue and move while retaining activity therein is the primary basis for the superiority of the newer systemic fungicides over the older surface protectants. Internal therapeu-tants may also influence the host physiology and as a consequence, be assisted by the natural defense system of the host. 

Steurbaut W, Megahed HS, Van Roey G, Melkebeke T and Dejonckheere W Improvement of fungicide performance by the addition of surfactants to the formulations, Part II Influence on biological and systemic activity, Med. Fac. Landbouww. Rijksuniv. Gent 54 219-232 (1989). 

As part of a series of experiments to investigate the reasons for the changes in fungicide performance, laboratory degradation studies were made initially with iprodione. Carbon-14 labelled... 

The almost exclusive use of tria2oles foi ceieal powdery mildew control up to the mid-1980s has resulted in a shift in E.Tysiphe populations toward reduced sensitivity or resistance to this class of fungicides. However, use has continued because field performance of most tria2oles has remained adequate (43). Decreased a2ole sensitivity in the population to a2oles has also been noted. 

Aliphatic Isocyanates. Aflphatic diisocyanates have traditionally commanded a premium price because the aflphatic amine precursors ate mote expensive than aromatic diamines. They ate most commonly used in appHcafions which support the added cost or where the long-term performance of aromatic isocyanates is unacceptable. Monofuncfional aflphatic isocyanates, such as methyl and -butyl isocyanate, ate used as intermediates in the production of carbamate-based and urea-based insecticides and fungicides (see Fungicides, agricultural Insectcontroltechnology). 

Clark, T, Clifford, D.R., Deas, A.H.B., Gendle, R, and Watkins, D.A.M. Photolysis, metabolism, and other factors influencing the performance of triadimefon as a powdery mildew fungicide, Pestic. Sci., 9(6) 497-506, 1978. 

Cloud point extraction has been applied to the separation and preconcentration of analytes including metal ions, pesticides, fungicides, and proteins from different matrices prior to the determination of the analyte by techniques such as atomic absorption, gas chromatography, high performance liquid chromatography, capillary zone electrophoresis, etc. 

Klupinski et al. (2004) report a laboratory experiment on the degradation of a fungicide, pentachloronitrobenzene (C Cl NO ), in the presence of goethite and iron oxide nanoparticles this study was intended to illustrate the fate of organic agrochemical contaminants in an iron-rich subsurface. To compare the effects of iron with and without a mineral presence, experiments were performed using... 

A method has been developed for the analysis of the fungicide TBZ in fruits, potatoes, and their processed products. Extraction was performed with a basic solution (ethanol with 2 M ammonium chloride, pH 9.5, with 14.5 M ammonium hydroxide) and methylene chloride. Tribendazole was partitioned into methylene chloride with a polytron. No further cleanup was needed. Total analysis time, including extraction, was 25 min per sample. Recoveries ranged from 77 to 135%. Detection limits were 1.0 ppb for juice, fruits, and potatoes and 2 ppb for bulk concentrates (12). 

Benzimidazole carbamates are usually analyzed by HPLC. Different stationary phases have been assayed, and alkyl-bonded-silica-based phases have generally been considered the most useful separation mode, although polymer-based columns performed better in separating benzimidazole fungicides (20). Buffered water and methanol (124,20) or acetonitrile (125) have been used as mobile phases. 

P Cabras, P Diana, M Meloni, FM Pirisi. Residue determination of some insecticides and fungicides on grapes by reversed-phase high-performance liquid chromatography. J Agric Food Chem 30 569-527, 1982. 

Fentin, cyhexatin and fenbutatin oxide fungicides have been determined in soil by high-performance liquid chromatography with a CN column combined with UV photoconversion and post-column morin complexation followed by fluorescence detection [539]. 

Hickey, K.D., and Yoder, K.S. 1981. Field Performance of sterol-inhibiting fungicides against apple powdery mildew in the mid-Atlantic apple growing region. Plant Dis. 65 1002-1006. 

Tetraalkylthiuram disulfides are used as vulcanization enhancers, fungicides, and seed treatment agents. Commercial production is still performed by means of oxidation with Cl2. Although their electrochemical synthesis avoids the production of NaCl, which is inevitable in the other processes, it is currently not being employed in industry. 

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