Chlorothalonil applications

Plant. Degrades in plants to 4-hydroxy-2,5,6-trichloroisophthalonitrile (Hartley and Kidd, 1987), l,3-dicyano-4-hydroxy-2,5,6-trichlorobenzene, and l,3-dicarbamoyl-2,4,5,6-tetrachloro-benzene (Rouchaud et al., 1988). No evidence of degradation products were reported in apple foliage 15 d after application. The half-life of chlorothalonil was 4.1 d (Gilbert, 1976). 

Chlorinated hydrocarbons (chlordane, endosulfan, and chlorothalonil). Symptoms of exposure were dermatitis,eye irritation, nausea, and dizziness. Entry into treated areas was from 0 to 1 day after application. 

In the first test, conducted in July under hot and relatively dry conditions, the grass was cut to 5 cm and raked prior to application of the chlorpyrifos/ chlorothalonil mixture. Deposition rates were determined by strategic placement of 10-cm X 10-cm cotton gauze coupons backed with aluminum foil. The test plot was allowed to dry for 4 h before sampling. The mean transfer efficiencies for chlorpyrifos were 2.37 ng/m (0.087%) for the PUF roller and 1.05 ng/m (0.039%) for the drag sled. The transfer efficiencies were much higher for... 

Pentachloronitrobenzene (PCNB) was introduced in the 1930s and is widely used as a soil fungicide for seed treatment and foliar applications. Hex-achlorobenzene was introduced in 1945 to treat seeds and foliage. (HCB, Anti-carie, Ceku C.B., No Bunt). Chlorothalonil was introduced in 1964 it is a broad spectrum foliar or soil-applied fungicide used on many crops. Dicloran is a popular and widely used fungicide for the protection of a variety of fruits and vegetables. 

Salau, J. S., Alonso, R., Batllo, G., and Barcelo, D., Application of solid-phase disk extraction followed by gas and liquid-chromatography for the simultaneous determination of the fungicides — captan, captafol, carbendazim, chlorothalonil, ethirimol, folpet, metalaxyl, and vinclozolin in environmental waters. Anal. Chim. Acta, 293, 109-117, 1994. 

However, in 2002, when G143A-based resistance was detected in Mycosphaerdla graminicola (anamorph Septoria tritici), only DMIs and chlorothalonil-based products were available to substitute Qols. Accordingly, because of the high economic importance of Septoria tritici in European wheat production, Qol applications dropped sharply after the rapid spread of this resistance in the years 2003 and 2004. 

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