Many studies exist about the selection phase of fungicide resistance evolution, where a resistant strain is present in a pathogen population and is differentially selected for by the application of fungicides. The emergence phase of the evolution of fungicide resistance--where the resistant strain is not present in the population and has to arise through mutation and subsequently invade the pop...

One robust result from many small-scale experiments has been that plant community productivity often increases with increasing plant diversity. Most frequently, resource-based or competitive interactions are thought to drive this positive diversity-productivity relationship. Here, we ask whether suppression of plant productivity by soil fungal pathogens might also drive a positive diversity-pro...

Fungicide mixtures produced by the agrochemical industry often contain low-risk fungicides, to which fungal pathogens are fully sensitive, together with high-risk fungicides known to be prone to fungicide resistance. Can these mixtures provide adequate disease control while minimizing the risk for the development of resistance? We present a population dynamics model to address this question. We...

In three field trials fungicides used for stem rust (Puccinia graminis) control were evaluated to assess the effect on levels of blind seed disease, seed germination and endophyte (Neotyphodium lolii) transmission. Blind seed disease infection was reduced from 24% to 5% in one of the three trials undertaken and germination was increased by between 17 and 23% in two trials. There was a negative ...

Fungal Lipids, Ergosterol, Inhibition, Etaconazole, Fungicide The triazole fungicide etaconazole (C G A 64 251) interferes with the ergosterol biosynthesis in Ustilago maydis by inhibiting the C-14 demethylation o f the sterol nucleus. During the late log growth phase o f U. maydis a novel endogenous sterol metabolite (14x-methyl-ergosta-8,24(28)dien-3/?,6a-diol) was discovered and analyzed, wh...

Environ.Entomol.13: 1010-1014 (1984) ABSTRACT Field experiments were carried out to determine if a copper-based fungicide known to deter feeding by the Colorado potato beetle, Leptinotarsa decemlineata (Say), in the laboratory, could suppress the growth of L. decemlineata populations in the field when used regularly for plant disease protection on tomatoes, potatoes, and eggplants. Larval densi...

The nematicidal activity of the fungicide ethazole was studied under greenhouse conditions in which a nematode-infested, Norfolk sandy loam was planted to cotton (var. = 'Rowden'). At planting time, the fungicide was incorporated in the soil at rates of 0-100 mg/kg soil. When assayed 4 weeks after planting, plant-parasitic nematodes in soil and roots occurred in decreasing numbers with increasi...

A new, simple, and rapid spectrophotometric method for the microdetermination of dithianon, on the basis of its reaction with a dithiocarbamate, is described. The red color, which develops instantaneously when mixing the fungicide with the reagent in acetonitrile, is stable for at least 1 h and is measured at 520 nm. Beer's law is applicable up to 12 micrograms/mL dithianon concentration. The m...

Scientific certainty regarding environmental toxin-related etiologies of breast cancer, particularly among women with genetic polymorphisms in estrogen metabolizing enzymes, is lacking. Fungicides have been recognized for their carcinogenic potential, yet there is a paucity of epidemiological studies examining the health risks of these agents. The association between agricultural fungicide expo...

By Zahi Kanaan-Atallah, Ph.D. Washington State University May 2003 Chair: Dennis A. Johnson Sclerotinia sclerotiorum (Lib.) de Bary is a cosmopolitan, homothallic and necrotrophic ascomycetous fungus dispersed by airborne ascospores and soilborne sclerotia. It causes disease in over 400 host species. A significant correlation between potato yield losses and stem rot incidence has not been obser...