Thesis (Ph. D.)--University of Wisconsin--Madison, 1930. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 52-53).

Hohenheim, Univ., Diss., 2001.

Thesis (M.Sc.(Chemistry))--University of Pretoria, 2001. / Includes abstracts in English and Afrikaans. Includes bibliographical references.

Techn. Hochsch., Diss., 2002--Aachen.

University, Diss., 2003--Münster (Westfalen).

Universiẗat, Diss., 2003--Kiel.

FHB caused by phytopathogenic fungi of the genus Fusarium, one of the world's most serious diseases of agricultural crops. Fusaria are major producers of mycotoxins side. We compared methods of cereals against fungi Fusarium year in conventional and organic farming and evaluate the effectiveness of selected compounds on the growth of mycelium F. culmorum and F. poae, occurring most often in the spring malting barley. In vitro, the cultures of the isolates Fusarium the effect of preparations Zinran and Dolosul for organic farming and active substance of fungicides Zantara, Hutton and Prosaro 250 EC for conventional agriculture on mycelial growth. High efficiency at suppressing the growth of the mycelium was observed when using a fungicidal composition Zantara head blight in both species. Low efficiency in suppressing the growth of mycelium head blight was observed in the preparation Dolosul, which is approved for application in organic agriculture. Fungicidal products used in conventional agriculture are more desired efficacy against fungi Fusarium year than products used in organic agriculture.

No description available.

Foot rot disease of wheat is caused by the pathogens Fusarium cuImorum, F.avenaceum and Microdochium nivale. Symptoms of foot rot are a general browning of the stem base and leaf sheath. There is a discrepancy between the ability of fungicides to control these pathogens in vivo and in vitro, and no relationship between disease symptom severity and yield loss has been established in wheat. The identification of the causal agents of foot rot disease is not possible from examination of disease symptoms alone. This work showed that the azole fungicides flusilazole and prochloraz inhibited the germination of conidia and mycelial growth of F. culmonon, F. avenaceum and M. nivale in vitro to a varying extent. However, no consistent control of these pathogens in wheat was observed in the field using the same fungicides. Further studies employing a semicontrolled outdoor experiment showed a relationship between density and timing of inoculum application, disease symptom severity and yield loss in wheat artificially inoculated with F. culmorum and M. nivale. Molecular marker systems were used to address the problem of pathogen detection and identification. A Random Amplified Polymorphic DNA (RAPD) assay was developed to differentiate F.culmorum, F.avenaceum and two types of M.nivale (M.nivale var.nivale and M. nivale var .majus) in vitro. Selected RAPD products were cloned and sequenced and species specific primers constructed from this sequence infonnation. These primers were used in the polymerase chain reaction (peR) and were shown to detect the pathogens in host tissue. This technique was adapted by addition of a competitor fragment to the peR reaction resulting in a quantifiable competitive peR assay. Using this method the fungal biomass of each pathogen present in the host tissue could be estimated. The development of these techniques for the identification, detection and quantification of F. cuimorum, F.avenaceum, M.nivale var.nivale and M.nivale var.majus in plant tissue will allow more extensive studies of the epidemiology of these species, the competition between species and the effect of fungicides on these pathogens can be carried out.

No description available.