Grey leaf spot is a serious yield-reducing disease of maize (Zea mays) in many parts of the world where this crop is cultivated. The causal organism associated with the disease is Cercospora zeae-maydis. Two potential sibling species have been recognized as Groups I and II. The DNA sequences for the internal transcribed spacers (ITS1 & ITS2), the 5.8S rRNA gene, elongation factor 1-alpha, histo...

The biotrophic pathogen Ustilago maydis causes smut disease on maize (Zea mays) and induces the formation of tumours all aerial parts plant. Unlike in other interactions, no gene-for-gene interactions have been identified maize–U. pathosystem. Thus, resistance to U. is considered a polygenic, quantitative trait. Here, we study molecular mechanisms (QDR) maize, how interferes with its components...

Late wilt of maize, caused by the vascular and soilborne pathogen Cephalosporium maydis, was identified in the Iberian Peninsula in 2008. During the last years the incidence and economical impact of the disease has importantly increased both in Portugal and Spain. Varieties of maize displaying tolerance to the pathogen are available, but the effectiveness can be dependent on the virulence of th...

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...

Monoxenic cultures of Heterodera zeae, the corn cyst nematode (CCN), were established on root explants of corn Zea mays L., cv. Kenworthy. The life cycle of H. zeae was determined from light anti scanning electron microscopic observations of the root explants grown in the dark at 29.5 +/- .5 C under gnotobiotic conditions. The life cycle, from the time the explants were inoculated with second-s...

The phytopathogenic fungus Ustilago maydis undergoes a dimorphic transition in response to mating pheromone, host, and environmental cues. On a solid medium deficient in ammonium (SLAD [0.17% yeast nitrogen base without ammonium sulfate or amino acids, 2% dextrose, 50 μM ammonium sulfate]), U. maydis produces a filamentous colony morphology, while in liquid SLAD, the cells do not form filaments...

The molecular mechanisms regulating the accuracy of gene expression are still not fully understood. Among these mechanisms, Nonsense-mediated Decay (NMD) is a quality control process that detects post-transcriptionally abnormal transcripts and leads them to degradation. The UPF1 protein lays at the heart of NMD as shown by several structural and functional features reported for this factor main...