Gene duplication and loss play an important role in the evolution of novel functions and for shaping an organism's gene content. Recently, it was suggested that stress-related genes frequently are exposed to duplications and losses, while growth-related genes show selection against change in copy number. The fungal chitinase gene family constitutes an interesting case study of gene duplication ...

Fusarium graminearum (teleomorph Gibberella zeae) is a prominent pathogen that infects major cereal crops such as wheat, barley, and maize. Both sexual (ascospores) and asexual (conidia) spores are produced in F. graminearum. Since conidia are responsible for secondary infection in disease development, our objective of the present study was to reveal the molecular mechanisms underlying conidiog...

Waitea circinata var. zeae (anamorf Rhizoctonia zeae) is an important pathogen of mainly monocotyledonous plants characterized by its soil-borne nature and capability for the long-term preservation. The host range W. recently expanded to several dicotyledonous crops. latest research conducted in Serbia revealed this as causal agent root neck rot, well plant decay cabbage oilseed at localities F...

Our laboratory has been working for the last several years with bacterial strains (designated as 1B-A, 1B-C, 1B-E, and 1D-3) isolated from South Dakota wheat foliage and residue which are able to antagonize Fusarium graminearum in laboratory plate assays and in field plot trials. Although we have known for many years that the bacterial strains are endospore formers that are able to grow aerobic...

Sterols from free sterol and steryl ester fractions from Heterodera zeae and from total lipids of Zea mays roots were analyzed by gas-liquid chromatography (GLC) and by GLC-mass spectrometry. The major free sterols of H. zeae were 24-ethylcholesterol (54.4% of total free sterol), 24-ethylcholesta-5,22-dien-3beta-ol (13.3%), 24-methylcholesterol (12.5%), and cholesterol (7.2%). The same four ste...

The corn cyst nematode Heterodera zeae was detected in soil from an organic maize field in northern Greece. In greenhouse studies, reproduction of H. zeae was detected on maize plants (Zeae mays) using soil high in organic matter; the field was under winter fallow at the time of sampling. Maize plants were grown in a greenhouse with soil from the affected field used as inoculum. Females appeare...

Heterodera zeae, the corn cyst nematode, is redescribed and illustrated with comparative details and measurements of females, cysts, and larvae from Maryland, USA; and India. Scanning electron micrographs o f specimens from the United States are also presented. Revised measurements for the larval stylet and new diadnostic characters, especially in the cyst cone, for H. zeae are given. The relat...