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The article discusses a study on Humulus lupulus with Phoma exigua in the commercial fields of Slovenia. In a research conducted in August 2005, Humulus lupulus was found with necrotic lesions, small circular spots that developed into oval, greyish white lesions. Based on the morphological characters of the symptoms, the pathogen was identified as Phoma exigua. This observation was confirmed through the sequences of the ITS region, 5.8srDNA and ITS 2 of two isolates which were identical to Phomaexigua ITS sequences.

An abstract of the article "First Report of Hop stunt viroid Infecting Hop in Slovenia," S. Radisek is presented.

Male specific DNA sequences were selected from a Diversity Arrays Technology (DArT) mapping study to evaluate their suitability for determination of the sex phenotype among young seedlings in a hop (Humulus lupulus L.) breeding program. Ten male specific DArT markers showed complete linkage with male sex phenotype in three crossing families. Following optimization, four were successfully converted into PCR markers and a multiplex PCR approach for their use was developed. Among 197 plants (97 from the world collection; 100 from three segregating families), 94-100% positive correlation with sex phenotypic data was achieved for the single PCR amplification, whereas the multiplex approach showed 100% correlation. To develop a fast and low-cost method, crude sample multiplex PCR was evaluated in 253 progenies from 14 segregating populations without losing accuracy. The study describes, for the first time, the routine application of molecular markers linked to male sex in an intensive Slovenian hop breeding program. The methods described could be employed for screening of sex at the seedling stage in other hop programs worldwide, thereby saving resources for desirable female plants.