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Search for "LUDVÍK J.": 2 articles found.
KŘEN V., KOZOVÁ J., LUDVÍK J., KOFROŇOVÁ O., ŘEHÁČEK Z. (1988): Physiological activity of immobilized Claviceps cells producing clavine alkaloids. Česká Mykologie 42(1): 52-55 (published: 10th February, 1988)
abstract
Immobilized cells of the saprophytic Claviceps fusiformis culture can be cultivated under semicontinuous conditions for long time periods. The biocatalyst can produce alkaloids for up to 550 days with 25 cycles of the medium replacement. Specific productivity of the catalyst (average during first 100 days) is 6200 μg of alkaloids per g wet mass of the mycelium per day. Glycolytic pathway in the immobilized cells exhibited 100 times higher catabolic activity (phosphofructokinase) than gluconeogenetic activity (fructose 1,6-bisphosphatase). In immobilized cells, the final production phase was characterized by a decrease in activity of the tricarboxylic acid cycle (malate dehydrogenase and citrate synthase), similarly to suspension culture. It has been proved that during 50 days of semicontinuous cultivation the immobilized cells maintain sufficient activity of the key catabolic pathways and consequently a physiological state suitable for the production of clavine alkaloids. Morphological and ultrastructural changes were studied with scanning and transmission electron microscopy.
ČERNÝ A., LUDVÍK J., HERVERT V., BLATTNÝ C.SR. (1977): Vielfarbige Verkümmerung der Fichte und Zusammenhang dieser Erkrankung mit dem massenhaften Auftreten des Hallimasches in der Ostslowakei. Česká Mykologie 31(3): 126-131 (published: 1977)
abstract
The multicoloured dwarfing disease of spruce has been observed and studied since 1950 on Norway spruce (Picea excelsa Link) in Eastern Slovakia, in the region of the Poprad and Dunajec rivers. The mass dying of trees was primarily attributed to honey fungus [Armillariella mellea (Vahl ex Fr.) P. Karst.]. The authors present consistent differences between the common infection of spruce by this fungus and the “multicoloured dwarfing disease of spruce.” Their hypothesis that this is a viral disease was confirmed electron-microscopically by detecting isometric particles in the needles of diseased spruces. Armillariella mellea probably acts as a vector in this process and contributes to the faster death of infected trees. The transmission of the multicoloured dwarfing disease of spruce was successfully achieved by grafting using bark shields.
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