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Defence reactions: 02- generation, superoxide dismutase, catalase, guaiacol peroxidase and ascorbate peroxidase activities after B. cinerea infection in tomato plants propagated in vitro and grown in vivo have been compared. Infection resulted in rapid 02- generation. Superoxide dismutase activity increase was slower than 02- response. In plants propagated in vitro catalase and guaiacol peroxidase activities after infection were induced less strongly than in plants grown in vivo. K2HP04 pretreatment of plants grown in vitro enhanced significantly the activities of catalase and guaiacol peroxidase after infection. Slight restriction of B. cinerea infection development in in vitro propagated plants pretreated with K2HP04 was observed. Porównanie reakcji obronnych po infekcji Botrytis cinerea u roślin pomidora otrzymanych techniką in vitro i rozmnażanych z nasion.
The effects of soil or in vitro grown plants, pretreatment conditions, donor tissue and isolation procedure on protoplast yield from cotyledons and leaves of tomato cv. 'Perkoz' and 'Zorza' were studied. The highest protoplast yield of 1.5 x l0(7) /g FW was obtained from leaves of in vitro grown plants. Low light intensity during donor plants in vitro culture and dark pretreatment were essential for successful protoplast isolation while cold pretreatment was not. Tissue preplasmolysis prior to transfer to enzyme mixture increased 4-fold the number of isolated protoplasts. Glycine and bovine serum albumin in the isolation medium did not significantly influence the protoplast yield.
 The redox status of the cell is described by the ratio of reduced to non-reduced compounds. Redox reactions which determine the redox state are an essential feature of all living beings on Earth. However, the first life forms evolved under strongly anoxic conditions of the young Earth, and the redox status probably was based on iron and sulphur compounds. Nowadays, redox reactions in cells have developed in strict connection to molecular oxygen and its derivatives i.e. reactive oxygen species (ROS). Oxygen has started to accumulate on the Earth due to oxygenic photosynthesis. All aspects of aerobic life involve ROS, reactive nitrogen species (RNS), antioxidants and redox regulation. Many different redox-active compounds are involved in the complex of redox processes, including pyridine nucleotides, thioredoxins, glutaredoxins and other thiol/disulphide-containing proteins. Redox regulation is integrated with the redox-reactions in photosynthesis and respiration to achieve an overall energy balance and to maintain a reduced state necessary for the biosynthetic pathways that are reductive in nature. It underlies the physiological and developmental flexibility in plant response to environmental signals.
The activity of ß-1,3-glucanase and chitinase in bean plants treated with B. cinerea products or/and infected and in cell cultures after application of fungal products has been studied. Botrytis cinerea infection and culture filtrates, ethanol precipitates, glucan and conidial extract treatment markedly enhanced the activity of both hydrolases. Cell cultures treated with B. cinerea products reacted similarly to intact plants. In plants pretreated with 2-day culture filtrate and conidial extract and then infected, ß-1,3-glucanase and chitinase were induced stronger than after infection without pretreatment.
Using CM-Sepharose column chromatography it was shown that Fusarium avenaceum produced two forms of endo-polygalacturonase, one exo-polygalacturonase and two forms of endo-xylanase in infected lupin roots. A glycoprotein obtained from lupin seedlings inhibited endo-polygalacturonases, exo-polygalacturonases and xylanases but more the first ones. Two forms of endo-polygalacturonase did not differ in their sensitivity to the glycoprotein.
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