0000000000591342
AUTHOR
Dace Kruzmane
Effect of regurgitant from Leptinotarsa decemlineata on wound responses in Solanum tuberosum and Phaseolus vulgaris.
The effect of regurgitant from Leptinotarsa decemlineata Say larvae on wound-induced responses was studied using two plant species, Solanum tuberosum L. and Phaseolus vulgaris L. Wounding of one leaf of intact S. tuberosum plants differentially affected ethylene production and activities of peroxidase and polyphenol oxidase. Only polyphenol oxidase activity was stimulated by wounding in both wounded and systemic leaves. Peroxidase activity was not affected by wounding. Wounding caused only a transient increase of ethylene production from wounded leaves. The application of regurgitant to wound surfaces stimulated ethylene production as well as activities of peroxidase and polyphenol oxidase …
Characterization of 1-aminocyclopropane-1-carboxylic acid oxidase from barley (Hordeum vulgare L.) seedlings and pine (Pinus sylvestris L.) needles
Abstract Biochemical characteristics of 1-aminocyclopropane-1-carboxylic acid (ACC) oxidase extracted from barley ( Hordeum vulgare L.) leaves and pine ( Pinus sylvestris L.) needles were investigated. ACC oxidase from barley leaves was soluble while for complete recovery of ACC oxidase from pine needles addition of Triton X-100 to extraction medium was necessary. The enzyme required Fe 2+ , ascorbate and NaHCO 3 for maximum activity. A non-linear time course of ACC oxidase reaction indicated possible catalytic inactivation of the enzyme. The maximum activity was measured at pH 7.0–7.2 for ACC oxidase from both barley leaves and pine needles. The apparent K m for ACC was found to be 77 and …
Effect of CCC and pH on shoot elongation in Sedum rubrotinctum R.T. Clausen
Sedum rubrotinctum plants grown during winter in a glasshouse had decreased leaf density and increased internode length as well as loss of red coloring, leading to diminished ornamental value. Treatment with growth retardant (2-chloroethyl)trimethyl ammonium chloride (CCC) reduced internode length as well as the number of internodes. Concomitant changes of ethylene production and peroxidase activity were found in CCC-treated plants. Substrate pH had a significant effect on the growth of S. rubrotinctum. This leads to the conclusion that increase of shoot growth during winter period could be reversed by means of growth retardant CCC and acidification of substrate.
Modulation of Solanum tuberosum L. morphogenesis and antioxidative status in a stem explant culture by limitation of gas exchange: Putative effects of ethylene
Summary The main objective of the present study was to test the hypothesis that increased concentrations of ethylene under conditions of limited gas exchange during in vitro cultivation of potato ( Solanum tuberosum L.) stem explants may lead to increased capaciry of antioxidative defense. By varying the tightness of closure and application of inhibitors of ethylene biosynthesis it was possible to accumulate various concentrations of ethylene in the internal atmosphere of culture flasks, which depended on excision-stress induced ethylene biosynthesis. In tightly closed cultures inhibition of linear growth, promotion of radial expansion and development of an apical hook occurred. Treatment w…