B. Moerschbacher, B. Heck, K. H. Kogel, O. Obst, and H. J. Reisener Institut für Biologie III der RWTH Aachen, Worringer Weg, D-5100 Aachen, Bundesrepublik Deutschland Z. Naturforsch. 41c, 839—844 (1986); received April 4/June 9, 1986 Triticum aestivum, Puccinia graminis f. sp. tritici, Hypersensitive Response, Lignification, Elicitor The genuine biotic elicitor from germ tube walls of Puccinia...

The biological control agent Pseudomonas fluorescens was used against the bacterial wilt causing Ralstonia solanacearum. The present investigation focuses on the role of defense related enzymes in imparting resistance in tomato against R. solanacearum. A total of ten rhizobacterial isolates were screened against R. solanacearum, of which three isolates (Pf3, Pf5 & Pf8) showed a maximum inhibiti...

Salicylic acid (SA) is an elicitor to induce the biosynthesis of secondary metabolites in plant cells. Hydrogen peroxide (H2O2) plays an important role as a key signaling molecule in response to various stimuli and is involved in the accumulation of secondary metabolites. However, the relationship between them is unclear and their synergetic functions on accumulation of secondary metabolites ar...

Buckwheat genus (Fagopyrum Mill.) is one of the aluminium tolerant taxonomic units of plants. The aim of the study was an evaluation of the aluminium (50 μM effect on phenolic accumulation in various parts of buckwheat plants (Fagopyrum esculentum Moench). Detection of increasing of total phenolic content, changes in flavonoid and anthocyanin content and phenylalanine ammonia-lyase activity (PA...

Wounding during the preparation of fresh-cut lettuce induces the synthesis of phenylalanine ammonia lyase (PAL, EC 4.3.1.5), and the synthesis and accumulation of specific phenolic compounds (e.g., chlorogenic acid) that contribute to subsequent tissue browning. Increased PAL activity and phenolic content were not induced in non-wounded lettuce that was kept in close proximity to wounded tissue...

Phenylalanine ammonia-lyase (PAL) has a crucial role in secondary phenylpropanoid metabolism and is one of the most extensively studied enzymes with respect to plant responses to biotic and abiotic stress. Here, we identified the pepper (Capsicum annuum) PAL (CaPAL1) gene, which was induced in pepper leaves by avirulent Xanthomonas campestris pv. vesicatoria (Xcv) infection. CaPAL1-silenced pep...

Stored cut lettuce gradually turns brown on the cut section after several days of storage, because cutting induces phenylalanine ammonia-lyase (PAL) activity, the biosynthesis of polyphenol is promoted, and the polyphenols are oxidized by polyphenol oxidase. Here, the effect of heat shock treatment at 50 degrees C for 90 s on the quality of cut lettuce during cold storage was examined. The heat...

The pectic enzymes produced in vitro by 8 isolates (5 Highly virulent and 3 Weakly virulent) of Fusarium oxysporum , were detected by spectrophotometry, and characterized by polyacrylamide gel electrophoresis with substrate-containing gels (zymogram). Analysis of the polygalacturonase (PG) isozyme banding patterns (zymogram) identified two distinct phenotypes among the isolates from chickpea (C...

The first enzyme of the phenylpropanoid pathway, Phe ammonia-lyase (PAL), is encoded by four genes in Arabidopsis thaliana. Whereas PAL function is well established in various plants, an insight into the functional significance of individual gene family members is lacking. We show that in the absence of clear phenotypic alterations in the Arabidopsis pal1 and pal2 single mutants and with limite...

The effects of different concentrations of copper (0–800 μmol) on growth, protein contents, peroxidase (POD), catalase (CAT), superoxide dismutase (SOD), and phenylalanine ammonia-lyase (PAL) in Jatropha curcas L. seedlings were assessed by means of pot experiments. Results suggested that increased copper concentrations lead to decreased shoot elongation and seedling biomass. Protein content in...