Showing 3 results for Peroxidase
A. Alami, M. Taeb, A. Lotfi, Y. Sadeghian Motahar,
Volume 7, Issue 1 (4-2003)
Abstract
Thirty genotypes of pistachio cultivars and related species were evaluated for genetic diversity using three polymorphic isozymes, i.e. Esterase, Peroxidase and Malate dehydrogenase. Young leaves of pistachio were crushed with extraction buffer containing: 20% sucrose, 0.01 M dithiothretiol, 2% polyethylene glycol, and 8% polyvenyl polypyrollidone. Samples were analyzed using isoelectric focussing on polyacrylamide gels containing 2% (W/V) ampholyte. All the three isozymes revealed high degrees of polymorphism in pistachio cultivars and related species. Maximum polymorphism was observed for Est. enzyme. A total of 19 bands in Est. and 28 bands in MDH were observed in a wide range of pH gradient however, in Per. there were 11 bands all of which located in a narrow range of pH gradient. Cluster analysis based on the three system enzymes revealed that all the 30 pistachio genotypes were in 8 main classes and 20 subclasses and the extent of genetic similarity reduced from cultivated varieties to species, which were finally classified in 3 groups. Sarakhs variety, a wild type of P. vera, was classified in a group between cultivated varieties and species.
A.h. Jamali Zavareh, A. Sharifi Tehrani, M. Mohammadi,
Volume 11, Issue 41 (10-2007)
Abstract
One of the properties of systemically acquired resistance in plants is their concomitance with the biochemical changes including enhancement of activities of defense-related enzymes. The leaf extract of Reynoutria sachalinensis (F. Schmidt) Nakai is known to be an effective compound for the control of a few plant diseases particularly powdery mildew of cucurbits (caused by fungal pathogen Podosphaera fusca), by inducing host defense responses. In the present investigation, the effects of this extract on some defense responses of cucumber plants were studied via in vivo tests. Changes of defense responses in the extract treated-cucumber plants, with or without pathogen inoculation, were studied and compared with those of non-treated control plants. Results indicated that specific activity of peroxidase increased significantly in treated tissues. Enhancement of enzyme activity showed the same patterns in both the pathogen inoculated- and non-inoculated-plants thus the pathogen attack did not affect the enzyme activity. Specific activity of phenylalanine ammonia-lyase in the non-inoculated extract treated-plants showed a transient fast increase during 24 hours after the treatment, whereas in the inoculated ones, it showed a permanent slow increase probably due to the interaction between extract treatment and pathogen attack. Phenolic content of extract treated-plant tissues, despite small fluctuations, did not show any definite pattern of changes.
Amir Hossein Khoshgoftarmanesh, Hamid Reza Eshghizadeh, Azadeh Sanaeei Stovar, M. S. Mirlohi, M. Taban,
Volume 17, Issue 64 (9-2013)
Abstract
Iron chlorosis is an important disorder of plane trees (Plantanus orintalis L.) in green space of Isfahan city. Before using reclamation methods for correcting Fe chlorosis, it is necessary to find a suitable index for evaluating plant Fe status. Therefore, activity of glutathione peroxidase (GP) enzyme and concentration of carotenoids and chlorophyll a and b pigments, as physiological indices of active Fe, were compared to total Fe concentration in leaves to evaluate Fe status in plane trees. For this purpose, severity of chlorosis of plane trees at different regions of Isfahan city was recorded. Then, 73 trees with different severity of chlorosis symptoms were selected and their leaves were sampled on July 2009 and 2010. Concentration of Fe, chlorophyll a and b and carotenoids in leaves as well as activity of GP enzyme were measured. Results showed large variation in leaf Fe concentration between young and old leaves and also between leaves with different chlorosis severity symptoms. No correlation was found between leaf Fe chlorophyll concentration and severity of chlorosis symptoms. Also, concentrations of chlorophyll a in young and old leaves with very severe chlorosis symptoms were 44 and 37% smaller than that in young and old leaves with slight chlorosis symptoms, respectively. Concentration of chlorophyll b in young and old leaves with very severe chlorosis symptoms were 40 and 37% smaller than that in young and old leaves with slight chlorosis symptoms, respectively. Concentration of carotenoids varied among young and old leaves with different severity of chlorosis symptoms. Activity of GP in young leaves was also reduced by intensifying severity of chlorosis symptoms. According to the result of the present study, activity of GP enzyme and leaf concentration of carotenoids and chlorophyll a, as suitable physiological indices of active Fe, had close correlation with severity of Fe chlorosis in plane trees. Also, deficiency of active Fe in leaves is a probable reason of chlorosis symptoms in plane trees.
