Changes of superoxidedismutase and peroxidase activities in pea roots infested by Heterodera goettingiana
AbstractThere are many reports about oxidative enzyme activities in the regulation of metabolic pathways in diseased and injured plant tissue (Frie, 1976), and it is known that plant tissues infected by different pathogens exhibit changes in peroxidase (EC 126.96.36.199). Increased peroxidase activity in various host-parasite interactions was associated with resistance to the disease in the host (Ferhmann and Dimond, 1967; Jennings et al., 1969; Bates and Chant, 1970, Hussey and Krusberg, 1970; Simons and Ross, 1971; Huang et al., 1971; Benedict, 1972; Rathmell and Sequeira, 1980). Lovrekovich et al. (1967) reported resistance to wild fire disease induced by infiltrating heat killed cells of Pseudomonas tabaci into tobacco leaves, and observed that this was accompanied by a marked increase in peroxidase activity. Increase of peroxidase activity and systemic resistance ,were also observed in the upper leaves of tobacco plants inoculated with tobacco mosaic virus on the lower leaves (Simons and Ross, 1970). Although peroxidase is known to be involved in disease reactions, its role is far from being conclusive and remains undefined. Recently the hypothesis was advanced of a biological mechanism of defence in plants dependent on development of cyanide resistant respiration (Arrigoni, 1979), in which the enzymes peroxidase and superoxidedismutase (SOD; E.C. 188.8.131.52) have well defined metabolic functions (Zacheo et al., 1980). As the increase in respiration (Uritani and Akazawa, 1959; Millerd and Scott, 1962; Farkas et al., 1964; Antonelli and Daly, 1966; Daly, 1976; Brenneman and Black, 1979) and the enhanced peroxidase activity has been reported during infection processes in plants, this study was undertaken to establish whether there are also changes in SOD and in which way the activity of the enzymes is correlated during the invasion of pea (Pisum sativum L.) roots by the pea cyst nematode, Heterodera goettingiana Wollenweber.