Effect of phytoplasma infection on metabolite content and antioxidant enzyme activity in lime (Citrus aurantifolia)

Abstract

The objective of the present work was to study biochemical alterations in lime plants infected by the Candidatus Phytoplasma aurantifoliae. Changes in antioxidant activities, content of chlorophylls (Chl), carotenoids (Car), soluble proteins, sugars and auxin (IAA) in infected plant were investigated. The activities of polyphenol oxidase (PPO), peroxidase (POX) and superoxide dismutase (SOD) were observed to be greater in infected leaves than the healthy control. Also according to nondenaturing PAGE, in infected leaves all the antioxidative enzymes isoforms were stronger than that of the healthy control. These results suggest that antioxidant enzymes can be activated in response to infection by phytoplasma. The decrease in content of proteins, total soluble and reducing sugars in infected plants point out changes in host metabolism due to the phytoplasma infection. The reduction in chlorophylls and auxin content shows that the phytoplasma can interfere in photosynthesis and induces senescence in the leaf. In conclusion, this study provides new insights into the lime response to phytoplasma infection.

Biochemical changes in the leaves of mungbean (Vigna radiata) plants infected by phytoplasma

“…Thus, various antioxidant enzymes such as peroxidase (POD), superoxide dismutase (SOD), catalase (CAT) and polyphenol oxidase (PPO) participate in ROS metabolism during the pathogen attack. High expression of these defence enzymes makes the plant resistant to pathogen invasion [3,4]. However, these mechanisms fail when the plant is infected by a virulent pathogen.…”

Antioxidative Capacity and Electrolyte Leakage in Healthy Versus Phytoplasma Infected Tissues of Euphorbia coerulescens and Orbea gigantea

“…Previous reports demonstrated that POX and PPO may participate in the responding defense reaction by inducing plant resistance against pathogenic agents [31]. An increase in PPO activity in phytoplasma infected Citrus auarntifolia has been reported [9]. A significant increase in GR activity was observed in PI tissues of O. gigantea (Figure 2E) but no significant difference in APX activity in PI tissue of O. gigantea compared to healthy tissue.…”

“…Various antioxidant enzymes such as superoxide dismutase (SOD), peroxidase (POX), polyphenol oxidase (PPO), catalase (CAT), ascorbate peroxidase (APX) and glutathione reductase (GR) participate in ROS metabolism during the pathogen attack. The development of an antioxidant defense system in plants can protect them against oxidative stress damage by the scavenging of ROS [8,9].…”

Detection of Root (Wilt) Disease of Coconut (Cocos nucifera L.) based on polyacrylamide gel electrophoresis

“…These proteins might have been up regulated in the plant in response to phytoplasma infection. Citrus aurantifolia plants infected with phytoplasma showed decreased intensity of some protein bands and exhibited two additional bands of 15 and 26 K Da in the SDS PAGE pattern of infected leaves as compared to that of the healthy plants (Zafari et al, 2012). The method, described in this study, requires preliminary standardization using disease middle adult sample palms for optimizing the amount of protein in sample extract to be loaded to gel, to obtain intensities of discriminating bands (B4 to B7 in WCT, B4-B5 in CGD and B5-B6 in MGD) equal to that given in the figures (1to 3) and for giving similar scores for band intensities as illustrated in the Tables (1 -3) corresponding to the band intensities observed in the three gels of the cultivars in the present study.…”