Immunocompromisation of wheat host by the development of carbonylation during fusarium oxysporum infection

Abstract

Plants are continuously exposed to various kind of abiotic and biotic stress causing agents. In the present study, wheat (Triticum aestivum) was taken as a model plant to investigate the carbonylation induced immunocompromisation of wheat host during Fusarium oxysporum infection. The morphological attributes were observed to be decreased in the seedlings infected with F. oxysporum. An enhanced level of ROS, such as O2 -, and H2O2, was observed in Fusarium-infected tissues as compared to control tissues. Interestingly, stressed plants showed increased activity of antioxidant enzymes such as SOD, CAT, APX, GPX, PPO, POD, GST, and GSH-Px. The content of reduced glutathione (RGSH), total glutathione (TGSH), GSH/GSSG ratio, and ascorbate (ASC) were decreased in the seedlings exposed to Fusarium infection. The tissues were disintegrated more in the Fusarium-infected shoot than in the control shoot, due to mycelial proliferation. A higher malondialdehyde (MDA) and carbonyl (CO) content resulted from lipid peroxidation and protein oxidation, respectively, in Fusarium infected seedlings as compared to control seedlings, showing high susceptibility and indicating cellular damage and cell death. The Fusarium induced stress proteins (FISP) provide defense response against Fusarium infection. Thus, the oxidative stress triggered carbonylation is suggestive of offering susceptibility against Fusarium-induced oxidative stress and damages target proteins with irreversible modification and permanent damage, which ultimately disturb the cellular redox equilibrium in wheat. newline newline