ALLELOPATHIC EFFECT OF Β-Cembrenediol AND ITS MODE OF ACTION: INDUCED OXIDATIVE STRESS IN LETTUCE SEEDLINGS

Abstract

β-cembrenediol((1S,2E,4R,6R,7E,11E)-2,7,11-cembratriene-4,6-diol), shown to be one of the most important allelochemicals of tobacco in our previous studies, effectively inhibited the root and shoot elongation of receptor plants in a concentration-dependent manner. However, its mechanism of action remains unclear. Seedlings of lettuce (Lactuca sativa) were now treated with β-cembrenediol to clarify its mode of action. Results showed that β-cembrenediol significantly inhibited the seeding growth and reduced fresh weight of L. saiva. The compounds effectively arrested cell division and caused cell death. Exposure to β-cembrenediol induced overproduction of reactive oxygen species. Moreover, increased levels of malondialdehyde, proline and hydrogen peroxide, and decreased in chlorophyll content indicated lipid peroxidation and induction of oxidative stress. These results suggested that β-cembrenediol caused oxidative damage through enhanced generation of ROS, as indicated by increased lipid peroxidation, disruption of membrane integrity and impacted mitosis, ultimately resulted in growth inhibition of the receptor plant.

Allelochemical Activity of Eugenol-Derived Coumarins on Lactuca sativa L.

“…They observed a concentration-dependent increase in lipid peroxidation and SOD, CAT, and APX enzymatic activity and correlated the increase of these parameters to strong oxidative stress caused by the extract. Lactuca sativa also exhibited an increase in lipid peroxidation and/or activity of one or more antioxidant enzymes when under oxidative stress [23,34,[45][46][47].…”

Autotoxins in continuous tobacco cropping soils and their management

“…The root exudates of tobacco contain various secondary compounds, and some are capable of accumulating around the rhizosphere and causing autotoxicity ( Walker et al., 2003 ; Xie et al., 2007 ). β-Cembrenediol is considered as an essential autotoxin in the root metabolites of tobacco, which affects plant mitosis, enhances the generation of reactive oxygen and induces oxidative damage, increases the degree of lipid peroxidation of membranes, inhibits root and stem elongation, reduces the content of chlorophyll, and causes cell death ( Ren et al., 2017 ). Substances such as din-butyl phthalate (DBP) and diisobutyl phthalate (DIBP) have been confirmed to be major autotoxins.…”