Abstract :
In nature plants grow close to each other, hence there must be a competition arises between them for nutrition and
space. For their survival plants must have some strategy to defense and attack. Plants produce various secondary metabolites
which may not be of nutritional values and have toxic effects. These metabolites when released out of plants and come in
contact with another plant, exerts some effects (deleterious or beneficial) on recipient plant. These metabolites are known as
allelochemicals or allelopathins. Allelochemicals also serve as defense agent against herbivores or competing plants due to
their toxic nature. They maybe used as a toolfor attack. They exert biotic stress which is called as allelochemical stress or
allelopathy. Present study investigates the adverse impact of allelopathy on recipient plant with special reference to
production of ROS, oxidative stress and defense enzyme system.
Keyword :
Allelochemicals, Allelopathy, Biotic stress, Catalase, Superoxide dismutase, Peroxidase, ROS.