Abstract:
Plants can produce a number of antioxidants to protect itself against environmental stress
that effect their growth and productivity. The antioxidants that have been produced
include enzymatic antioxidants and non enzymatic antioxidants. The effects of different
volumes of water (excess water) on the ascorbate peroxidase (APx), catalase (CAT), and
guaiacol peroxidase (POD) specific activities were studied in Zea mays. Zea mays were
treated with 100, 120, 140, 160, 180 and 200ml of water for 7 days. The specific
activities of these anti oxidative enzymes were detected every 0, 1, 2, 3, 5 and 7 days of
treatment period. Water treatment significantly induced the APx and POD specific
activities especially at later stages of treatment period. Increases the volume of water led
to great increased of APx and POD specific activity. However, CAT specific activities
were not affected at earlier stage of treatment while reduced at the later stages. These
results suggest that the treatment of excess water stimulates oxidative stress in Zea mays
by inducing the APx and POD antioxidative specific activities and reduced in CAT
specific activities. As a C4 plant or plant that uses C4 photosynthesis, maize is a
considerably more water-efficient crop than C3 plants. The antioxidant metabolism has
been shown to be important in determining the ability of Zea mays to survive under
conditions of excess water stress and the up regulation of these enzymes would help to
reduce the build up of reactive oxygen species.
