Abstract:
Water deficit is a common problem and this affect plants' physiological function and
lead to the reduction of crop production. Plants develop various reactions to
overcome this problem especially by producing antioxidants. A study was conducted
to determine the effects of water deficit on the activities of antioxidative enzymes;
catalase (CAT), peroxidase (POD) and ascorbate peroxidase (APX) in maize. Seven
days old maize plants were treated with different volume of water (0ml, 20ml, 40ml,
60ml, 80ml and 100ml). The treatment was conducted for 11 days and antioxidative
enzyme assays were carried out at 0, 1, 2, 3, 5, 7 and 11 days of treatment. The
results showed that, under water deficit, the activities of APX and CAT in leaves
increased while for POD, the activities increased at early stages but declined at the
later stages of the experiment. It can be concluded that the major reactive oxygen
species (ROS) scavenging enzyme is APX and CAT. Despite this fact, all the three
enzymes actually coordinated with each other in maintaining the balance between
useful and harmful ROS and co-regulated in overcoming stress condition.
