Antioxidant response of maize, under drought stress, to foliar applied (2-chloroethyI) trimethylammonium chloride (Chlormequat)

摘要

This field experiment was to study the effect of the plant growth regulator, chlormequat on the physiological characteristics of densely planted maize and its subsequent effect on maize yield under drought conditions. A randomized complete block design utilizing spilt plots, with four replications was used. Irrigation stopped at the beginning of seed filling (after pollination) in half the main plots and the other half continued to receive irrigation normally. Two separate applications of Chlormequatat 1.5 L ha'1 were made, at either the 6 to 8 leaf crop stage or 15 days later, on separate spilt plots. Some plots did not receive a chlormequat treatment. The following characteristics were studied: seed yield, 1000 seed weight, total dry matter weight, leaf cell membrane leakage and antioxidant enzymes activity (superoxide dismutase, catalase and glutathione peroxidase). Drought stress decreased seed yield but spraying chlormequat increased seed yield significantly. Chlormequat treatment increased 1000 seed weight, total dry matter weight and antioxidant enzyme activity.