Influence of drought stress on tassel development characteristics and yield of maize

Objective  To explore the effects of drought stress on maize tassel development characteristics and yield, and provide a theoretical basis for drought resistance and yield protection of maize planting in northeast China.

Method  In the pot experiment, original soil treatment and adding soil conditioner treatment were set up. Different drought stress degrees of normal water supply (CK), light drought stress, moderate drought stress, and severe drought stress were conducted from the big trumpet stage to silking stage of maize, to study the effects of different drought stress degrees on maize anthesis-silking interval, tassel morphological and physiological characteristics and yield.

Result  Drought stress delayed the silking time of the female inflorscence of maize causing the tasseling and, silking of the maize to be asynchronous, most seriously under severe drought stress. Compared with CK, the anthesis-silking interval in the original soil and adding soil conditioner treatments was extended by 6.33 and 4.67 d, respectively. Different drought stress degrees decreased the maize size and spindle length. Light drought stress was conducive to the accumulation of dry matter in the maize tassels, and compared with CK, the tassel dry matter in the original soil treatment and the adding soil conditioner treatment increased by 5.18% and 14.87%, respectively. Drought stress prompted the tassels to secrete antioxidant system enzymes and osmotic adjustment substances to resist adversity damage. However, under severe drought stress, too much malondialdehyde (MDA) and harmful substances were produced in the tassel, which caused the activity of the antioxidant system enzyme to decrease. Drought stress caused a serious decline in maize yield. Under severe drought stress, the maize yield in the original soil treatment decreased by 62.39% compared with CK, and the yield in the adding soil conditioner treatment decreased by 57.77%.

Conclusion  Drought stress seriously affects the development and yield of maize tassels, especially under severe drought stress, which causes irreversible damage to the tassels. The application of soil conditioner can improve the stress resistance of maize tassels to a certain extent, thereby ensuring the normal growth and development of maize tassels and yield.