Abstract:

To study the effects of drought stress on plant height, ear characteristics and yield of the same maize variety at different growth stages, a comparative experiment was set up with six treatments, including sufficient water supply during the whole growth period, the natural drought, the water control at the jointing stage, the water control at the tasseling stage, the water control and re-watering at the jointing stage and the water control and re-watering at the tasseling stage. The differences of the maize height, ear characteristics and yield under different treatments were compared. The results showed that the drought stress shortened the maize plant, decreased the ear length by 7.88%-54.55%, decreased the ear diameter by 14.58%-52.08%, increased the barren ear tip length by 66.67%-258.33%, decreased the 100-kernel weight by 0.99%-41.36%, and decreased the yield per plant by 15.03%-94.41%, which eventually led to a yield reduction of 23.57%-90.03%. The effects of drought stress on yield were significantly different at different growth stages. The effect of the drought stress during the whole growth period was the most serious, with almost no yield, followed by that at the jointing stage. The effect of the drought stress at the tasseling stage was the least. After re-watering, the biomass reduced by the previous drought stress was partially compensated, so the ear characteristics and 100-kernel weight were all improved, and the yield reduction was reduced.

Key words: maize, drought stress, re-watering, ear characteristics, yield