Abstract:

In order to resist the adverse effect of spring low temperature on wheat frozen injury, and to improve frost resistance of winter wheat, this experiment was conducted to study the effect of spring low temperature on different sowing date winter wheat frozen injury to leaves, internodes and spikes by using a randomized block design in Linfen, Shanxi Province. The results showed that the rate of freezing injury to leaves per plant increased gradually with putting off sowing date with the range from 3.0% to 55.4%. The rate of freezing injury to tillering leaves per plant was higher than that of main stem leaves with the difference of 16.6%. Association of the rate of freezing injury to leaves per plant with fresh weight per plant and green leaves per plant was higher than that with other biological characters. The freezing injury to internodes also tended to get heavier along with delaying sowing date and damage degree of the 1st internodes was slighter than that of the 2nd one. The rate of freezing injury to spikes was higher at the two ends of sowing date than that of the medium sowing date, the injury on October 22th was the lightest, on October 12th was damaged most seriously and the range was 11.58%. The reason for difference among different treatments was also analyzed in this study, and putting forward that cultivating the strong seedling before winter was one effective measure to prevent and relieve the freezing injury in spring.