Abstract:Two high yield varieties (Jilin 20 and Changnong 4) which were being popularized in Jilin province at Present were used in this experiment, Thirty treatments of simulant hail test, were made once at the stage of cotyledon; opposite leaves, first and second compound leaf. The dates of flowering and maturity were recorded, and the yields were determined in full maturity. Results of experiment showed that there were significant difference in yields between the treatments and control. The yields of fourteen treatments (No. 5, 7, 9, 12, 14, 16, 17, 20, 21, 24, 25, 28, 29, 30) were decreased significantly compared with control for two varieties in two years. The range of reductiort was 54.4-11.6 percent. The yields of treatment 10 and 18 were increased significantly compared with control ranged as 11.8-13.0 percent and yield of treatment 3 decreased in first year, but increased in second year. It showed that the yield of treatment 3 can be influenced by the environment easily. Treatment 26 increased in yield for Jilin 20 only and the average rate of inerease was about 10 percent. Five treatments (No. 1, 6, 15, 19, 22) were similar to the control in two years. Otherwise the yields of five treatments (No, 2, 4, 11; 13, 23) were decreased unsignificantly compared with control for Changnong 4, but decreased significantly for Jilin 20. Treatment 8 and 27 were unsignificant compared with control for Jilin 20, but decreased significantly for Changnong 4.
The maturity of most treatments were late than control based on the data of maturity time. Treatment 14, 207 21, 29, 30 were. late about 10 days, and No. 11, 12, 13, 18, 19, 26, 27, 28 about 3-8 days. Other treatments were different unsignficantly compared with control in maturity time, but yet trended towards late-maturing.
