Abstract:

To study the influence of sowing date and variety on the yield of direct seeding rice and provide a basis for the selection of the sowing period and varieties, eight hybrid rice varieties mainly promoted in the production were used as test materials, three sowing dates were set up in the three ecological areas of Chongqing, and the yield, effective ear and solid grain characteristics of each type of rice varieties were studied. Yield and its components were compared to analyze the relationship between the yield and sowing dates. The results showed that there were significant differences in the average yield during different sowing periods and varieties (P<0.05). The rice yield of No.2 (8931.96 kg/hm²) sowing date in Xiushan was significantly higher than No. 3 sowing date (7801.83 kg/hm²). The yield of No.2 sowing date (9490.06 kg/hm²) in Wanzhou was significantly higher than that in No.1 (9113.79 kg/hm²) and No.3 (8783.78 kg/hm²). The yield of two-line hybrid rice was significantly higher than that of three-line hybrid rice, mainly because of higher number of effective panicles. In Wanzhou and Xiushan experimental sites, the differences of yield among varieties were significant. Production performance of ‘C liangyou huazhan' was outstanding. On average, the sowing date in the west of Chongqing should be in early April, the northeast of Chongqing should be in the middle of April, and the southeast of Chongqing should be in late April, which is conducive to stable yield.

Key words: rice, direct seeding, seeding date, yield, yield components