关键词: 转Bt基因作物, 转Bt基因作物, 土壤动物, 生态风险, 蚯蚓, 线虫

Abstract: To clarify high-yield and high-efficient cultivation techniques for late sowing and early-maturing winter wheat new cultivar‘Hengke6021’, and to explore its combination with“Double Late- Cropping System”, the effects of sowing date and planting density on the yield and its components of this cultivar were studied. The experiment used a split plot design including 5 sowing dates and 6 planting densities. The experiment was conducted at Shenzhou Research Station (37°44′N, 115°42′E) in Hebei Province during 2014- 2015. The results showed that: (1) the sowing date affected the spike number per unit area, 1000-kernel weight and grain yield significantly, but did not affect the kernels per spike obviously, late sowing increased spike number, which was the base for high yield, and was suitable for“Double Late-Cropping System”, the planting density affected both grain yield and its components significantly; (2) the yield increased first, and then decreased along with the sowing date’s delaying, and increased with the planting density’s increase, the spike number per unit area increased along with sowing date’s delaying and planting density’s increase, the kernels per spike had no significant differences at different sowing dates, but it decreased with planting density’s increase, the 1000- kernel weight decreased along with sowing date’s delaying and planting density’s increase. Under one irrigation in spring, the suitable sowing date of‘Hengke6021’was October 12-25th, the best sowing date of‘Hengke6021’was October 17-21th, and the planting densities were 3.3×106-3.9×106/hm2. Combining with“Double Late-Cropping System”, the whole-year yield could reach 20221.85 g/hm2.