[Effects of small amount precision seeding on winter wheat yield].

A two-year autumn seeding experiment was conducted during 2001-2003 in Beijing to study the effects of small amount precision seeding on winter wheat yield. When the seeding amount was 22.5 kg x hm(-2), the best average yield of winter wheat varieties DS No.1 and Linkang No.1 was 6836.25 and 7353.75 kg x hm(-2), respectively, and some experimental plots had a yield surpassed 7500 kg x hm(-2). The test varieties had a normal expression of growth and development in their growth period, and the contents of total saccharide, proline and lysine in seedlings were higher, and the tillering ability of plant was stronger than the control. The net photosynthesis and transpiration rates, RS, COND and CINT of flag leaf showed the vigorous physiological functions of the plants, and the higher activities of nitrate reductase and SOD showed their stronger metabolism activity. There were more spikes per plant for the test varieties. In practicing small amount precision seeding, variety selection is the prerequisite, and sowing amount is the heart of the matter.