以主动防堵的思路，提高国产 免播机质量与尺寸受限情况下的防堵 性能。先后研制出带状旋耕、条带粉 碎和驱动圆盘3种主动防堵的轻型免 播机，防堵能力强，能胜任高产玉米 地免耕播种小麦，质量316~500 kg/m， 与国产拖拉机匹配，价格为国外免播 机1/8左右。田间对比试验表明，轻型 主动防堵免播机动土量和动力消耗比国 外免播机大一些，但在小麦出苗、长势 和产量上优于国外机器。2006年推广近 2万台，玉米地免耕播种小麦约 40×104 hm2。

The first performance of the no -till seeder is to avoid the stalk blockage while seeding.  To solve the blockage problem,  oversea no-till seeders mostly rely on heavy weight (760-1130 kg/m) or big size.  But those seeders are not suitable for Chinese conditions of small land size,  small tractor and weak left force (300~600 kg/m),  and are expensive as well.  After 10 year efforts since 1990,  light passive anti-blockage no-till seeders were developed and largely applied to the middle and low yield regions.  However,  the anti-blockage performance of the seeders is limited,  difficult to work in the high yield region. From 1998,  3 types of light and active anti-blockage no-till seeders,  strip rotary hoe,  strip chopping and power driven disk no- till seeders,  have been developed.  Those seeders have strong anti-blockage ability, and can directly seed wheat on the heavy maize stalk mulching field.  The unit weight is 316~500 kg/m,  which can matchdomestic tractors. The price is 1/8 of oversea no-till seeders. From the planting quality test of 3 no-till seeders in 2004~2006,  the light active anti-blockage no-till seeders have shown more soil disturbance and power consuming than oversea no-till seeders,  but had advantages of wheat emergence,  seedling growth and wheat yield.  Nearly 20, 000 pieces of the light & high anti- blockage no-till seeders have been applied to the direct seeding wheat in maize stalk mulching field of 400, 000 hm2 in 2006,  resulted resources saving,  environment protection and farmer benefits increasing.