Studies On Rice Two Stages Seedling-Raising And High Yield Cultivation Technique In Cold Region

The studies on pattern of seedling raising, sowing time, sowing amount, varieties selection,density, fertilizer amount and phonological phase was conducted from 2005 to 2006 for the twostages seedling-raising and high yield cultivation technique.1. Compared to conventional seedling raising, the two stages seedling-raising could significantlyimprove seedling quality and the plant height, leaf age, stem thickness, tiller ratio and biomass weregreatly higher than conventional seedling-raising. The better seedling quality established principle forhigh yield.2. The best sowing time for the two stages seedling raising was from 15 March to 20 march, whichgot the highest yield and reached to 8899.0-9252.0kg/hm~2.3. The sowing amount of the two stages seedling-raising should be controlled from 400-500 g/m~2,which both increased yield and decreased the nurture area. The yield reached to 8413.4-8442.1kg/hm~2.4. One more leaf rice variety should be selected compared to conventional variety selection, whichthe effective accumulated temperature was 100-150℃higher. For example, later ripening varietyDongnong no.423 could elaborate its high yield potential, therefore reached higher yield.5. The transplanting density of two stages seedling raising should be sparser than conventionaltransplanting. The size should be ranged from 30.0*16.5cm to 30.0*19.9cm, or 20.2 to 16.8 hills/m~2(conventional transplanting was 25hills/m~2), and 2 plants/hill, which increased yield 5.4-7.9 percent.6.The fertilizer amount of two stages seedling-raising was 227.5kg/hm~2 (conventional192.5kg/hm~2), which was higher than conventional dressing. The yield reached 9718.0 kg/hm~2, whichwas 4 percent higher than CK.7. Compared to conventional cultivation technique, the two stages seedling-raising and high yieldcultivation technique could promote seedling re-greening 2 days, tiller emerging 5days, heading 7-8daysand ripening 7-8days earlier.8. Compared to conventional cultivation technique, the two stages seedling-raising and high yieldcultivation technique increased yield for 14%...