Effects of Seedling Raising Methods and Seedling Strengthening Agent on Seedling Growth of Machine Transplanting Rice in Wheat-rice or Wheat-rape Double Cropping Area in South Region of Shanxi Province

Field experiment was carried out to study the effects of seeding raising methods and seedling strengthening agent on seeding growth of mechanical transplanting rice in wheat-rice or wheat-rape double cropping in south region of Shanxi Province. The results showed that the suitable transplanting period was 33 days after sowing(DAS)in wet seedbed and 26 days after sowing in dry seedbed. In terms of seedling emergence rate, the seedlings grown without fertilizer performed better than the seedlings grown with fertilizer. In terms of seedling qualities, the seedlings grown with nutrition agent performed better than the seedlings grown with strengthening agent and without fertilizer. Compared to wet seedbed seedling raising, the seedling in dry seedbed can balance the growth of shoot and root, and the seeding emergence rate was higher. Overall, it appeared that a dry seedbed in the greenhouse was the better option to produce vigorous seedlings with better qualities in wheat-rice or wheat-rape double cropping area in south region of Shanxi Province. So, the over age seedlings was the limited factor for mechanical transplanting rice, it can be solved by postpone the sowing date in a dry seedbed, because greenhouse can improve the temperature in rice seedlings stage.