水稻旱育秧在生产上存在三大问题： 2～ 3叶期生理性、病理性死苗严重；好气性的恶苗病严重，且易受地下害虫危害；苗床调酸、消毒、浇水等程序复杂。水稻旱育抛秧在此基础上还有三大问题：一是塑盘的一次性投入太大，以培育中苗秧为例，每亩 (1亩 =1／ 15公顷，下同 )本田需要 There are three major problems in the production of dry rice seedlings: the physiological and pathological dead seedlings are severe in the period of 2 ~ 3 leaf stage; the foul disease of aerobic nature is serious and vulnerable to underground pests; the procedures of acidification, disinfection and watering of the seedbed are complicated . On the basis of this, there are also three major problems: First, the one-time investment in plastic plates is too large. Take nursery seedlings for example. Each mu (1 mu = 1/15 hectare, the same below) needs Honda