重庆三峡库区地处北纬29o～31o,年平均气温17.5～19.3℃,属龙眼栽培北缘区,露地育苗易受冬季低温冻害和盛夏播种期烈日高温影响,苗木生长慢,嫁接成活率低,合格壮苗少,出圃率仅50%～60%。重庆市果树研究所从2000年起,采用大棚营养槽播种,盖遮阳网降温,冬季覆无滴膜保温防冻和大 Chongqing Three Gorges reservoir area is located at latitude 29o ~ 31o, the annual average temperature is 17.5 ~ 19.3 ℃. It belongs to the northern margin of longan cultivation. The open field nursery is susceptible to cold frost damage in winter and high temperature in summer seeding. The growth of seedlings is slow, the survival rate of grafting is low, Qualified strong seedlings less, out of nursery rate is only 50% to 60%. Chongqing Institute of fruit trees from 2000 onwards, the use of greenhouse nutrition slot sowing, cover shade net cooling, winter coated drip film insulation freezing and large