深山含笑引种苗期试验初报

A study on the introduction and raising seedling of Maudia Michelia

育苗试验表明，原分布在中亚热带的深山含笑基本能适应北亚热带南京地区的气候，正常生长发育。其种子发芽出土、形成幼苗需要较高积温，在塑料薄膜棚内，约需４０ ｄ。苗期生长呈单峰“∧”字形，４～６ 月生长缓慢，生长量占全年１４－４ ％ ；７ ～９ 月速生，生长量占全年８１－６ ％ ；８ 月生长量呈现峰值，占全年３９－９ ％ ；１０ ～１１ 月生长趋于停滞。１ ａ 生苗高１１－５ ～２９－０ ｃｍ ，平均高２３－４ ｃｍ ；２ ａ生苗高６５ ～１０６ ｃｍ ，平均高９４－０ ｃｍ 。苗木不耐寒，在－ ４ ℃自然低温时，１ ａ 生苗寒害率达３０％ ，需采取防寒措施。叶面喷施硼、锌、锰、镁等微量元素和磷钾肥液，能显著促进生长，减轻寒害。苗木高生长与气温、日照、蒸发量关系密切，适当减少日照，降低蒸发，增温保湿是保障引种的关键。

Michelia maudiae Dunn were introduced into Nanjing of northern subtropical area in 1997.The seedlings growth characters and adaptability were studied.The results showed that the germination and seedlings emergence need higher accumulation temperature and about 40 days in plastic film arch.Seasonal growth of seedlings appeared that it grew slowly in April and June;it grew fast from July and to appeared peak in August(the growth was 39 9% of total annual growth)and tended to stop in October and November.The growth curve showed one peak as a “∧”shape.The l year old seedlings height growth varied from 11 5 to 29 0 cm and the average height was 23 4 cm.The 2 years old one was from 65 0 to 106 0 cm and the average value was 94 0 cm. The 1 year old seedlings freezing damage rate was 30% when the low temperature was -4℃ in field.Therefore the winter protection measures was necessity.The seedling cold injury was decreased and the growth was enhanced when foliage sprayed micronutrients element as B,Zn,Mn,Mg and phosphor potash fertilizer in autumn.Because there were closely relationship between height growth and climatic factors as air temperature,sunshine and evaporation.The important technique were suggested such as shading for decrease evaporation and heating with humidifying on raising seedling. Authors address:Jiangsu Academy of Forestry,Jiangsu Nanjing 211153,China