【作者】 李冬林；

【导师】 向其柏；

【作者基本信息】 南京林业大学 ， 植物学， 2003， 硕士

【摘要】 本文主要从以下几个方面对浙江楠进行了研究：浙江楠种子的休眠机理与发芽条件的探讨；浙江楠一年生播种苗与留床苗的年生长规律；浙江楠苗期对光照条件的适应性；浙江楠苗期对土壤水分条件的适应性；浙江楠的播种育苗技术；浙江楠苗期对低温的抵抗能力。 (1)浙江楠种皮致密较硬，但种皮障碍不是种子休眠的主要原因，剥皮处理不适用于解除浙江楠种子的休眠。浙江楠种子的休眠属于生理休眠，低温层积处理和变温层积处理均能较好地解除浙江楠种子的休眠。赤霉素处理不适于浙江楠种子处理，处理后的种子大多数腐烂变质，种子的发芽率和发芽势均有一定程度的降低。 (2)浙江楠种子的萌发为子叶留土型。种子大多数多胚，一粒种子出1-3棵苗，稀出4棵苗。浙江楠一年生播种苗的高生长和直径生长均呈“S”形曲线，整个生长过程可以划分为出苗期、生长初期、生长盛期、生长后期。一年中，苗木速生期的高生长有3次生长高峰。浙江楠留圃苗在一年中的生长呈阶梯状，间歇性生长明显，属于全期生长类型。速生期大致经历180天。这一时期，苗木抽稍4次，因而有4次生长高峰。浙江楠主根性明显，一年生播种苗地下部分生长量大于地上部分生长量。 (3)播种密度与出苗率无直接相关。随着播种密度的加大，苗木径生长量明显减少，而高生长量变化不明显。浙江楠比较适宜的播种密度是160-200粒／m~2。 (4)全光条件下，单叶干重最大，表明叶片内部干物质积累多；遮荫条件下，比叶面积增大，但比叶重减少，表现为低的光合能力。光照强度影响苗木的外部形态，遮荫条件下表现为分枝数目减少、展叶数目减少、冠幅变窄，同化面积减小。遮荫条件下叶绿素a、叶绿素b、叶绿素总量均表现为增加；全光和弱度遮荫条件下，苗木具有较大的净光合作用速率，苗木生长旺盛，碳水化合物的积累较多，单株枝干重、根系生物量和总生物量都较大；重度遮荫条件下，苗木具有较小的净光合作用速率，碳水化合物的积累较少，苗木生长缓慢。 (5)浙江楠具有较强的水分调节能力，轻度干旱和水涝，苗木不会表现出明显的受害迹象。 (6)在南京，浙江楠一年生苗木冬季会受到一定程度的冻害，但多为轻微冻害，而两年生及两年生以上的苗木、幼树几乎不会受到冻害。更多还原

【Abstract】 The thesis studied mainly these contents on Phoebe chekiangensis Shang: The mechanism of dormancy and germination condition; annul growth rhythm of one-year seedlings and reserved seedlings; adaptability to light and soil moisture status in seedling stage; breeding techniques of seedlings; ability to resist cold.1.The seed coat of Phoebe chekiangensis Shang is hard, it is inferior in air permeability, on the other hand, it is superior in water permeability. After sacrificing seed coat, seeds were mostly decomposed, so the seed-coat obstacle is not the main cause of the seed dormancy, sacrificing seed coat treatment is not suitable for overcome the seed dormancy. We deduced that the seed dormancy of Phoebe chekiangensis Shang was caused by physiological factors, because both cold stratification and temperature -accelerated stratification treatments can overcome the seed dormancy. The treatment of GA is not also proper, because it will accelerate seeds to degenerate, percentage germination and germination capacity will decrease in some degree.2. Cotyledons of Phoebe chekiangensis Shang emerged when seeds germinating. One seed has more embryos, and it can germinate 1-3 seedlings, or 4 seedlings. The percentage germination of seeds was 60-78%. The growth patterns of height and diameter are fitted for S curve and can be simulated with Logister equation. At the same time, the growth period of both height and diameter is divided into 4 stages according to its growth rate: emergence phase of seedlings growth, initiation phase of seedlings growth, prosperous phase of seedlings growth, and later phase of seedlings growth. In one year, there are Stimes growth peaks. The growing of reserved seedlings present ladder-form in one year, belong to spring and summer growth type. Fast growth phase get through 180 days from the first growth peak to the last growth peak. In this phase, seedlings sprouted for 4times, so there are 4tim.es growth peaks. Taproot of Phoebe chekiangensis Shang is stronger, so the underground growth of one-year seedlings is more than the aboveground growth.3.The emergence rate of seedlings is different too, if sowing density is different, the biggest is 88.8%, the smallest is 63.2%, and average is 78.6%. The change is irregular, so there are not direct relation between the emergence rate of seedlings and sowing density. Along with the sowing density increasing, height growth almost not change, but root diameter growth falls. To ensure the seedlings quality and quantity, the best sowing density is 16-200grains/m2.4.On condition of sun shading, change of the individual leaf area is slight, but change of individual dried leaf weight is evident. In the full light, individual dried leaf is the heaviest, this indicate that the dried material accumulated is the most. On the other hand, on condition of sun shading, leaf area per dried leaf weight increases, but dried weight per leaf area and photosynthesis ability decrease. Light affects theoutside forms of seedlings: branching number and leaf number get small, while crown diameter of individual tree narrows, assimilation area grow few. In addition, content of chlorophyll a, chlorophyll b and chlorophyll a+b will increase on condition of sun shading. The net photosynthetic rate is higher on condition of full light and slight sun shading, seedlings growing is vigorous, the accumulation of CH2O is more, so dried leaf weight, branch biomass, root system biomass and total biomass per seedling all is more. On condition of heavy sun shading, the net photosynthetic rate of seedlings is low, the accumulation of GH2O is few, and seedlings grow slowly.5.The regulate ability of Phoebe chekiangensis Shang to soil water is strong, slight drought and flood will not bring evident influence to its growth.6. In Nanjing, the one-year seedlings of Phoebe chekiangensis Shang will suffer certain winter killing in winter, but this will not affect seedlings growing in next year, and net growth will reach 60-90cm. In general, two-year and above two-year seedlings更多还原