【作者】 张洪轩；

【导师】 周道玮；

【作者基本信息】 东北师范大学 ， 生态学， 2008， 博士

【摘要】 本论文提出了植物可塑性新的分类方法,并用该方法研究一年草本植物苍耳(Xanthium sibiricum Parin.)、荞麦(Fagopyrum esculentum Moench.)和曼陀罗(Datura stramonium L.)在不同密度和不同种植时间条件下的形态可塑性、生物量分配以及分生组织分配的策略,揭示了植物的不同特征在不同环境的可塑性差异。1.通过比较异速关系斜率和常数,我们将植物可塑性划分为四类:1.1关系可塑性:环境改变后,植物性状特征间的大小依赖关系消失;1.2尺度指数可塑性:异速生长的尺度指数(斜率)在不同环境条件下差异显著;1.3特征常数可塑性:异速生长的尺度指数没有显著差异,但是特征常数(截距)有显著差异;1.4生长速率可塑性:尺度指数和特征常数都没有显著性差异,但生长速率不同。2.植物的形态可塑性受到以下几个方面因素的影响:2.1不同的形态特征对环境的响应不同,在密度制约条件下,冠幅存在关系可塑性,叶片数则是特征常数可塑性,而直径是生长速率可塑性;2.2植物形态特征对不同环境的反应不同,冠幅在密度制约条件下存在关系可塑性,但在不同种植时间则不是这种可塑性;2.3异速关系与选择的分析指标有关系,异速生长是研究特征和个体大小之间的关系,个体大小即可用总生物量描述,有时也可用高度描述。我们的研究表明,不论是在密度制约还是在不同种植时间处理中,植物性状特征对总生物量的依赖程度明显增高,也就是说如果选择总生物量作为个体大小指标,那么得到的性状特征可塑性就相对较小;2.4对于不同分枝类型的植物,分枝角度和分枝数的可塑性存在很大差异。3.生物量分配的可塑性明显小于形态特征的可塑性。与形态特征一样,生物量分配的可塑性也受到环境和不同部分的生物量、选择的个体大小指标的影响。在不同种植时间条件下,生物量分配的可塑性比在不同密度制约条件下的可塑性要大。繁殖生物量分配的可塑性大于根、茎、叶生物量分配的可塑性。生物量分配对总生物量的依赖程度大于对高度的依赖程度。4.分生组织分配是一种研究生物量分配策略和植物可塑性的有用方法。不同的分枝结构导致在竞争条件下植物分生组织分配表现出不同的可塑性,通常繁殖分配的可塑性较小,营养生长的可塑性较大。更多还原

【Abstract】 This paper presented a new classification of plant plasticity, and this method was used to research on three annual plants Xanthium sibiricum Parin., Fagopyrum esculentum Moench. and Datura stramonium L. under density and sowing date treatments. The morphological plasticities, biomass allocations and meristem allocations were studied to reveal the differences of plasticities of different plant traits under different environments.1. According to allometric slope and constant, we divided plant plasticity into four categories:1.1 Relationship plasticity: the size dependences of traits disappear as the environment changes;1.2 Scale index plasticity: allometric scale index (slope) is significantly different in different environmental conditions;1.3 Constant feature plasticity: allometric scale index is not significantly different, but the characteristics constant (interception) is significantly different;1.4 Growth rate plasticity: allometric scale index and characteristics constant are not significantly different, but the growth rate is different.2. Morphological plasticity was affected by the following factors:2.1 The responses of different morphological traits to environment were different. Under density restriction condition, crown was relationship plasticity, the number of leaves was constant feature plasticity, and diameter was growth rate plasticity.2.2 The responses of plant morphological traits to different environments were various. Crown was relationship plasticity under density restriction condition, but was not the same type of plasticity under sowing date treatments.2.3 Allometric relationship is influenced by the indicator of plant size. Allometry is to study the relationship between characteristics and size, however the size can be described by total biomass, and in some cases by height. Our research found that both in the density or sowing date treatments, the dependence of traits on the total biomass was significantly higher than on height, indicating that if size is expressed by the total biomass, the plasticity of morphological features was smaller.2.4 The plasticities of branch and branch angle were different among different type of branching.3. The allocation of biomass plasticity was small than morphological traits plasticity. As well as morphological characteristics, the allocation of biomass plasticity was affect by the environment, different part of biomass, and the indicators of size. The allocation of biomass plasticity was higher under different sowing date treatments than density treatments. Reproduction biomass plasticity was higher than stem, root and leaf plasticities. The dependence of biomass allocation on total biomass was higher than on height.4. Meristiem allocation is an effective method to investigate plant allocation strategies and plasticity. Different architectures have different possibilities for, and different constraints on, plasticity of meristem allocation in response to competition. Reproductive allocation appeared to be the least plastic allocation pattern.更多还原