华北平原罗布麻种群生殖分株数量特征及变化规律

通过大样本取样调查,研究了华北平原罗布麻种群生殖分株的数量特征和生殖分配规律．结果表明,在籽粒完熟期,罗布麻种群单个生殖分株重为10．38±7．78g,蒴果生物量和蒴果数分别为1．57±1．59g和7．60±6．56个;种子生物量和种子数分别为0．34±0．33g和582．3±558．7个;生殖分配Ⅰ和生殖分配Ⅱ分别为12．98±7．94和2．75±1．69％．蒴果和种子形成分别需要分株积累1．42和1．77g以上的生物量．蒴果生物量、葫果数、种子生物量、种子数分别与分株总生物量呈极显著的（P〈0．01）线性正相关关系;蒴果数、种子数与茎叶生物量分配呈极显著的（P〈0．01）线性负相关关系;生殖分配Ⅰ、生殖分配Ⅱ和叶生物量分配呈极显著的（P〈0．01）线性负相关关系．单葫果的重量、种子重、种子数、种子毛重、胎座重分别和葫果的长度呈极显著（P〈0．01）的幂函数正相关关系．罗布麻种群生殖分株同时具有同速和异速2种不同增减过程的表型可塑性调节．     

不同地理种群两针松光合和生长特性的差异

为认识两针松中的赤松（Pinus densiflora）、长白松（Pinus sylvestris var. sylvestriformis）和樟子松（Pinus sylvestris var. mongolica）光合作用对环境变化的响应和适应特征,在其自然分布区内选择地理和气候差异显著的9个地理种群,采集成熟种子并播种于东北林业大学温室,2 a后,测定针叶的光合能力及其相关因子,并同时测定幼苗的株高和基径,比较种间和地理种群间差异。结果表明：赤松、长白松和樟子松种间最大光合速率（p=0.34）、呼吸速率（p=0.15）和表观量子效率（p=0.18）的差异均不显著;地理种群间表观量子效率（AQY）差异显著(p=0.08),其中兴凯湖种群表观量子效率最高,为0.084 5±0.002 4 mol CO₂·mol^-1 photons,较其他种群高13.10%~159.23%。地理种群间呼吸速率(R_d)差异显著(p=0.01),黑河和兴凯湖种群的呼吸速率最高（分别为1.62±0.18 μmol CO₂·m^-2·s^-1,1.52±0.30 μmol CO₂·m^-2·s^-1）,安图和东宁种群的呼吸速率最低,分别为0.40±0.01 μmol CO₂·m^-2·s^-1,0.34±0.03 μmol CO₂·m^-2·s^-1。地理种群间最大净光合速率(P_max)差异显著(p=0.02),其中兴凯湖、东宁、韩国、鸡东、二道白河、红花尔基种群的最大光合速率差异不显著,均值为18.36±1.81 μmol CO₂·m^-2·s^-1,高于安图、漠河、黑河种群。安图、漠河、黑河种群间最大光合速率差异不显著,均值为12.57±0.86 μmol CO₂·m^-2·s^-1。地理种群间的株高和基径差异均显著,其中韩国种群株高最高,黑河种群最低;基径兴凯湖种群最高,安图种群最低。株高和基径最大值约为最小值的3倍。两针松针叶的光合能力及其一些相关因子的地理种群间差异可能是其光合机构对种源地环境条件长期生理适应的结果。     

松嫩平原肥披碱草种群不同抽穗时间生殖分蘖株表型可塑性

每隔4 d对松嫩平原肥披碱草种群进入抽穗初期的生殖分蘖株进行大样本随机挂签,于籽实蜡熟期取样,分析5次采集样本生殖分蘖株数量性状的差异及其与缩短生殖生长时间的关系.结果表明:生殖分蘖株各数量性状指标均随生殖生长时间的缩短逐渐减小.生殖生长时间的缩短不利子生殖分蘖株的生殖生长、生殖分配和结实.抽穗时间越晚,对生殖分蘖株结实与生殖分配的影响越大.抽穗时间相差16 d,籽实生物量、结实率、生殖分配Ⅰ和生殖分配Ⅱ分别下降99.4%、98.8%、54.3%和99.2%.随生殖生长时间的缩短,株高呈直线函数下降,花序生物量、生殖分配Ⅰ和结实率呈指数函数下降,分株生物量、花序长、小花数呈幂函数下降,籽实生物量、籽实数和生殖分配Ⅱ呈对数函数下降.     

恢复措施对退化草地羊草种群有性生殖数量特征的影响

在封育和翻耙处理的退化羊草草地上,对羊草种群有性生殖的数量特征进行了比较研究．结果表明,翻耙样地羊草种群密度下降显著,生殖蘖密度变化不显著,生殖蘖穗长、节间长、生殖生长比率、穗节数、小穗数、小花数、饱满籽实数和结实率都有显著增长,籽实产量、净籽实重和千粒重分别是封育样地的2．68、3．49和1．3倍．在翻耙样地中,羊草种群发育有复小穗的生殖蘖比封育样地多16％,生殖蘖上复小穗的数量也显著增加,生殖蘖以相对少的小穗,生产了较多的小花和更多的籽实来提高种群的籽实产量．两个样地中羊草种群的生物量生殖分配在种群对生殖蘖RA1、生殖蘖对穗序RA4、穗序对籽实RA6 3个层次上无显著差异,而种群对穗序RA2、生殖蘖对籽实RA5的生殖分配差异显著,种群对籽实RA3的生殖分配差异极显著．     

中国特有植物艾比湖沙拐枣(Calligonum ebi-nuricum)居群内果实性状的变异

以中国荒漠特有植物艾比湖沙拐枣(Calligonum ebi-nuricum)果实形态特征为研究对象,对分布于原产区的同一居群12个样株的果实进行形态特征比较研究。通过每株30粒果实的喙长、果实长度、果实宽度、果实形状、瘦果长度、瘦果宽度、瘦果形状、刺毛长度、头部刺毛长度、两肋间距、两刺间距11个性状指标的数值分析表明：在株内与株间均有变异,株间果实性状变异较株内果实性状变异大;代表果实和瘦果大小指标正相关性极显著（p＜0.01）;两肋间距与瘦果形状呈负相关（r=-0.297**,p＜0.01）。研究结果证明：其果实形状和瘦果形状（长度、宽度及长宽比）较为稳定,可作为艾比湖沙拐枣的分种依据,而其它果实性状可塑性较大,只能作为分类的参考。该研究结果可供沙拐枣属其它种的准确分类参考。     

金沙江干热河谷车桑子生殖枝生物量分配的性别差异

以车桑子生殖枝为材料,通过野外调查、取样以及各器官生物量的测定,研究金沙江干热河谷地区车桑子不同性别植株生殖枝生物量分配特征。结果表明：（1）金沙江干热河谷地区车桑子种群雄∶雌性别比为0.11,极显著的偏离1∶1（P<0.001）,种群偏雌性。（2）车桑子生殖枝的形态特征和生物量分配特征均具有显著的性别差异;雌性植株生殖枝花朵生物量和总生物量显著高于雄性和两性植株（P <0.05）,而后两者之间无显著差异;生殖枝生殖分配具有显著的性别差异（P <0.05）,但生殖枝叶生物量无性别差异。（3）生殖枝生物量大小与花朵生物量、营养生物量均呈极显著正相关关系（P <0.001）。营养生物量与花朵生物量之间为显著正相关关系(P <0.01),生殖分配与生殖枝大小无相关关系。研究认为,车桑子生殖枝营养生长与生殖生长不具有权衡关系,且生殖分配不具有个体大小依赖性,特定生物量分配模式可能是对金沙江干热河谷区资源利用、环境适应的一种特殊形态模式。     

苏北海滨湿地互花米草种子特征及实生苗生长

摘　要　在江苏盐城新洋港滩涂由海向陆建立样地：零星互花米草(Spartina alterniflora)斑块(SAP)?稳定互花米草滩下边缘(SAFI)?2003年互花米草定居处(SAF03)?1989年互花米草定居处(SAF89),对互花米草的种子特征及幼苗生长进行了研究。结果表明：(1) 各样地种子产量有极显著差异(p< 0.01),大小顺序为SAP > SAF03 > SAFI > SAF89,种子产量与植株结实率、穗长、单穗种子数成正比。(2) 4月份SAP、SAFI、SAF03和SAF89互花米草短暂土壤种子库分别为673.7 /m2、2328.7 /m2、5948.8 /m2和3990.4 /m2,种子保存率分别为0.5%、3.9%、6.9%和15.8%,且在各样地差异极显著(p< 0.01)。(3) 7月份SAP、SAFI、SAF03和SAF89实生苗数分别为72 /m2、5 /m2、0和0。SAP与SAFI种子萌发率显著高于SAF03与SAF89(p< 0.01)。(4)表层土壤水分含量和种群内部光照衰减是影响实生苗生长的关键因素。在表层土壤水分含量高和低光照衰减的生境中种子繁殖对互花米草种群延续和扩张贡献较大。     

珍稀油料树种琴叶风吹楠果实和种子形态变异

以云南野生琴叶风吹楠(Horsfieldia pandurifolia)为材料,对39株树的果实和种子的形态进行变异分析。结果表明,果实和种子形态指标株间变异大,株内变异小。单株间果实表现出从卵圆形至长椭圆形的变异,果长4~7 cm,先端圆钝至锐尖,基部不同程度偏斜,与文献记录差异较大;单株间种子形态表现出从卵形、长卵形至细长形或近锥形的变异。单株平均种长变幅为25.05~35.66 mm,种宽为13.30~19.62 mm,长宽比为1.47~2.32,单因素方差分析表明此3个性状单株间差异极显著(p<0.01)。灰白色种皮具褐色斑块,种脐和胚位于种子基部,种子先端突尖或具短喙是稳定的性状,有重要的分类学价值。     

荒漠植物白刺属4个物种的生殖分配比较

选定乌兰布和沙漠地区白刺属4种植物为研究对象,通过对其样株在花期的各生殖构件的数量特征及生物量调查,系统研究了唐古特白刺(Nitraria tangutorum Bobr.)、西伯利亚白刺(Nitraria sibirica Pall.)、大白刺(Nitraria roborowskii Kom.)和泡泡刺(Nitraria sphaerocarpa Maxim.)4种白刺属植物在生殖枝水平上的生殖分配。结果表明:不同白刺属植物在分株高度、生殖枝长、生殖枝基径、单枝花数、花序干重、枝叶干重等生殖构件的数量性状方面均有显著差异,其中泡泡刺的各生殖构件的数量均最小;除了西伯利亚白刺的生殖分配值达到44.51%外,其余3种白刺的生殖分配值均没有超过20%。经统计分析,4种白刺种群的生殖枝长分别与分株高度呈显著(P<0.05)的直线性正相关关系;生殖枝花序干重与分株高显著正相关;4种白刺的生殖分配随着分株生殖枝生物量的增加而减少,即白刺的个体大小与生殖分配之间呈现负相关关系。这种生殖分配特点反映了不同白刺植物对生长环境的资源利用、与克隆繁殖的权衡及对生态适应的策略。     

放牧影响下羊草种群生殖生态学的研究

在种群水平上系统研究了放牧对松嫩草原关草种群无性繁殖、有性生殖和生物量的生殖分配的影响。结果表明,放牧制约了羊草种群无性繁殖和有性生殖的更新途径,表现在随放牧强度增加,无性繁殖体营养技密度、根茎牙密度和有性生殖体种子生物量、结实数和生殖枝分化率等指标均显著下降,是生牧后下降迅速。随放牧强度增加,关草种群根茎生物量的分配比例显著增加,而同化器官、非同化器官和种子生物量分配比例都显著下降,极牧阶段几科     

内蒙古中东部草原不同生境克氏针茅（Stipa krylovii Roshev.）种群的形态差异分析

对内蒙古中东部草原分布的克氏针茅进行了种群内和种群间的形态差异分析。结果表明：（1）种群内不同的形态性状存在不同程度的差异;（2）种群间生殖枝中的一部分形态性状以及营养枝高度和营养枝干重均存在较大差异;（3）每穗小花数、每穗籽粒数、每穗小穗数、生殖枝高、穗干重、生殖枝干重、每穗种子重、种子重/生殖枝重比等性状的变化趋势相同,均表现为随生境条件变差而增加,即在生殖上投入增加以增大适合度;（4）主成分分析表明穗长、种子重/生殖枝重比、每穗小花数、每穗籽粒数、生殖枝高、基盘长、第二芒柱长、营养枝高、千粒重、芒针长是不同种群差异的主要指标。这些形态性状的差异可以看作克氏针茅对不同生境的适应性表现。     

互花米草与芦苇耐盐生理特征的比较分析

以天津滨海滩涂外来植物互花米草和本地种芦苇为研究对象,对两种植物根、茎、叶3个器官保护酶(超氧化物歧化酶(SOD)、过氧化物酶（POD）、过氧化氢酶(CAT))和膜脂过氧化产物丙二醛(MDA)、游离脯氨酸、可溶性糖以及质膜相对透性及其季节动态变化进行了测定。结果表明：（1）互花米草体内SOD、POD、CAT酶活性、游离脯氨酸、可溶性糖含量在整个生长季节较芦苇偏低;（2）游离脯氨酸和可溶性糖是互花米草和芦苇体内重要的有机渗透调节物质;(3)两种植物根、茎、叶的质膜相对透性在整个生长季节基本保持稳定,但互花米草质膜相对透过性高于芦苇。该研究有利于解释互花米草适应潮间带生存环境的部分机制,并且从生理生态学特性角度说明其竞争力高于芦苇的原因。     

3种同域分布的杓兰属植物的种子及杂交种子特征分析

杂交种子研究在一定程度上能说明是否存在杂种不活机制,在植物生殖隔离研究中具有重要意义。通过对同域分布的西藏杓兰(Cypripedium tibeticum)、黄花杓兰(C.flavum)和褐花杓兰(C.calcicola)的自交、异交、杂交种子的形态特征及活性进行分析,发现3种杓兰属植物两两之间均可产生杂交种子,且杂交种子活性较高,杂交种子与其他处理所得种子的外观、表面纹饰无显著性差异;种子宽度、种子长度、有胚率、着色率并没有比自交或异交种子显著低。这一结果表明这3种同域杓兰属植物种与种之间具有相当高的亲和性,它们之间不存在明显的杂种不活机制。黄花杓兰与西藏杓兰或褐花杓兰间的传粉者大小明显不同,黄花杓兰由丽蝇和熊蜂工蜂传粉,而西藏杓兰和褐花杓兰由体形较大的熊蜂蜂王传粉,传粉者隔离已使得它们之间的物种界限比较清晰,因此已经没有必要再产生杂种不活等其他隔离机制。而西藏杓兰与褐花杓兰的传粉者相同,又没有明显的杂种不活隔离机制,暗示它们之间有其他合子后隔离机制或应将其合并为一个种。     

扎龙湿地不同生境芦苇分株的形态特征及生物量分配的异速关系

不同环境条件下的植物个体可以表现出形态特征的分异和物质分配的权衡与调整。采用大样本抽样调查与统计分析方法,比较研究扎龙湿地不同生境芦苇(Phragmites Australis)生殖株和营养株的形态特征以及生物量分配的异速关系。结果表明:在9月末,盐碱生境、旱生生境、湿生生境和水生生境芦苇分株的生长表现出较大的生态可塑性,株高和株重均以盐碱生境最小,水生生境最大,最大值与最小值的比值分别为1.3-3.3和1.8-5.1,分株生长在种群间的变异度高于种群内,与营养株相比,生殖株的变异度较低;分株的支持分配与生产分配的比值为1.8-4.2,生产分配以盐碱生境最高,以水生生境最低,而支持分配和生殖分配表现与生产分配相反的序位;生殖株的花序长和花序重与株高间呈直线函数形式增长,株高和株重低于种群平均值的20%和35%的分株不进行有性生殖;叶重、叶鞘和茎重以及分株重与株高间呈幂函数形式的异速生长关系。植物通过改变个体的形态特征以及调整构件间生物量分配适应不同环境,而受遗传因素控制的构件间生长关系却相对稳定。     

Optimal Reproductive Strategy of Plants, with Special Reference to the Modes of Reproductive Resource Allocation

Abstract A growth model for reproductive energy allocation pattern and schedule is proposed. Assumptions are as follows: (1) the assimilation rate for an individual is given by a logistic curve of vegetative dry weight; (2) size variability is expressed by the parameter W of the logistic curve (asymptotic value of vegetative dry weight); (3) a plant controls allocation of the assimilate to vegetative and reproductive structures so as to maximize the reproductive energy investment at the end of the growth period. The models were analyzed in comparison with field and experimental observations and gave reasonable explanations for the reproductive allocation pattern of individuals which reflects ecological preferences and life history characteristics, such as environmental conditions of habitats (stable or changing), length of life span (annual, biennial or perennial) and growth form (erectophile or planophile). Decreasing RA (reproductive allocation) with individual size and delayed switchover time from vegetative to reproductive growth were found in plants which occur in stable environments and have a more or less fixed growth period; in those which occur in changing environments where growth period depends on individual size, RAs that remain constant or increase with variations in individual size and early switchover time were detected. Most perennials conform to the former case, but annuals and biennials conform to the latter case. Under extremely overcrowded conditions, planophiles, which are much more subject to crowding effect than erectophiles, tend to have increasing RA with increasing size, while erectophiles tend to have almost constant RA irrespective of size. These trends are discussed in the light of the life history characteristics and ecological distribution of plant species studied.     

Life History Studies on the Genus Trillium (Liliaceae) I. Reproductive Biology of Four Japanese Species

Abstract Four Japanese Trillium (Liliaceae) species which are representative perennial herbs of the temperate deciduous forests— Trillium kamtschaticum (2x), T. apetalon (4x), T. tschonoskii (4x) and T. smallii (6x)—were studied for their reproductive characteristics, e.g., patterns of reproductive resource allocation and reproductive output.
In spite of the differences in ploidy levels (from 2x to 6x), all four species showed very similar reproductive traits. It became evident that in response to the increase in reproductive allocation to total reproductive organs (RA), the number of seeds produced per plant (P_N) clearly increased. This trend is well in accord with the relationship found in four North American species and also several temperate woodland perennial herbs which occur in closed, stable and predictable environments, and possess typical xenogamous breeding systems. Although there is no conspicuous trend between ploidy levels and P_N, one of the significant differences noted in this study was in seed weight, which ranged from 2.93 mg in diploids, to 3.42–3.45 mg in tetraploids, and to 4.47 mg in hexaploids.     

Reproductive allocation and fruit-set pattern in the euhalophyte Suaeda salsa in controlled and field conditions

Reproductive allocation and fruit-set pattern are important characteristics of halophytes, and these characteristics were investigated in euhalophyte Suaeda salsa (S. salsa). The plants comprised of those treated with 1 mM (control) or 500 mM (high salinity) of NaCl for 120 days in a glasshouse and those collected in the field. In controlled conditions, high salinity increased reproductive allocation and the number of fruits and seeds in each node of the branches. In field conditions, reproductive allocation and the number of fruits and brown seeds in S. salsa at the upper tide line were higher than at the lower tide line. There were more fruits and seeds distributed in the central part than those in the base or top of branches in both controlled and field conditions. Soil organic matter, total nitrogen and total phosphorus content at the upper tide line were lower than at the lower tide line. An opposite trend could be observed in the total soluble salt, Na⁺ and Cl^? content in soil. In conclusion, the fruit-set pattern of S. salsa may be affected by both resource constraints and resource allocation. Reproductive allocation and fruit-set pattern may ensure the establishment of S. salsa in high saline and low nutrient environments.     

Clonal integration enhances flood tolerance of Spartina alterniflora daughter ramets

Recently, considerable attention has been paid to the invasion of the clonal plant Spartina alterniflora into coastal wetlands at lower elevations. In this experiment, we tested whether clonal integration improved flood tolerance in S. alterniflora daughter ramets. Daughter ramets at two growth stages (young and old ramets) were flooded to water levels of 0, 9 and 18 cm above the soil surface, and the rhizomes between mother and daughter ramets were either severed or left intact. Biomasses of connected ramets grown in controls or in shallow and deep water treatments were 119%, 108% and 149% higher in the old ramet group than those of severed ramets, respectively, whereas they were 3.0, 3.3 and 11.2 times higher in the young ramet group, respectively. At the end of the experimental period, the shoot height, connected with young ramets, in shallow and deep water treatments increased by 19% and 26%, respectively, over that in the control treatments, whereas the old ramets increased by 11% and 39%, respectively. In contrast, the shoot height of the severed young ramets was 27% and 26% lower in shallow and deep water treatments than in the control treatment, respectively. However, the shoot height of the severed old ramets remained constant with increasing water depth. We conclude that clonal integration enhances the flood tolerance of S. alterniflora daughter ramets, and the trait of clonal integration plays more important roles in severe flooding stress conditions and at early growth stages.