杉木球花特性及其种子园花粉量的研究

本文以姥山杉木初级种子园、杉木种源林和普通杉木林为对象,对杉木雌雄球花在树冠中的分布及其发育过程,雄球花特征值频率分布,雄球花大小分类及花粉产量等进行了研究。结果表明,杉木雌雄球花在树冠中的分布具有成层性。雌球花主要分布在树冠上、中部,雄球花则主要分布在下、中部。杉木雄球花及花粉特征值频率分布为偏态分布。雄球花的大小可按小孢子叶球数平均值一倍的标准差,分为大、中、小3类。花粉的客重为656.071 8mg/cm~3。用容重法测得的每个孢粉囊产生的花粉为3700粒。姥山杉木种子园平均每株母树产生花粉约697 g,约35.1亿粒。整个种子园产花粉约12681kg,约6.5478×10~(14)粒。偏雄,宜进行适当改造。     

我国松树种子园开花习性研究概述

对国内松树种子园开花物候、雌雄球花产量及其空间分布规律、花粉密度与飞散规律、球花产量与生长性状间的关系等方面的研究结果进行了综述.并对今后的发展提出了展望.     

油松种子园花粉飞散规律的研究

我们于1984—1986年连续三年在兴城油松种子园进行了观测,研究了油松雄球花发育成熟散粉的生物学特性;结合散粉期内气象因子特点,分析了花粉浓度的日变化和时变化类型;着重探讨了花粉在山地条件下的传播特点及种子园内花粉分布的特性;并根据实验结果,对山地种子园的建立和管理提出了一些看法。     

我国油松种子园研究现状

对油松种子园开花生物学特性、球花分布规律、花粉密度与飞散规律、种实品质差异成因及经营管理等方面的研究状况作了较为系统的综述,并对进一步研究提出展望,为油松种子园建设提供参考。     

杉木花粉生态学特性研究

本文自1984—1989年,以杉木种源林、浙江姥山和长乐杉木种子园及普通杉木林为研究对象,在实地调查和定点观测的基础上,对杉木雄球花散粉的解剖学基础和散发节律,雌雄球花及花粉以风作为花粉传播媒介的适应性变化,花粉的传播、沉降及空间分布进行了研究。提出杉木种子园宜选在水体旁,种子园的隔离照离应大于1500m,减少直至消灭自交的有效方法是选用雌性和雄性杉木无性系建造种子园,雌、雄杉木的比例为11:4。雄株应比雌株高1.5—2倍,株行距为3×2.5m、3×3m、3×4m。     

思茅松无性系种子园雌雄球花分布特性及人工辅助授粉的研究

在云南省林业科学院普文试验林场思茅松种子园开展了 16个无性系的雌雄球花空间分布特性及人工辅助授粉的研究 ,结果表明 :各无性系间雌雄球花数量及雌雄比均差异极显著 ,存在偏雌偏雄的变异 ;雌雄球花数量的空间分布存在一定的规律性 ,在垂直方向上 ,79%以上的雌球花分布于树冠的中上部 ,80 %的雄花分布在树冠的中下部 ;在水平方向 ,东、西、南、北 4个方位球花数量的分布基本一致。种子园的落花现象比较严重 ,且不同无性系的落花率不同 ;人工辅助授粉有助于雌球花的保存和座果率的提高     

林木种子园生殖系统研究进展

本文对种子园生殖系统中亲本开花物候、配子产量、球果和种子败育、授粉机制、球花分布对种子园遗传效率的影响及其研究进展作了综述。论述了开花物候、球花产量与配子贡献以及种子园生殖系统遗传效率的关系。不同亲本开花物候及授粉机制的差异限制了亲本之间的基因交流 ,雌雄球花产量、球果败育及其雌雄球花空间分布的差异都会引起亲本配子贡献的变化 ,并最终影响种子园生殖系统的遗传效率。为提高种子园种子的遗传品质和遗传多样性 ,更系统深入地研究种子园生殖系统是必要的     

杉木种子园开花结实规律研究的综合评述

了解和掌握树木的开花结实规律对于提高种子园种子的产量与品质起着关键的作用.随着我国杉木种子园营建面积的扩大与营建技术的深入研究,在种子园开花结实规律方面进行了大量卓有成效的工作.本文对杉木种子园开花生物学特性,球花分布规律、花粉飞散传播规律、种实产量预测、种实品质差异成因及其与选育层次的关系等方面的研究状况作了较为系统的综述.     

思茅松无性系种子园雌雄球花分布特性及人工辅助授粉的研究

在云南省林业科学院普文试验林场思茅松种子园开展了16个无性系的雌雄球花空间分布特性及人工辅助授粉的研究，结果表明：各无性系间雌雄球花数量及雌雄比均差异极显著，存在偏雌偏雄的变异；雌雄球花数量的空间分布存在一定的规律性，在垂直方向上，79％以上的雌球花分布于树冠的中上部，80％的雄花分布在树冠的中下部；在水平方向，东 西、南、北4个方位球花数量的分布基本一致。种子园的落花现象比较严重，且不同无性系的落花率不同；人工辅助授粉有助于雌球花的保存和座果率的提高。     

辽宁兴城油松种子园无性系开花习性的研究

1982－1984年在辽宁兴城种子园，3年的观测表明，49个无性系花期早晚和长短有较大差别，这与无性系本身的特性，花期前的积温，花期内的温度和湿度以及球花着生部位等有关，由于种子园中有部分无性系花期不遇，由此减少的杂交组合至少在1／10以上，嫁接后第九年雌球花产量较上年成倍增加，到第10年总产量仍持续上升，但早期结实量大于平均水平的约30％无性系，雌球花产量已有下降趋势。迄今种子园中开花株数和雄球花产量稳定增长，多数无性系植株平均着花量约在700个上下，但仍有约半数无性系的1／3植株尚未开雄球花，种子园中花粉量不足，每公顷约产花粉2．8－3．7公斤，且种子园各无性系花粉比例极不平衡，5个无性系的雄花量占部量的一半以上。     

山地条件下油松花粉的传播及其对该地形中种子园的花粉侵染

1988～1989年在卢氏油松无性系种子园和人工油松林内外设立花粉采样点,观测花粉在不同山地类型的传播特点及对下风方向种子园侵染的危险性。结果表明:油松花粉传播受地形、散粉日期、风速、大气湿度等因素的影响。风速大、空气干燥,天气晴朗的日子,散粉速度快,传粉距离远,在开阔地、抬升地、对坡地形中,距离花粉源数百米甚至数千米地点的花粉浓度常高于花粉源的花粉浓度,对坡地形尤为显著。因而,在营建山地种子园时,至少应保持1000 m的隔离距离。本文还结合实验结果,对山地种子园的建立和管理提出了一些看法。     

Flowering and Airborne Pollen Occurrence in a Pinus sylvestris Seed Orchard Consisting of Northern Clones

To explain the high background pollination rate detected in earlier studies, this study investigated the flowering phenology of a Scots pine seed orchard with respect to airborne pollen occurrence during 1992 and 1993. The receptive period of the female strobili and the shedding period of the male strobili were observed visually. Airborne pollen was monitored with Rotorod traps located inside and outside the seed orchard. There was no time gap in the onset of flowering between the earliest female and male strobili in 1992. Female flowering began 3 days earlier than male flowering in 1993, and the earliest strobili were probably pollinated by pollen transported long distance from more southerly areas. The almost simultaneous peak in pollen occurrence inside the seed orchard and in surrounding pine stands indicates that the seed orchard clones are not temporally isolated from sources of contamination. However, pollen concentrations inside the seed orchard were higher than those in the surrounding stands. Therefore, flowering phenology cannot sufficiently explain the observed pollen contamination rates in this seed orchard.     

Supplemental mass pollination in a seed orchard of Pinus Sylvestris L. investigated by isozyme analyses

Isozyme‐analysis techniques have been applied to test the efficiency of supplemental mass pollination in a seed orchard of Pinus Sylvestris. Mass pollination was done on one single occasion before the general pollen dispersal. The results of isozyme analyses of seed after mass pollination demonstrate that it is possible to introduce desirable genes into the seed orchard crop. Mass pollination without isolation of female strobili gave an average contribution of 4% to the total fertilizations and after isolation of female strobili 26.5%. The main conclusion is that supplemental mass pollination offers very interesting possibilities for breeding, particularly if some kind of isolation of the female flowers is made. It can increase the seed quality as well as improve the breeding value of the seed orchard. More attention should be paid to increasing the efficiency of the controlled pollination. It is suggested that in the future, more effort is invested in improving the technique of mass pollination.     

马尾松无性系种子园球花量变化研究

对福建漳平五一国有林场马尾松种子园雌、雄球花量观察和分析。结果表明 ,种子园雌、雄球花产量变异主要来源于年份、无性系、无性系与年份互作等效应。它们二者在无性系间、无性系与年份互作间遗传相关关系不显著 ,而在无性系内分株间、年份间相关达到极显著和显著水平。并结合实践 ,提出建园材料再选择 ,以及对现有种子园采用选择性疏伐等提高种子园球花产量 ,克服雄球花显少有效技术措施     

Effects of crown-pruning on seed and pollen cone production in two lodgepole pine seed orchards in British Columbia

The effects of top pruning on subsequent seed and pollen cone production in lodgepole pine (Pinus contorta Dougl.) grafted clones in two seed orchards were evaluated. In the older orchard (14 years old), three pruning regimes were applied: an untreated control, a moderate pruning where 25% of the crown was removed and a severe pruning where 40% of the crown was removed. In the younger orchard (ten years old), only a control pruning and a severe pruning (50% of crown removed) were applied. Five-year seed cone production was lower in treated ramets compared to controls in both orchards. However, when cumulative seed cone yields were adjusted for reduced tree heights after pruning, differences were no longer significant in the older orchard. Strong clonal variation was observed in seed cone yields in both orchards. Pollen cone development was less variable among treatments in the older orchard. In the younger orchard, controls consistently produced heavier pollen crops. Pruning recommendations for similar orchards are made and results discussed for reducing the impacts of losses in seed cone yields.Deceased     

利用开花结实信息段预测中、幼龄杉木球果产量的研究

林木种子产量预测预报是种子经营工作的重要环节。传统的预测预报方法一般都比较粗放,难以满足当今生产管理的需要,如产量目测法、标准枝法等。近年来有人应用气象学法和灰色动态模型预测法预测林木种子产量,尽管工作量小,技术先进,但由于难以获得可靠的产量历史资料,难以普遍应用。一个好的预测方法必须具备下述三个条件:1.时间超前;2.精度高;3.简便实用。基于这一思路,本文在研究杉木球花及球果在树冠上分布规律的基础上,探讨了利用开花结实信息段预测杉木种子园和一般林分球果产量的方法。     

马尾松第一代改良无性系种子园建园材料选择

以福建省漳平五一国有林场马尾松第一代无性系种子园为研究群体,在对园内无性系及其子代家系测定数据分析基础上进行无性系再选择,重建改良代种子园。结果表明,子代生长量与当代无性系产籽量和雌雄球花量,在家系与无性系水平上差异极其显著,且不同程度受遗传控制,具有一定选育潜力。采用综合评定和独立淘汰相结合的方法,能实现性状兼优的无性系再选择。以一代(CK1)为对照,从160个无性系中再选择30个无性系建立的改良代种子园育种效果显著,其遗传增益估值,8年生子代材积提高10.9%,产籽量和雌、雄球花量分别提高49.1%、18.9%、7.6%;以母树林混合种(CK)为对照,2个选择阶段,8年生子代材积累计遗传增益估值18.1%。     

马尾松球果小卷蛾幼虫混合种群空间分布型与抽样技术研究

马尾松球果小卷蛾幼虫混合种群空间分布型与抽样技术研究兰星平，杜凌（贵州省森林病虫检疫防治站贵阳５５０００１）（贵州省种苗站贵阳５５０００１）陈恩军，黄丽（林业部种苗总站北京１００７１４）（贵州黄平县横坡林场黄平５５６１００）关键词马尾松，种子园，球果...     

Temporal and spatial variation of pollen yield in natural populations of Pinus roxburghii

Male components of the reproduction process in Pinus roxburghii were investigated for their variation in time and space as well as pollination,viz.flowering phenology,pollen production variability and pollen dispersal,for five successive years at two different locations (at the lower and higher elevations).The study reveals that elevation and the hour of the day are the main determinants of anthesis and microsporangium dehiscence,because both are related to temperature and humidity.The receptivity of ovulate cone strobili or female strobili occurred earlier at the lower elevation than at the higher elevation,with a longer receptivity period in the latter case.The phenology of male and female cones varied significantly between years and elevations.The determinations of pollen yield considered various sources of variability,i.e.,the number of pollen strobili per branch,strobili per tree,microsporangia per tree and pollen grains per tree.Each of these parameters revealed significant year-to-year and elevation effects.Year-to-year variation in the production of pollen cone and pollen grains with mass production after a three-year period revealed a three-year cycle of masting in pollen production in P.roxburghii.The pollen dispersal decreased quickly with distance from the pollen source.As a consequence,a distance of 600 m was proposed as a minimum to prevent contamination by pollen in the management of seed orchards.The results ultimately suggest that the ample production of pollen grains per tree along with flowering synchrony and long dispersal of pollen grains results in homogeneity in large populations.