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1.
1.5代杉木种子园不同无性系生长和结实性状的评价   总被引:1,自引:0,他引:1  
为进一步优化1.5代杉木种子园的质量,通过对福建漳平杉木种子园内21个杉木无性系生长和球果特征的调查,分析不同无性系生长和结实性状的差异及其相互关系,采用层次分析法对不同无性系的生长性状和结实性状进行综合评价。结果表明:1.5代杉木种子园不同无性系之间的生长和结实性状存在明显差异;不同无性系的结实量、球果体积、球果鲜重与其种子产量显著相关,生长性状与结实量、结实量与种子发芽率的相关性不显著。根据不同无性系生长性状和结实性状的综合评价结果,有6个无性系具有生长快且结实量高的特性,可作为重建1.5代杉木种子园的材料。  相似文献   

2.
本文针对落叶松球果花蝇各虫期特点,采取蛹期消灭、诱杀成虫、毒杀幼虫等综合防治措施,收到良好的效果,使球果被害率下降了90%。通过对落叶松球果花蝇进行综合防治,大幅度减少了良种损失,经济效益显著,对落叶松种子园、母树林建设具有实际意义。  相似文献   

3.
对福建五一林场马尾松(PinusmasonianaLamb.)种子园20个无性系的种子品质及单株球果产量进行了统计分析,结果表明:无性系间在种子品质上存在着极显著差异,而无性系内除种子千粒重差异不显著外,其他性状(果径、果长、单果重和单果出籽数)差异极显著。20个无性系的单株球果产量大多逐年上升。同时对不同年份无性系结实的稳定性进行分析,划分出较稳定的无性系和较不稳定的无性系,评选出了种子高产品质优良的无性系。  相似文献   

4.
为了分析林分因子和气候因子与天然红松球果产量之间的关系,在凉水自然保护区原始阔叶红松林中分别设置3块面积为50 m×50 m的标准地和3块林缘标准地,调查了标准样地内每株红松的结实量并测定林木因子(胸径、树高、树龄等)与气候因子(温度、相对湿度、降水量等),采用相关分析法确定显著影响因子。结果表明:相同林分条件下,单株球果产量随胸径、树高的减小而增加,胸径与球果产量的拟合度更好;不同林分条件下,单株球果产量与林龄的变化趋势有一定关系,但是不显著;不同年度间平均单株球果产量与球果成熟当年5月份月均温度、当年6月份月均温度、前一年6月份降水量等气候因子相关关系显著。  相似文献   

5.
球果花蝇是远东地区的重要球果种实害虫。尤其是在我国东北地区 ,由于球果花蝇的危害已严重影响了落叶松种子产量 ,进而影响到落叶松的造林与更新。本文系统地总结了近些年危害落叶松、云杉、冷杉种实的球果花蝇的研究进展及存在的问题。文中还涵括了作者的一些原始研究数据和尚未发表的新结果。  相似文献   

6.
球果花蝇是远东地区的重要球果种实害虫。尤其是在我国东北地区,由于球果花蝇的危害已严重影响了落叶松种子产量,进而影响到落叶松的造林与更新。本文系统地总结了近些年危害落叶松、云杉、冷杉种实的球果花蝇的研究进展及存在的问题。文中还涵括了作者的一些原始研究数据和尚未发表的新结果。  相似文献   

7.
杉木种子园种子产量及其主导影响因子的分析   总被引:6,自引:0,他引:6       下载免费PDF全文
 为研究我国杉木种子园产量的主导影响因子及影响效应,调查收集了安徽西田、福建洋口和官庄、广东小坑4个林场杉木(Cunninghamia lanceolata)种子园历年种子产量及与种子生产年份对应的有关气象资料,以开花受粉、幼果发育各个不同时期的20个气象因子与种子产量进行逐步回归分析,探讨我国杉木种子园产量的大小年现象及周期特征。研究结果表明,杉木种子园投产初期大小年现象不显著,投产中、后期大小年现象出现的年度及周期特征完全一致,种子大小年周期一般为2~3年。在同一地区气候条件相似的情况下,即使立地条件、  相似文献   

8.
油松人工林球果生物量的初步研究   总被引:2,自引:0,他引:2  
本文是用实测油松人工林平均木球果生物量的方法,来研究不同立地条件、测树学因子与油松人工林球果生物量的关系。结果表明,油松球果生物量以山脊、阳坡最多,阴坡次之,山洼最少;油松球果生物量与林木生长级之间呈正相关;在单株林木的树冠部位上是以上、中部的球果生物量最多,下部最少,向阳面显著多于背阴面。胸径、树高与球果生物量之间呈直线正相关,并推导出预测油松球果生物量的回归方程。  相似文献   

9.
樟子松松针红斑病是大兴安岭地区发生的主要病害,种子园中发生此病害严重影响樟子松的果实的产量和质量。本文对樟子松种子园松针红斑病的调查和防治进行了论述。  相似文献   

10.
《环境昆虫学报》2013,35(1):28-32
掌握球果角胫象Shirahoshizo conifera Chao在云南潜在分布区,对了解其危害和防控具有重要的意义。本文利用球果角胫象的分布点数据和环境因子数据,通过Maxent生态位模型预测其在云南的潜在分布区。结果表明:球果角胫象的潜在分布区主要集中滇中地区;在ArcGIS中进行显示与风险等级划分,按栅格数值的大小将球果角胫象的适生范围分为4级,分级标准为:高适生区、中适生区、低适生区、非适生区,经ROC曲线分析法验证,Maxent生态位模型的AUC值为0998,表明预测获得了较好的效果。  相似文献   

11.
油松球果小卷蛾成虫的产卵选择   总被引:4,自引:0,他引:4  
油松球果小卷蛾Gravitarmata margarotana(Heinemann)是广泛分布的一种松属球果和枝梢害虫,在我国北方油松良种基地主要危害油松球果。用油松和华山松球果做产卵选择试验,以及2树种球果浸提液对产卵影响的结果表明,油松球果对产卵雌虫具有更强的引诱作用;不同油松球果类型的着卵量结果表明,红色球果类型的着卵量显著高于绿色球果类型,并且同一颜色球果,有刺类型的着卵量多于无刺类型。球果挥发成分结果表明,油松球果挥发成分有6个组分,而华山松球果挥发成分只有5个组分,与油松球果相比,无β-非兰烯组分;油松不同株系类型球果挥发成分只表现出含量上的差异。  相似文献   

12.
Guy-ÉTienne Caron 《Grana》2013,52(6):313-320
Pollen monitoring was conducted over three years (1987–1989) in a 12.4 ha Picea mariana (Mill.) B.S.P. (black spruce) seedling seed orchard established from 1979 to 1984. Pollen traps were installed around and within the orchard and collected daily. Pollen-cone production was highest in 1988 with an average of 0, 11, 20, and 38 cones per tree for 5-, 8-, 9-, and 10-year-old trees. Trees of the oldest section of the orchard bore about 60% of the total number of orchard pollen cones in 1987 and 1988 but only 26% in 1989. Pollen contamination during seed-cone receptivity was important in all three years assessed. The increase in pollen contamination from 1988 to 1989 resulted, in part, from 1) the roguing of 63% of trees in the oldest section of the orchard and 2) a 17-fold decrease in orchard pollen production from 1988 to 1989 compared to a 5-fold decrease from contamination sources.  相似文献   

13.
以进入生殖阶段的8个天然云南铁杉(Tsuga dumosa)种群为对象, 对开花、结实植株(24个样株)的生长量进行测定, 并采用标准枝法对不同树冠层次与方位的开花及结实数量进行调查, 研究了开花结实规律和对其有主要影响的环境因子。结果表明: 云南铁杉雌、雄球花比为1:2, 雌球花转化为果实的数量仅占28%, 胸径为7 cm (树龄约25年)的植株最早进入开花结实阶段, 胸径为25-30 cm的植株开花结实量最高, 胸径为89 cm (树龄约200年)的植株开花结实最晚; 树冠不同层次与方位上开花结实数量有着明显的差异; 相关性分析得出植株胸径与开花结实量极显著相关(p < 0.01)、与冠幅显著相关, 生境中林分郁闭度与开花结实量、株高、胸径之间均呈负相关关系, 其中与结实量的相关性达显著水平; 主成分分析得出植株开花及结实主要受到温度因子、水分因子、光照因子协同作用的影响。云南铁杉雌雄球花的比例偏雄性、结实周期长、结实方式不经济、灾害性天气的影响是造成该种群逐渐走向濒危的主要原因。因此, 采用人工促进天然更新、建立母树林和种子园以提高种子的质量, 对云南铁杉种群的恢复和保护具有重要意义。  相似文献   

14.
  • The study of intraspecific seed packaging (i.e. seed size/number strategy) variation across different populations may allow better understanding of the ecological forces that drive seed evolution in plants. Juniperus thurifera (Cupressaceae) provides a good model to study this due to the existence of two subspecies differentiated by phenotypic traits, such as seed size and cone seediness (number of seeds inside a cone), across its range.
  • The aim of this study was to analyse seed packaging (seed mass and cone seediness) variation at different scales (subspecies, populations and individuals) and the relationship between cone and seed traits in European and African J. thurifera populations.
  • After opening more than 5300 cones and measuring 3600 seeds, we found that seed packaging traits followed different patterns of variation. Large‐scale effects (region and population) significantly contributed to cone seediness variance, while most of the seed mass variance occurred within individuals. Seed packaging differed between the two sides of the Mediterranean Sea, with African cones bearing fewer but larger seeds than the European ones. However, no differences in seed mass were found between populations when taking into account cone seediness. Larger cones contained more pulp and seeds and displayed a larger variation in individual seed mass.
  • We validated previous reports on the intraspecific differences in J. thurifera seed packaging, although both subspecies followed the same seed size/number trade‐off. The higher seediness and variation in seed mass found in larger cones reveals that the positive relationship between seed and cone sizes may not be straightforward.We hypothesise that the large variation of seed size found within cones and individuals in J. thurifera, but also in other fleshy‐fruited species, could represent a bet‐hedging strategy for dispersal.
  相似文献   

15.
To understand the influence of seed-cone production on the upper-crown expansion of canopy trees of Abies mariesii Masters, the influence of the annually fluctuating number of seed cones on the terminal-leader length of the main stem and primary branches was analyzed using seed-cone rachises remaining on the terminal leaders of the primary branches. The influence of climatic factors during the period of vegetative-bud growth and shoot elongation was also analyzed. For the upper-crown expansion, factors influencing the number of horizontally elongating branches on the top of the main stem were also examined. According to model fitting, the terminal-leader length of the main stem was negatively influenced by seed-cone production 1 year before shoot elongation. In contrast, the terminal-leader length of the primary branches was not clearly influenced by seed-cone production, but was positively influenced by the mean temperature in September 1 year before shoot elongation and in July in the year of shoot elongation. The number of horizontally elongating branches on the top was positively influenced by the terminal-leader length of the main stem 1 year before horizontal elongation on the top and negatively influenced by seed-cone production 2 years earlier. Thus, in the upper part of the crown, the allocation of photosynthate to seed cones mainly affects the arrangement of needles and seed cones up to the higher positions. This trade-off between seed-cone production and upper-crown expansion influences the canopy shape and reproductive strategy of A. mariesii .  相似文献   

16.
Summary Patterns of distribution of seed cones along the length and around the circumference of shoots were determined for young black spruce [Picea mariana (Mill.) B.S.P.] trees aged 9–17 years. Seed cone production averaged 5, 30, 62, 95, and 112 per tree of ages 9, 11, 13, 15, and 17 years, respectively. Cone distribution was restricted to distal and medial 1-year-old branches at age 9 and spread to distal 3-year-old branches by age 17. Sequentially, shoots of 0–25, 26–100, 101–250, 251–325, and 326–375 mm bore more cones in terminal, distal, medial, proximal, and basal positions along shoots, respectively. The uppermost and longest distal 1-year-old shoots bore most of their cones proximally and medially. On the shortest and innermost proximal order 2 shoots, cones were often terminal. The percentages of cones borne on upper, lower, and each of the two side surfaces of shoots were 31, 22, and 21, respectively, and 5% of the cones were terminal. Cones on lower surfaces were most common on the longest shoots near the apex of trees. Cones on upper surfaces became prevalent downward and outward in the crown. On-shoot positioning therefore varied in a predictable manner with shoot length, and thus with pattern of shoot-length distribution in the crown.  相似文献   

17.
植物挥发性物质对落叶松球果花蝇的驱避效果   总被引:7,自引:0,他引:7  
为研究外源植物挥发性物质对落叶松球果花蝇(Strobilomyia spp.)对寄主定位的干扰作用,在哈尔滨市和大兴安岭加格达奇兴安落叶松(Larix gmelinii)种子园,用松节油、樟脑、丁香油进行了室内生测和林间喷施试验。在室内,球果花蝇对1%松节油的反应率为94.23%,与1%丁香油、3%松节油、20%丁香油相比差异显著;对1%樟脑的反应率为87.92%。球果花蝇对2%丁香油的反应率最低,仅为16.30%。在室内及林间,1%松节油及1%樟脑对球果花蝇都表现为驱避作用。1%松节油及其对照对球果花蝇的驱避效果最好,平均每果虫数较清水对照的3.51分别降低了2.85和2.66,使球果被害率降低了57.0%和46.2%,种子被害率分别降低了24.7%和27.7%。其次是1%脑及其对照,每果虫数较清水对照降低了1.83和1.44个,球果被害率分别降低了9.0%和30.7%,种子被害率分别下降了12.2%和26.9%。1%丁香油对花蝇在室内表现为诱引作用,在林间表现为驱避作用。在喷施3种挥发性物质及其对照后,各个处理的球果挥发性物质主要组分的总量都较清水对照增加,各处理的α-蒎烯相对含量较清水对照大幅度降低,降低幅度在13.56%-24.83%之间;各处理的β-罗勒烯都有不同程度的增加。β-蒎烯、3-蒈烯、月桂烯、水芹烯的相对含量在各处理中升降不一。  相似文献   

18.
The eye of Rhinomugil corsula has a duplex retina differentiated into dorsal and ventral halves, with the ventral retina 116·4 μm thicker than the dorsal retina. The rods of the ventral retina are relatively longer, with longer outer segments. The nuclei of the outer nuclear layer of the dorsal and ventral halves are in four and six to seven rows respectively. The rod outer segment bears a single incision. The mitochondria of cone and rod inner segments has a vitreal-scleral gradient. Single and double cones are present in both halves, with triple cones in the dorsal half only. The outer segments of double cones are equal and united. The single cones have two connecting cilia. The cone cells are arranged in a square mosaic with four double cones and five single cones to each unit in the dorsal half, and in a rhombic pattern in the ventral half.  相似文献   

19.
Genetic gain and the gene diversity of seed crops from clonal seed orchards were formulated considering genetic selection, fertility variation and pollen contamination, and compared for five different management strategies. Genetic response was studied as a function of orchard management tactics. Management variables included the proportion of clones left after genetic thinning and/or selective seed harvesting. Formulae were derived to calculate gene diversity (expressed as group coancestry or status number) based on the sex ratio in an orchard population. The influence of having different sets of clones serving as seed parents, or pollen parents, or as both, was analysed. In addition, the impact on genetic gain and the gene diversity of seed crops was studied quantitatively as a function of the quantity and quality of gene flow from outside the orchard. The negative impact of fertility variation among orchard genotypes on the gene diversity of the seed crop was quantified. Numerical examples were given to illustrate the impact of orchard management alternatives on genetic gain and gene diversity. The formulae and results of this study can be used for identifying favourable alternatives for the management of seed orchards. Received: 16 December 2000 / Accepted: 13 March 2001  相似文献   

20.
Summary Seeds produced under open-pollination were collected from eight natural stands and a plus-tree seed orchard of Douglas-fir. These seeds were germinated and both diploid embryos and haploid gametophytes were analyzed by starch-gel electrophoresis. Eleven variable loci were resolved for both kinds of tissue and used as genetic markers for estimating outcrossing rates. Estimates made with single-locus and multilocus methods both indicated that the proportion of viable embryos resulting from outcrossing is about 0.90 for the natural stands, and for the seed orchard. Comparison of single-locus and multilocus estimates of outcrossing rates indicated that little or no inbreeding other than selfing occurred. Estimated outcrossing rates were higher for seeds from the upper portion of the crown than for seeds from the lower crown. It was also found that some trees selfed at a much higher rate than other trees.  相似文献   

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