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1.
马尾松主要器官树脂道的发生和发育   总被引:3,自引:0,他引:3  
利用半薄切片、超薄切片方法研究马尾松主要器官中树脂道的结构、分布、发生和发育过程,以及树脂道发育过程中的超微结构变化.结果表明:马尾松树脂道是由一层上皮细胞围绕着伸长的胞间道而构成的,上皮细胞外又有1-2层鞘细胞.树脂道几乎分布于所有器官中,仅子叶中未观察到树脂道.树脂道以裂生方式形成,其发育过程可分为3个阶段:原始细胞阶段、形成阶段和成熟阶段.在原始细胞阶段,原始细胞中含较多的质体,质体中缺乏完整的膜结构,在质体外膜及内质网上可见到少量嗜锇滴.在形成阶段,上皮细胞内质体数量增多,质体外常见到内质网鞘包裹,各种细胞器的数量增加.在成熟阶段,上皮细胞内各细胞器的数量逐渐减少,但质体仍很多,嗜锇滴多.  相似文献   

2.
利用电子显微技术对湿地松针叶树脂道的发育进行研究 ,结果发现湿地松针叶树脂道发育过程中有明显分化的三个阶段 :1)树脂道原始细胞阶段 ;2 )胞间层膨大和胞间隙出现阶段 ;3)腔道扩大和树脂道形成阶段 .在这三个发育阶段中 ,树脂道细胞中的各种细胞器呈现不同的超微结构特征及变化规律 ,尤以质体的变化最为显著 .通过分析发育过程中的超微结构特征及其变化 ,探讨了湿地松针叶树脂道发生的方式、树脂合成的场所以及树脂分泌的途径与方式  相似文献   

3.
研究了杉木幼胚发育过程中正常胚和败育胚的淀粉动态,分析了胚败育的原因。在发育正常的种子中,淀粉粒主要分布于胚体及其周围细胞中。在发育不正常的种子中,存在两种情况:1.胚自身的败育:在胚及胚柄系统中无淀粉颗粒分布,雌配子体中有或没有淀粉粒存在;2.雌配子体的败育:最初,胚系统发育正常,淀粉粒的分布与正常胚中一样:雌配子体中存在淀粉层;随着雌配子体细胞从边缘向中心萎缩区域的不断扩大,淀粉区消失,雌配子体死亡,最终导致胚的败育。前一种情况可能起因子自交衰退;后一种情况则可能是导致杉木涩粒形成的胚胎学原因。  相似文献   

4.
为了更准确地确定高产脂思茅松优良种源的选择指标,本研究对高产脂和低产脂的思茅松木质部进行解剖构造观察,并进一步探讨胸径与产脂量之间的关系。结果显示:高产脂思茅松的单个轴向树脂道面积、轴向树脂道密度、径向树脂道密度、径向树脂道直径均显著高于低产脂。高产脂木质部木射线分布密度和高度也高于低产脂思茅松。当思茅松受到外界机械刺激后,高产脂新生轴向树脂道的增长数量明显多于低产脂,同时,该生长轮中的晚材率也高于低产脂思茅松。在实验样地划分的5个小区中,只有第2小区思茅松的胸径与产脂量呈正相关性关系,其余4个小区均不存在相关性。结果表明:木质部单个轴向树脂道面积、轴向树脂道密度、径向树脂道密度、径向树脂道直径、木射线密度和木射线高度均可作为高产脂种质选育的有效参考指标;受到外界刺激后新生树脂道数量和晚材率的变化也可以作为高产脂种质选育的重要参考指标。  相似文献   

5.
【目的】研究毛竹材细胞壁纹孔的形态、结构和分布排列等特征,揭示维管束组织细胞间的纹孔通道,为竹子生长发育机制的深入研究和竹材高效利用提供理论依据。【方法】毛竹竹条经树脂渗透、树脂固化、组织消化和清洗干燥等处理后,获得单个细胞铸型和空间范围内多个细胞连接的立体铸型网络。结合毛竹切片扫描电镜图像,研究导管、薄壁细胞和纤维细胞的纹孔特征以及细胞间纹孔对的连接和分布特点。【结果】毛竹后生木质导管纹孔具明显的纹孔缘结构,并呈较高的选择性分布,即靠近维管束几何中心位置一侧的导管壁上往往密集分布大量纹孔,而另一侧纹孔则十分稀少或基本没有。导管铸型上,纹孔口和纹孔膜分别为0. 9~2. 7μm和1. 1~3. 8μm;维管束内存在小导管且相互间以具缘纹孔对连接;维管束内薄壁细胞纹孔比基本组织中的数量多、孔径大,紧邻木质部导管的薄壁细胞,其纹孔分布尤为密集;纤维细胞上纹孔稀疏分布,纹孔小、纹孔道狭长,纤维状管胞上分布有具缘纹孔;维管束内细胞间由纹孔对进行横向和纵向连接,并进一步形成流体移动的空间网络。【结论】树脂铸型法可直接展现纹孔立体结构,客观反映特定流体在竹材内部的扩散或渗透路径,适用于毛竹材细胞壁纹孔特征的研究。  相似文献   

6.
不同产脂量云南松树脂道解剖学比较研究   总被引:1,自引:0,他引:1       下载免费PDF全文
为确定高产脂云南松的早期选择指标,采用石蜡切片法对不同海拔、不同产脂量云南松的针叶、树干韧皮部和木质部的组成性树脂道特征进行解剖观察,结果表明:高产脂与低产脂云南松的针叶树脂道个数、树干木质部树脂道密度、韧皮部树脂道大小及单位长度树脂道数量存在极显著差异(P<0.01),但不同海拔之间无显著差异;高、低海拔高产脂云南松针叶树脂道数量分别比低产脂的高38.89%、30.34%,树干木质部树脂道密度分别高58.06%、48.48%,韧皮部树脂道大小分别高32.20%、29.73%,韧皮部单位长度树脂道数量分别高21.95%、38.51%.说明针叶树脂道数量、树干木质部树脂道密度及韧皮部树脂道大小3项指标,也可作为云南松产脂力评价的部分指标.  相似文献   

7.
高、低产脂思茅松树脂道的解剖学比较   总被引:2,自引:0,他引:2  
通过对比观察高、低产脂思茅松枝干、针叶树脂道直径、外鞘细胞和分泌细胞个数及树脂道的数目,结果显示高产脂枝干中的树脂道个数和分泌细胞个数明显高于低产脂;并且产脂力系数越大,其树脂道数目和分泌细胞个数也最多,反之亦然。这说明树脂道的数目和分泌细胞数目,尤其是树脂道的数量决定了产脂力的大小,而树脂道的大小和外鞘细胞数目对其产脂力影响并不大。因此,以树脂道数量作为一个重要的指标衡量产脂力,对于高产脂类型思茅松的早期选育具有重要价值。  相似文献   

8.
油樟油细胞和粘液细胞发育的超微结构   总被引:1,自引:0,他引:1  
利用超薄切片法和透射电镜研究油樟油细胞和粘液细胞发育过程。依据油细胞3层细胞壁的发育将其分为4个阶段。阶段1:仅有初生纤维素壁层,又可分为原始细胞和细胞液泡化二时期。质体内具白色小泡和黑色嗜饿滴,细胞质中有黑色或灰色的嗜饿物质,以及嗜饿物质与液泡的融合。阶段2:栓质化壁层的形成。片层状的栓质叠加在初生纤维素壁内侧。阶段3:内纤维素壁层的形成。较厚而结构松散的内纤维素壁层逐步形成,并叠加在栓质化壁层的内侧,大液泡成为充满嗜饿油脂的油囊。阶段4:油细胞成熟及细胞质解体。杯形构造由内纤维素壁层向细胞腔内突起形成,油囊由液泡包被连接到杯形构造中。解体的细胞质变得电子不透明或呈杂乱状态。粘液细胞发育方式有两种:一种是由内纤维素形成以后的油细胞发育而来,其细胞质中不断产生以同心圆或螺旋线方式排列的多膜结构,并充满整个细胞腔,最后多膜结构解体而成为丝状或颗粒状的粘液;另一种是由已完全成熟的油细胞发育而来,其油囊中的油呈不均匀的状态,并产生局部降解点,逐步扩大,最后油完全降解成颗粒成或丝状的粘液。  相似文献   

9.
油杉花粉个体发育中淀粉粒消长变化研究   总被引:1,自引:0,他引:1       下载免费PDF全文
对油杉小孢子发生、花粉形成和花粉萌发过程中淀粉粒的消长动态作了详细观察。油杉于1月后旬形成花粉母细胞,2月上旬完成减数分裂形成小孢子,小孢子经过连续4次有丝分裂后于2月底形成5-细胞型的成熟花粉粒,3月初油杉开始传粉。油杉花粉个体发育中淀粉粒有明显的消长规律,存在2次淀粉粒积累高峰:一次是花粉母细胞进入减数分裂之前,另一次是小孢子进行有丝分裂之前。花粉个体发育中淀粉粒的分布也具规律性:在减Ⅰ中期淀粉粒逐渐呈赤道区聚积,在减Ⅰ后期淀粉粒均匀地移向二子核周围,最终淀粉粒平均分配在4个子细胞内;花粉成熟发育期间,淀粉粒聚集在核的周围,散粉前一天成熟花粉中的淀粉粒全部消失,初步鉴定认为,淀粉粒转变为脂肪。在花粉萌发实验中,淀粉粒重新在其花粉管中出现。初步认为,成熟花粉粒中是否积累有淀粉粒并没有系统发育意义,仅是一种传粉生物学特性之一。  相似文献   

10.
大孔吸附树脂对杜仲叶中绿原酸、总黄酮的分离研究   总被引:17,自引:1,他引:17  
通过对静态吸附容量和洗脱效果的选择,从10种大孔吸附树脂中确定出最适于杜仲叶中绿原酸、总黄酮分离的XDA-5树脂。研究了用该树脂吸附分离杜仲叶中绿原酸和总黄酮的方法,得出以下结论:1)杜仲叶绿原酸和总黄酮的最佳分离工艺为:上柱液pH值为2-3,静态吸附时间8h,绿原酸最佳洗脱剂为10%~15%乙醇溶液,黄酮洗脱剂为50%-70%乙醇溶液,流速为每分钟流出液体积相当于吸附剂体积的8%;2)10%~15%乙醇洗脱液经真空浓缩后,其固形物得率为4.85%,绿原酸含量为36.65%;3)50%~70%乙醇洗脱液经真空浓缩后,其固形物得率为4.98%,总黄酮含量为28.34%。  相似文献   

11.
The structure, distribution and patterns of resin ducts in processes of its initiation and development were studied with the methods of thin section and ultrathin section. This paper emphasized the ultrastructural changes during canal development by a ring of the live epithelial cells, and the epithelial cells were usually surrounded with one or two layered sheath cells, which were normal parenchyma cells in some primary resin ducts and became dead cells with thick walls in other primary and secondary resin ducts. The resin ducts were found to occur in almost all organs, except in cotyledon. The resin ducts were formed by schizogeny and their development can be divided into three stages (e.g., initial stage, formation stage and mature stage). At the initial stage, the initial cells had many plastids without integral membrane structures, which contain one or two starch grains in them, and there are a few black osmiophilic droplets on the endoplasmic reticulum and membranes. A small number of osmiophilic droplets were present in the plastids. At the formation stage, the number of plastids, mitochondria and Golgi bodies in epithelial cells increased. The plastids were commonly surrounded by endoplasmic reticulum sheath. The larger osmiophilic droplets in cytoplasm and the smaller osmiophilic droplets on the plastids envelope, mitochondrion envelope and Golgi vesicles obviously increased in number during canal developing. At the mature stage, the cytoplasm of epithelial cells became thin with small nucleus. The number of mitochondria and Golgi body decreased, but numerous plastids still existed. Osmiophilic droplets were abundant in epithelial cells as in previous status. Taken together, the structures of plastids in epithelial cells gradually became well developed and the synthesis of resin was remarkably enhanced during resin duct formation and plastids should be the main site for resin synthesis.  相似文献   

12.
The influence of genetic determination and environment on the variability of secondary resin canal traits was investigated on 15–19-year-old Norway spruce (Picea abies (L.) Karst.) clones grown in Lower Austria (Pressbaum and Ulmerfeld) and southern Sweden (Knutstorp and Hermanstorp). Eleven and 20 clones were present on the two Austrian and the two Swedish sites, respectively. The sites differed in their water availability, as indicated by different annual precipitation and soil type. Resin canal traits measured were the number of epithelial cells per canal, the number of resin canals per unit tangential wood surface area, the mean resin canal area and the total resin canal area per unit tangential wood surface area. The latter three traits are known to be related to the constitutive resin flow of Norway spruce.

Environment had an influence on the variability of resin canal traits but the most important factor for the variability was the tree’s genetic disposition. Within countries, clones from the drier sites (Pressbaum and Hermanstorp) showed significantly smaller resin canals. Trees from Pressbaum also had smaller total resin canal areas than trees from Ulmerfeld. The number of epithelial cells and the number of canals did not differ between sites.

Resin canal traits had wide genetic variation and high broad sense heritabilities (H2), with values between 0.28 and 0.82. Highest heritability values were reached for the number of epithelial cells and the number of canals (H2 > 0.8). Genotypic correlations across trials were high for the resin canal traits and approached 1 in both the Austrian and the Swedish trials, indicating that there was little genotype by environment interaction for these traits and thus the ranking of clones was very similar in the different environments.

The number of epithelial cells, the mean area and the total resin canal area showed either moderately significant positive genotypic correlations with tree growth traits or none at all.

In a breeding context, our results are encouraging and indicate that high constitutive defence potential against bark beetles, such as Ips typographus, is not aligned with low volume growth. But it should be taken into consideration that environment and forestry practices can also have an impact on the resin reservoir provided by the radial resin canals.  相似文献   


13.
Seasonal changes in starch were studied at the tissue and cellular levels in roots and stems of Salix viminalis L. cuttings. Cuttings were planted in pots containing sand and grown in a controlled environment chamber in which seasons were artificially induced by changes in temperature and photoperiod. Nitrogen was supplied at optimum and low rates, and during dormancy, one-half of the plants were decapitated. Starch concentrations in root and stem tissues were determined regularly during shoot extension growth, dormancy and resprouting after dormancy. We used light microscopy (LM) combined with image analysis (IA) to determine the cellular localization and amount of starch in different cell types of stem and root tissues. Chemical analysis confirmed that starch concentrations were lower in plants receiving a high-N supply rate than in plants receiving a low-N supply rate. In all plants, the highest concentration of starch was in the roots. Light microscopy and IA showed that starch accumulated mainly in the phloem and cortical cells of both root and stem tissues. Starch grains were also regularly found in ray parenchyma cells. The amount of starch as well as the size of the grains showed strong seasonal fluctuations. In both roots and stems, starch concentrations were highest during predormancy and lowest during periods of shoot extension growth. At the time of resprouting, root cells of decapitated plants were more depleted of starch than root cells of intact plants, supporting the hypothesis that starch reserves in roots are important during the early phase of resprouting in coppice systems.  相似文献   

14.
马尾松泌脂系统树脂道结构电镜扫描   总被引:2,自引:0,他引:2  
  相似文献   

15.
Structural changes in cells affected by the fungus C. fimbriata, involving the cell wall, cytoplasm and plastids were investigated. In the necrotic tissues a high number of fat drops was observed. The progress of hyphae of the fungus in poplar clones differing in their resistance depended on the presence of a cork layer, tannins and starch content.  相似文献   

16.
中间试验规模为小试规模的667倍(0.5吨/锅)。采用常压与减压相结合、回收丁醇直接循环使用的一步法合成工艺,验证了工艺条件的稳定性;考核了选用的生产装置的适用性和生产规模的技术、经济可行性。实验结果表明:工艺完善,设备合理,产品技术性能稳定,可代替40—50%的紫胶。改性紫胶价格仅为普通紫胶价格的60%,技术经济效益良好,可按中试规模或进一步扩大规模实施生产。  相似文献   

17.
沙冬青叶片结构特征及其与抗寒性的关系   总被引:10,自引:0,他引:10  
韩善华  李劲松 《林业科学》1992,28(3):198-201,T002
沙冬青叶片上的表皮毛密集,角质层很厚,表皮细胞连接紧密,栅栏组织特别发达,海绵组织很少。在栅栏组织细胞中,液泡膜大量内陷,在液泡中形成各种膜状结构,有的还与附近的细胞质,乃至小泡和内质网一起内陷,形成细胞质突起,进而形成细胞质带,不断分割液泡,使液泡体积越来越小,数量越来越多,分数度大大提高。在这些小液泡中,颗粒状和纤维状物质十分丰富,但一般很少有大量的膜状结构。  相似文献   

18.
BLS-水溶性油墨应用了作者研制的、能长期贮存的改性漂白紫胶树脂。油墨由紫胶树脂、水性丙烯酸树适当的有机颜料、溶剂、助剂元首与制而成,具有良好的流动性,贮存稳定性、干燥性、耐水性及印刷适应性;使用中返溶性好,泡沫少、清洗方便;最终印件清晰、饱满、附着力强,因使用无毒树和溶剂而无环境污染,安全可靠。  相似文献   

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