蕨类植物的木质部只含有管胞。
导管与纤维管胞均具明显的螺纹加厚。
Vessel and fibre - tracheid are both spiral thickening distinctly.
管胞直径、胞壁厚度自髓心向外增加。
The tracheid diameter and the thickness of cell wall increase from pith to bark.
蕨类植物和针叶树的木质部仅含有管胞。
轴向系统由管胞和木薄壁组织细胞组成；
Axial and radial systems formed the secondary xylem of the roots.
研究间歇性淹水对池杉木材管胞形态变异的影响。
The effect of intermittent flood upon the radial variation of tracheid features of Taxodium ascendens was investigated.
环状加厚：原生木质部导管和管胞的内层环状増厚。
Annular thickening rings of thickening laid down on the inner wall of protoxylem vessels and tracheids.
植物的超声发射是导管或管胞里空穴化时的伴随现象。
Ultrasonic emission is a phenomenon with cavitation of vessels or tracheids.
可在原生木质部和初始后生木质部的管胞和导管中见到。
It is found in protoxylem and first metaxylem tracheids and vessels.
对55个杉木无性系管胞微纤丝角的遗传变异进行了研究。
Genetic variations on tracheid microfibril Angle of 55 Chinese fir clones were investigated.
造林密度大，则生长轮变窄，管胞列数减少，晚材率增加。
As planting density increased, the growth ring width and tracheid row decreased but proportion of late wood increased.
管胞长度的种源区和产地效应很小，无一定的地理变异趋势。
There were very small effect of seed source and no definite geographic pattern in tracheid length.
与健康组织相比。其管胞的长、宽和木射线高度均差异显著。
There are significant difference in tracheids' length and width and height of wood ray comparing with healthy tissues.
结果表明，管胞直径和微纤丝角及生长轮宽度等指标表现为差异显著。
The results showed that there were distinct differences in micro-fibril Angle, width of growth-ring and tracheid diameter.
瘤组织中的薄壁细胞均增生肥大，木质部的垂直管胞发生变形且变短。
Parenchyma in gall tissues were observed to occur hypertrophy or hyperplasia, and vertical tracheids in gall xylem were short and abnormal in shape.
家系均值折线图显示，不同地区木材的基本密度、管胞长度层次明显。
The broken - line graph of average values of families show evident differences in wood basic specific gravity and tracheid length between different regions.
薄壁细胞向内生长的泡状物通过纹孔伸入相邻的管胞或导管形成的结构。
Tylose a bladder like ingrowth from a parenchyma cell into an adjacent tracheid or vessel through a paired pit.
影响管胞形态地理变异的气候因子中，水湿条件是主导因素，其次是温度。
Among the climatic factors which affect the geographic variation of tracheid morphological, moisture and rainfall are the principal factors, secondary is temperature.
结果表明，造林密度对马尾松管胞形态总平均值影响不大，方差分析不显著；
The results show that the average value of tracheid form can not be affected by the planting density through variance analysis .
顺纹抗拉强度主要受管胞长度、管胞强度、纤丝角度、结晶度等因子的控制。
Tensile strength is mainly controlled by tracheid length, tracheid strength, microfibril angle and crystalline degree etc.
木质部在维管束植物中的起支撑作用和输水作用的组织，主要由管胞和管道组成；
The supporting and water-conducting tissue of vascular plants, consisting primarily of tracheids and vessels; woody tissue.
所以，10龄被确定为基本密度的最佳选择年龄。管胞长度幼——熟龄相关不稳定。
The optimum selection age of basic density was determined at 10 years, the juvenile-mature correlation in tracheid length was unstable.
结果表明，无性系间树高、胸径、材积、木材基本密度和管胞长度存在显著至极显著差异。
The results indicated that the five traits like height, diameter at breast height, volume, wood basic density and tracheid length showed at least significant genetic variation among clones.
轴向管胞之间、轴向管胞与射线薄壁细胞之间、轴向管胞与射线管胞之间，均有不同类型的纹孔对。
There are different types of pit-pair between the axial tracheids. the axial tracheid and the ray parenchyma, the axial tracheid and the ray tracheid.
轴向管胞之间、轴向管胞与射线薄壁细胞之间、轴向管胞与射线管胞之间，均有不同类型的纹孔对。
There are different types of pit-pair between the axial tracheids. the axial tracheid and the ray parenchyma , the axial tracheid and the ray tracheid.
吸器中管胞和筛管都是从吸器中央具有原形成层特性的细胞分化的，管胞的分化先于筛管，或同时进行。
The tracheid and sieve tube elements are all differentiated from the procambia in the center of the haustoria, and the former occurs prior to the latter.
种源内木材气干密度、力学强度及胞壁率差异不显著，管胞长、宽和壁厚的差异均显著且高于种源间的差异。
Meanwhile, there were not significant differences in wood air dry density, mechanical strength and cell wall percentage of intra provenance.
该文利用原位成像纳米压痕技术研究了针叶材管胞细胞壁不同壁层之间在纵向弹性模量(MOE)和硬度方面的差异。
In situ imaging nanoindentation was used to characterize the differences in longitudinal Modulus of Elasticity (MOE) and hardness of different cell wall layers of softwood tracheids.
采集贵州省龙里林场马尾松密度试验林15年生马尾松木材，5种造林密度，研究造林密度对马尾松管胞形态及其径向变异的影响。
The tracheid form and radial variance were studied for 15 years Masson pine plantations with five different planting densities in Longli, Guizhou.
结果表明：间歇性淹水对池杉木材管胞形态的径向变异规律无影响，即不论有无间歇性淹水，池杉木材管胞长度、直径、壁厚，皆是自髓心向外呈增加趋势。
The results showed: from pith outward, the tracheid length and diameter and cell wall thickness of Taxodium ascendens wood with or without intermittent flood all increased.
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