secondary xylem

Secondary xylem consists of pitted vessels, parenchyma fibers and rays.

次生木质部由孔纹导管 、 薄壁组织及射线所组成.

The secondary xylem of root is well developed, and there is supernumerary cambium around the vessels.

块根的次生木质部发达, 导管周围存在额外形成层.

The primary xylem of root is diarch, of which developmental process contains primary growth and secondary growth. Secondary growth mainly depends on the activity of the vascular cambium and cork cambium.

其根为二原型，发育过程可分为初生生长和次生生长，成熟根的结构以次生结构为主，次生生长主要依靠维管形成层和木栓形成层的活动来完成。

Eco-anatomy of secondary xylem of Schisandra sphenanthera in Huangshan Mountain, Anhui, China

安徽黄山华中五味子次生木质部的生态解剖

With the progressive development of stem, the activity of vascular cambium began. The fascicular cambium differentiated into secondary xylem and secondary phloem, while the interfascicular cambium only differentiated into wide ray of parenchyma tissue.

随着茎的继续发育，维管形成层开始活动，由束中形成层产生次生韧皮部和次生木质部分子；而束间形成层仅产生薄壁细胞组成宽的射线。

Results: The circular belt of sclereids in the phelloderm, secondary xylem vessel order of the transverse section, and tetrarch of the primary xylem were microscopic characters.

结果：根横切面上栓内层的石细胞环带和次生木质部导管的排列方式、初生木质部为四原型等为显微鉴别特征；

The study on the stem secondary xylem of Symplocos paniculata, reveals the wood belongs to diffuse-porous wood.

研究白檀茎次生木质部结构研究，其为散孔材。

While for older roots, there are periderm, secondary phloem, cambium, secondary xylem and primary xylem. In root, the duct caliber of xylem in Akebia quinata ( Thunb.) Decne.

老根由外向内依次为：周皮、次生韧皮部、形成层、次生木质部、初生木质部。在根中五叶木通木质部导管口径比三叶木通的大很多。

Isolating the stem secondary xylem of the seedling, the results revealed that its cellular form have wood fiber, septate wood fiber and vessel element, there are two types of perforation plate, simple perforation plate and scalariform perforation plate.

离析实生苗茎次生木质部，发现其细胞组成有木纤维、分隔木纤维和导管分子，导管分子穿孔板有单穿孔板和梯状穿孔板。

Conclusions The secondary structure of the root of Taxus chinensis var. mairei accords with that of other gymnosperms and dicotyledons, although its secondary xylem is constituted with tracheids and sieve cells.

结论南方红豆杉根的次生构造与其他裸子植物和双子叶植物一致，但次生木质部由管胞，次生韧皮部由筛胞组成。

Structures of the stem secondary xylem of Symplocos paniculata

白檀茎次生木质部结构研究

The present results indicated the remarkable impact of salt stress on cambium cell activity and secondary xylem cell differentiation of both root and stem.

显微结构观测表明，盐胁迫对根和茎形成层细胞的活动和次生韧皮部和木质部细胞的分化产生显著影响。

There are plenty of wood parenchyma in the secondary xylem, most of them are paratracheal parenchyma, belong to the aliform paratracheal parenchyma and vasicentric paratracheal parenchyma;

导管具单穿孔板，轴向木薄壁组织丰富，傍管型居多，为翼状傍管薄壁组织和环管薄壁组织；