维管形成层

维管形成层发生和活动的机理

The mechanism for the initiation and activity of vascular cambium

次生生长主要是依靠维管形成层和木栓形成层的活动来完成。

The secondary growth mainly relied on activities of vascular cambium and cork cambium .

维管形成层位于木韧之间。

The vascular cambium is located between the xylem and the phloem .

杉木维管形成层发生发育的解剖学观察

Anatomical Observation on Development of Cambium in Cunninghamia lanceolata

维管形成层已经形成，但次生结构尚不发达。

Vascular cambium has formed , but the secondary structure is far from developed .

分析此现象可能与维管形成层细胞的分裂分化作用有关。

It was analysed that the phenomenon was related to the divide and differentiate of vascular cambium cell .

维管形成层细胞分裂后，在内侧分裂出来的细胞成为木质部的母细胞。

After vascular cambium cells divide , the progeny cells on the interior side become xylem parental cell .

漆树茎干维管形成层的活动有明显的季节性，冬季休眠，春、夏季细胞分裂活动。

Cambium activity has obvious seasonal variations , vascular cambium dormant in the winter and active in spring and summer .

同时，运用石蜡切片法研究剥皮后愈伤组织的形成、木栓形成层和维管形成层的发生；

Meanwhile , paraffin-cut section method was used for studying on callus formation , cork cambium and vascular cambium initiation .

束中形成层：是位于木质部和韧皮部构成的维管束内的一部分维管形成层。

Intrafascicular cambium ( fascicular cambium ) The part of the VASCULAR CAMBIUM within the vascular between the xylem and phloem .

20天左右在与愈伤组织接触的木质部细胞发生维管形成层。

Approximately 20 days later , the immature xylem cells differentiated vascular cambium cells at the place where callus bound xylem .

从横切面上观察到，不定根原基起源于髓射线与维管形成层交叉的部位。

From cross sections of stems-cuttings , a primordium of adventitious roots originates from the cross region of pith rays and vascular cambium .

维管形成层木质部母细胞进一步分化形成导管、胶质纤维、韧型纤维和木薄壁细胞。

The secondany xylem mother cell of vascular cambium were differentiated into vessels , gelatinous fibre , libriform fibre , and parenchyma cell .

木材的形成是一个非常复杂的生物学过程，是众多树木基因在维管形成层活动中有序表达的结果。

Wood formation is a complex process involving many genes expressed coordinately in the different developmental stages of secondary vascular system ( SVS ) .

美洲黑杨维管形成层活动周期可分为休眠期、恢复活动期、活动期和转化期4个时期。

The periodicity of vascular cambial activity in Populus deltoides could be divided into four stages : dormant , renewed active , active and transformed stages .

不定根的形成可以产生在插入苗床的枝段各个部位，以基部1&3节最多，主要由维管形成层细胞或韧皮部薄壁细胞分裂产生。

Adventitious roots cood be produced in every position of the branches inserted in the seedbed , most of which distributed in 1 & 3 node of base .

其次，缺钾可能影响茎中木栓形成层的正常发生，以及影响维管形成层的细胞分裂活动，并可能干扰韧皮部纤维的正常发育。

Secondly , It may effected the normal formation of phellogen and the mitosis of cambium in stem , as well as the normal development of phloem fibers .

但是当维管形成层形成时，束间形成层在初生乳管的近轴一侧产生，因而随着次生形成层的活动，初生乳管被定位于次生韧皮部远轴一侧。

As the vascular cambium was initiated , the interfascicular cambium was formed on the adaxial side of secondary phloem produced by the cambium . phloem developed well ;

初生木质部与初生韧皮部之间可见到2&3层排列规则或不规则的薄壁组织细胞，但是没有维管形成层的发生。

Between primary xylem and primary phloem there are 2 & 3 layers of parenchymatous cells , regularly or irregularly arranged , but no cambial zone can be recogni - zed .

但在以后的发育过程中，木栓形成层产生了多层栓内层薄壁细胞，维管形成层则产生了大量高度薄壁组织化的次生维管组织，从而形成了肉质膨大的块根。

The main cause of root tuber expanding is that phellogen produces many layers of phelloderm parenchyma cells and vascular cambium produces a lot of secondary vascular tissue that consists of parenchyma .

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。

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 .

研究结果表明：（1）巴西橡胶树茎干小面积剥皮后，新皮再生经过愈伤组织形成和维管形成层发生2个阶段。

After a piece of bark ( 2.5 cm × 2.5 cm ) was stripped from the Hevea stem , the new bark regeneration involved two stages : the callus formation and vascular cambium initiation .

愈伤组织由靠近伤口表面未成熟的本薄壁组织细胞和木射线细胞分裂产生，维管形成层在愈伤组织内层发生，且是一个渐进的过程。

The callus started to produce near the surface of the wound from the remaining immature xylem cells including xylem parenchyma cells and xylem ray parenchyma cells , and the vascular cambium was gradually initiated within the callus .

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。

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 .

豫楸1号不定根源于皮层细胞和维管形成层细胞，根原基原始细胞进一步分裂、分化形成不定根。

Catalpa bungei Yu Qiu No.1 the adventitious root primordium from the cerebral cortex parenchyma cells and the vascular bundle cells . the root primordium cells further splits , the differentiation to form the adventitious root . 5 .

剥皮后组织分化特点：黄柏剥皮时绝大部分维管形成层细胞已随皮层剥离树干，树干表面仅由未成熟的木质部细胞和木质部射线细胞组成，部分部位仍残留有形成层细胞。

The trait of organize differentiation : During girdling most of vascular cambium cells were stripped from the stem . Then immature xylem cells and ray cells were composed of the barked surface , and vascular cambium cells in part portion were remained .

维管形成层韧皮部母细胞分裂分化形成筛管、伴胞、韧皮薄壁细胞、韧皮纤维和少量的石细胞，筛管和伴胞来源于筛管母细胞的不均等有丝分裂。

The secondary phloem mother cell were divided and differentiated into sieve tube , companion cell , libriform fibre , parenchyma cell , and a few sclereid cells , The sieve tube and companion cell was originated from inequality mitosis of sieve mother cell .

它们分别发育转化为维管形成层中的纺锤状原始细胞和射线原始细胞.结果表明：①掌叶木种群径级和高度结构呈纺锤状，为衰退型种群。

At the early stage of primary growth , there are two types of cells in the vascular meristems , one is longer and the other is shorter . All results indicate : ( 1 ) The structure of diameter and height shows spindle shape belonging to decline population .

组织学观察显示，魔芋叶柄无维管组织形成层，维管束外层薄壁在培养过程首先启动脱分化，进而形成愈伤组织。

Histological observations showed that cambium was absent in konjac petiole and that the cells outside vascular bundles of petiole firstly started dedifferentiation division to form callus .

到雌雄蕊分化期，穗、茎维管系统依靠原形成层束达到初步联络；

By the time of differentiation of the primordia of stamen and pistil , the bundles of the ear and the stem were connected through procambium .