根系

Under certain conditions, the activation and migration of soil Cd were accelerated by the interaction of Pb and Cd and increased Cd uptake by wetland rice. The organic-bound Cd in rizhosphere decreased by 90%. These phenomena illustrates that the interaction is very important for the transformation of soil Cd fractions. Meanwhile, the interaction distinctly affected the composition of roots secretion and their coordination abilities with heavy metals, causing clear variation to Cd amount in root cortex and middle columniation.

在一定的实验条件下，Pb和Cd的交互作用促进了Cd的活化与迁移，增加了水稻地上部分对Cd的吸收，使根际土有机结合态Cd下降了90%左右，表明交互作用对Cd形态的转化是一个重要的控制因素；同时交互作用对根系分泌物的组成及其与重金属的配位能力有着明显的影响，使Pb、Cd在根系皮层和中柱中Cd的含量有明显变化。

Secondly, through on-site and laboratory testing, studies the impact of root distribution density and distribution methods to root complex shear strength.

根系的抗拉特性符合一定的规律，对进一步研究根系的拉拔特性奠定基础。

But the content of MDA in leaf and root was not decreased on the contrary it was increased. It indicates that the damage of Plasma membrane in maize leaf and root have more complex mechanism.

但此时叶片和根系中MDA的含量并没有下降，反而增加，说明玉米叶片和根系组织的膜伤害有更复杂的机理。

The results showed:(1) the propagation coefficient were from 0.8 to 6.8 in different development phase, the highest propagation coefficient appeared in June, July in dormancy stage and September in initial stage of vigorous growth;(2) all of biological characters, such as cormel's fresh weight, size, height, root length, roughness and root quantities, presented 1% significant difference.

结果表明：(1)不同生长发育期无性繁殖系数在0.80~6.80之间浮动，休眠期的6、7月和旺盛生长初期的9月繁殖系数较高；(2)不同生长发育期无性繁殖的子球鲜质量、最大直径、子球高度、根系长度、根基粗度及根系数量等生物学性状均呈现1%水平极显著差异。

Soil with 1.2 g/cm3 bulk density was most favorable for the plant height and root growth of cucumber plants,and soil with 1.4 g/cm3 bulk density was most favorable for the stem thickness,yield and nutrient uptake of cucumber plants under this experiment conditions.

在本试验条件下，容重为1.2.g/cm3的土壤利于株高及根系的生长，容重1.4g/cm3的土壤则利于茎粗、根系养分的吸收及产量的增加。

But systematic research concerning continuous mono-cropping grafted cucumber obstacle isn't reported. This paper systematically studied the effect of continuous cropping soil on grafted cucumber in aspect of its growth, yield and edaphon in pot experiments. Further more, root exudates of squash and grafted cucumber were collected by solution cultivate and adsorption of XAD-4 resins, and bioassay of the root exudates was did with cucumber and squash as receptors, studied allelopathy of grafted cucumber and squash root exudates on cucumber and squash , physiobiochemistry as well as.

本项研究采用盆栽试验以不同连作年限的土壤为基质比较系统地研究了连作年限对嫁接黄瓜的生长、产量和土壤微生物的影响；采用水培和XAD-4树脂吸附法分别收集嫁接黄瓜和砧木南瓜的根系分泌物并以黄瓜、南瓜为受体进行生物活性测定，并对嫁接黄瓜及其砧木南瓜根系分泌物化感作用的生理机制进行了初步探索。

The results showed that the wheat growth was increased with lower concentration of Cu; but with higher concentration of Cu, the activities of diastase and the mitotic index of root tip cell of wheat were reduced, the content of pro was increased.

朱云集等研究了Cu对小麦根系生长发育及生理特性的影响，指出随Cu浓度的提高，小麦胚根、次生根条数减少，根系SOD与POD活性呈下降趋势[7]。

Therefore, the relation between dripper discharge and crop-root distribution is the basis for determining technique parameters of drip irrigation.

土壤湿润区与作物根系分布之间的关系是确定滴灌湿润比的理论依据，而土壤湿润区形状直接受滴头流量的控制，因此，滴头流量与作物根系分布之间的关系是确定滴灌技术参数的依据。

Based on the pot culture experiments, cotton root structure and distribution were measured in seedling stage, bud stage, flowering stage, boll stage, and boll opening stage with the dripper discharge of

该文以桶栽试验为基础，设置5个滴头流量处理（0.5、1、1.5、2、2.5 L/h）观测了棉花5个生育阶段（苗期、蕾期、花期、铃期、吐絮期）的根系结构和根系分布。

The total length of roots in a 120cm wide and 90cm deep soil profile is 98714.8cm, which can enlace soil about 235 circles. The average diameter of eulaliopsis binata Retz.

在120cm×90cm土体内，蓑草根系总长98714.8cm，相当于缠绕整个土体235圈，正是根系的这种缠绕固结作用显著提高了土壤抗侵蚀的能力。

Fancy gold-plated dangling earrings with facetted White Opal crystals.

花式镀金悬垂耳环与facetted白欧泊水晶。

This essay chooses the study aim from biology teachers in middle school in Shi Jiazhuang which tells us that most of the middle school biology teachers in Shi Jiazhuang have the"burnout", lower successfulness, individualize.

本文选取石家庄市初中生物教师作为研究对象，运用问卷调查的方法对石家庄市初中生物教师职业倦怠的现状进行调查，调查结果发现，石家庄市初中生物教师这一群体普遍存在职业倦怠，情感枯竭程度偏高，成就感偏低，去个性化程度最为严重。