生根瘤

ADVANCES OF STUDIES ON BACTEROID REPRODUCTION OF R trifolii Rhizobium leguminosarum , AND FAST GROWING SOYBEAN RHIZOBIUM

三叶草，豌豆和快生型大豆根瘤菌类菌体繁殖研究的进展

To better understand the roles of LsrA protein in nodulation, a series of analyses of nodules using scanning electron microscopy, genetic and biochemical approaches have been carried out. Our analyses suggest that the lsrA1 nodules contain bacteroids in the invasion and establishing zone only. The lsrA gene expression is active early in the invasion zone and activated later than bacA genes. The lost of LsrA protein dramatically reduced the expression of nifA and fixK, and completely blocked the expression of the nifH gene for nitrogenase. LsrA protein functions early in the bacteroid development and it is essential for the development nitrogen fixing bacteroids.

前期的工作中，苜蓿中华根瘤菌Rm1021中90个候选LysR基因已经被定向插入突变，并筛选在自生生长时期、共生生长时期的表型，以期寻找更多在自生状态或共生固氮中有功能的LysR转录因子。1 针对前期鉴定出的共生固氮必需的lsrA基因，我们应用了一系列扫描电子显微镜技术、生物化学、分子遗传学等方法，发现lsrA基因主要在根瘤侵染区开始表达，表达时序也在侵染阶段左右，但晚于bacA基因表达；LsrA蛋白缺失后根瘤固氮区中缺乏具有固氮能力的类菌体，nifA和fixK基因的转录水平降低，nifH基因的转录被完全阻断，因此LsrA蛋白为根瘤发育所必需，是新的根瘤发育信号传导途径成员。2 通过表型筛选我们鉴定了苜蓿中华根瘤菌的oxyR基因，并研究了它的调节特性。oxyR突变后，苜蓿中华根瘤菌对过氧化氢敏感性提高，适应性降低。

Xie Weiji counts a shape compound leaf, flocculus each other is unripe, 11-27 long elliptic or pod of form pouring egg is long and thin if point to shape, 3-12 part grows 2-3 in all centimeter, the section is broken easily, every contain condition of slightness of seed of * of a seed, kidney, black Brown.

有根瘤。叶为奇数羽状复叶，小叶互生，11-27枚长椭圆形或倒卵形荚果细长如指状，3-12节共长2-3厘米，节易断，每节含1粒种子*种子细长。肾状，黑褐色。

The results indicated that the nodule nitrogen fixation activity, nodule and young stem ureide contents were the highest in cultivated soybean and the lowest in wild soybean.

结果表明，根瘤固氮酶活力表现为栽培大豆金元＞半栽培大豆吉50451＞半野生大豆吉50853＞野生大豆生1。

Arcuata; A large quantity of cells in fascicular nodules were infected by rhizobia; 16S rRNA gene sequence of T. arcuata shared the highest identities with that of Sinorhizobium meliloti, and this strain was able to tolerate relatively higher temperature and alkalin.

弯果胡卢巴结瘤需要较好的土壤及通气条件；根瘤簇生，瘤内含大量被根瘤菌侵染的细胞；弯果胡卢巴根瘤菌与苜蓿中华根瘤菌同源性最高，是一类较耐高温和强碱的菌株。

The Frankia-actinorhizal plant root nodule symbiosis occurs in 8 families of angiosperms.

固氮放线菌Frankia是能够诱导大范围的放线菌根植物产生根瘤放线菌。

Root system is sturdy develop, give birth to root nodule closely, the errant bud on its root recovery capability is strong, can make root system spreads to horizontal way.

根系粗壮发达，密生根瘤，其根上的不定芽再生能力强，能使根系向水平方向蔓延。

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。