查询词典 embryogenesis

B Of the six basic media MS, MS1/2 (half-strength of MS salts and vitamins), WPM, DKW, B5 and SH, MS1/2 was the most proper one to induce somatic embryos. Somatic embryos generally regenerated directly from excised zygotic cotyledons. PGRs combination affected somatic embryogenesis significantly. Medium with NAA 1mg/L, TDZ 0.05mg/L, IBA 2—10mg/L combined with BA 10mg/L, or IBA 10mg/L integrated with BA 0-2mg/L gave the highest induction rate. Excised zygotic hypocotyls had the strongest potential to produce callus. Callus induction was also affected significantly by media and PGRs. The proper callus induction condition was MS1/2 medium containing NAA 1mg/L, IBA 10mg/L, BA 2-5mg/L and TDZ 0.05mg/L. Harvest period affect somatic embryogenesis significantly. Zygotic embryo explants collected from the end of July to the middle of August had strong potential to generate somatic embryos, when endosperm finished solidification, different parts of the embryos were completely formed, the size of embryos occupied about 2/3 of the embryo sac. Provided with optimized conditions, direct somatic embryogenesis rate can attain to 33. 68%, and callus induction rate of hypocotyls was up to 90.7%. Cytological observation on megasporogenesis and zygotic embryogenesis of Manchurian ash showed that the ovary was twicarpellum, twilocular with two ovules each loculus. The ovule was tenuinucellar and anatropous, with one megasporcocyte. The development of embryo sac is of the Polygoum type.

体细胞胚胎发生研究的结果表明：(1)成熟过程中的合子胚是诱导水曲柳体细胞胚胎发生的最佳外植体材料；(2)在所试验到的MS、MS1/2（将MS的所有成分均减半）、WPM、DKW、B〓、SH等六种基本培养基中，MS1/2是最适合诱导水曲柳体细胞胚胎发生的基本培养基；(3)水曲柳的体细胞胚胎发生以直接发生为主，体细胞胚主要来自于从合子胚分离的完整子叶；(4)培养基中的激素组合对水曲柳的体细胞胚胎发生有显著影响，诱导直接体细胞胚发生较好的激素组合有NAA 1mg/L+IBA 2，5，10mg/L+BA 10mg/L+TDZ 0.05mg/L和NAA 1mg/L+IBA 10mg/L+BA 0，2mg/L+TDZ 0.05mg/L；(5)合子胚分离的下胚轴具有最强的愈伤组织诱导潜力，少数愈伤组织可以分化出体细胞胚；(6)愈伤组织的诱导也受培养基和激素配比的显著影响，最适宜诱导的培养条件为MS1/2+NAA 1mg/L+IBA 10mg/L+BA 2，5mg/L+TDZ0.05mg/L；(7)采种时间对体细胞胚胎发生有显著影响。7月末到8月中旬的合子胚具有较强的体细胞胚发生潜力，此时种子尚未成熟，胚乳已呈固态，种胚的各个部分已分化完全，种胚体积占胚腔的大约2/3；(8)在各自综合的最适条件下，完整子叶的体细胞胚诱导率可达33.68%，下胚轴的愈伤组织诱导率可达90.7%。

In this study, the peanut (Arachis hypogaea L.) cultivars were used as materials to investigate the effect of 2,4-dichlorophenoxyacetic acid(2,4-D) on somatic embryogenesis and of naphthaleneacetic acid and ascorbic acid on rooting, then to find a efficient protocols for regeneration of plantlet via somatic embryogenesis.

本试验以落花生栽培种之未熟胚为材料，探讨2，4-dichlorophenoxyacetic acid(2，4-D)诱导体胚，及naphthaleneacetic acid与抗坏血酸促进发根的效果，期望建立经由体胚形成再生植株之方法。

Temporal and spatial expression pattern of gibel carp pou2 during embryogenesis was investigated by RT-PCR and whole-mount in situ hybridization. RT-PCR result indicates that there is maternal transcript of gibel carp pou2 in early embryos and the zygotic pou2 transcript is abundantly expressed from blastula stage. Large amount of pou2 transcript is detected at both 50% and 90% epiboly stages. At 100% epiboly stage, however, the pou2 transcript reduces rapidly and disappears at the later embryogenesis. Whole-mount in situ hybridization shows that the maternal transcript ubiquitously exists in all blastomere cells.

我们用RT-PCR和整体原位杂交的方法研究了银鲫pou2基因在胚胎发育过程中的时空表达图式RT-PCR结果显示，银鲫pou2基因有母源转录本，其合子基因在高囊胚期强烈表达，在50%下包期和90%下包期也有高量的转录本，但在100%下包期表达量急剧降低，至体节期时已经完全检测不到其转录本胚胎整体原位杂交结果显示其母源转录本在所有的胚盘细胞中。

The expression pattern of gibel carp pou2 suggests that this gene should play an important role during early stages of embryogenesis. It might regulate the formation of neural plate and the fate of midbrain and hindbrain cells during early embryogenesis.

银鲫pou2基因的表达图式提示该基因在胚胎发育的早期具有重要作用，它可能参与调控神经板的形成和中后脑细胞的发育命运。

Ginseng can be regenerated through organogenesis or somatic embryogenesis and indirect somatic embryogenesis is mainly used for its regeneration.

遗传改良是人参育种的重要手段之一，而遗传转化和再生体系的建立是开展人参遗传改良工作的前提和基础。

Some key developmental events of embryogenesis, such as directional expansion, asymmetrical first division, suspensor formation and degeneration as well as embryo differentiation, occurred as that in in planta embryogenesis in the experimental condition.

追踪观察表明，合子体外胚胎发生过程中关键发育事件，如合子休眠期间的定向生长、一次不对称分裂的完成、胚柄的形成和解体、胚的分化等过程均可在体外重现。

The frequency of somatic embryogenesis was less than 20%, which showed that somatic embryogenesis of Medicago truncatula is genotype-dependent.

由胚性愈伤诱导体胚的发生率低于20%，表明品种的基因型在很大程度上影响Medcago truncatula体胚的发生率。

The effect of ABA on embryogenesis of Physalis pubescens L. and the possible relationship between somatic embryogenesis and environment stress were also discussed.

进步讨论了ABA对毛酸浆体细胞胚发生的影响以及体细胞胚发生与环境胁迫的可能关系。

The reseach on activity changes of SOD, POD and CAT during the somatic embryogenesis of Y35 showed:(1) The activty of SOD was from 52.98 to 133.20 U·g-1·h-1, and remained a rising trend after early single embryo forming, this revealed that SOD might be positively correlated to the differentiation of embryogenic cell and the development of somatic embryo.(2) The activty of POD was from 0.05 to 0.50 U·mg-1·min-1, ascended firstly and desceded later, and was highest in embryogenic callus and lowest in late single embryo , this revealed that POD might be positively correlated to the division and differentiation of proembryo mass, while negatively correlated to the development of PEMⅢto late single embryo.(3) The activty of CAT was from 0.86 to 2.81 U·mg-1·min-1, showed an up-down-up trend, reaching to the highest peak at the time of early embryo formating and decreasing to the lowest at the time of early cotyledonary embryo formating, this revealed that CAT might be positively correlated to the development of early single embryo, while negatively correlated to the formation of middle single embryo and early cotyledonary embryo.The changes in activty of SOD, POD and CAT indicated these three antioxidant enzymes coregulated the differentiation and development of embryogenic cells during Larix somatic embryogenesis.4. Differentially expressed cDNA libraries of the stages of proembryo mass and somatic embryo maturation were successfully constructed by suppression subtractive hybridization.

对Y35体细胞胚胎发生过程中抗氧化酶活性变化的研究显示：(1)SOD活性在52.98~133.20 U·g-1·h-1之间，并在早期单胚形成后一直保持上升的趋势，表明其与胚性细胞的分化及体细胞胚的发育均具呈正相关；(2)POD活性在0.05~0.50 U·mg-1·min-1之间，呈现出先下降后升高的趋势，在胚性愈伤组织中最高，而在后期单胚形成时降至最低，表明其与原胚团的分裂和分化呈正相关，但与PEMⅢ向后期单胚的发育呈负相关；(3)CAT活性在0.86~2.81 U·mg-1·min-1之间，表现出升-降-升的变化趋势，在早期单胚形成时升至最高，在早期子叶胚形成时降至最低，表明其与早期单胚的发育呈正相关，而与中期单胚和早期子叶胚的发育呈负相关。

During somatic embryogenesis and zygotic embryos development,the start-up and morphogenesis of embryos are regulated by a variety of factors.In particular,somatic embryogenesis is a temporal and special regulated developmental process.

在体细胞胚胎发生和合子胚发育的过程中，无论是胚胎发生的启动还是胚状体的形态建成都受到多种因子的调控，体细胞胚发生是一个由多种基因参与的复杂时空调节的发育途径。

Bob Eckert has been chairman and chief executive of Mattel for eight years.

美泰董事长兼首席执行官鲍勃·埃克尔特在任已8年。

The outlook for honors and disgraces carries on and surpasses the traditional outlook for honors and disgraces theoretically, and carries on and develops the theory of construction of socialist mora...

社会主义荣辱观的提出在理论上是对传统荣辱观的一次继承和超越，是对社会主义道德建设理论的继承和发展，在实践上有利于形成良好的社会风尚。