针叶树体细胞胚胎发生的研究进展

简要回顾了针叶树体细胞胚胎发生的研究历史,并对针叶树体细胞胚发生的基本程序、影响因素及应用前景了综述。     

植物体细胞胚胎发生的诱导与调节研究进展

植物体细胞胚胎发生的诱导与调节研究进展陈以峰（江苏省农科院遗传生理所,南京２１００１４）植物体细胞胚胎发生是一个复杂的发育过程,受到多种内、外因素的影响与调节,研究体细胞胚胎发生诱导与调节既是一个基本的理论问题,更为重要的是,这方面的成果为提高植株再...     

脱落酸与植物体细胞胚胎发生关系的研究进展

简要综述了植物体细胞胚胎发生过程中内源ABA水平及外源ABA对体细胞胚胎发生和发育的调节作用及其作用机制,并提出了未来的研究方向。     

棉花体细胞胚胎发生的研究进展

经过30多年的发展, 已经在多个不同的棉花品种中获得了体细胞胚, 并再生成苗。但由于体细胞胚胎发生往往受多种因素影响, 如何从愈伤组织高效率地转化为胚性愈伤组织依然是限制棉花组织培养与遗传转化的关键问题之一。本文概述了棉花体细胞胚胎发生的研究进展, 分别从棉花体细胞胚胎发生的起源、影响棉花体细胞胚胎发生的内外因素以及寻找棉花体细胞胚胎发生特异表达基因等几方面进行综述, 并对研究中存在的问题进行了讨论。     

棉花体细胞胚胎发生的研究进展

经过30多年的发展,已经在多个不同的棉花品种中获得了体细胞胚,并再生成苗。但由于体细胞胚胎发生往往受多种因素影响,如何从愈伤组织高效率地转化为胚性愈伤组织依然是限制棉花组织培养与遗传转化的关键问题之一。本文概述了棉花体细胞胚胎发生的研究进展,分别从棉花体细胞胚胎发生的起源、影响棉花体细胞胚胎发生的内外因素以及寻找棉花体细胞胚胎发生特异表达基因等几方面进行综述,并对研究中存在的问题进行了讨论。     

白蜡树属植物体细胞胚胎发生进展

综述了近年来国内外对白蜡树属植物体细胞胚胎发生的研究概况,对影响体细胞胚胎发生的主要可控因素以及体细胞胚胎发生过程、机理、组织学方面作了介绍,并提出了白蜡树属体细胞胚胎发生研究的应用前景。     

松柏类植物体细胞胚胎发生的研究进展

松柏类植物的体细胞胚胎发生既是繁育的一种手段,又是研究胚胎发育过程中结构、生理和分子事件的一种重要的模式系统.整个体细胞胚胎发生过程主要包括3个步骤:胚性组织的诱导和增殖、体细胞胚的成熟以及体细胞胚的萌发和转换.过去为了提高胚胎发育过程所做的努力主要都集中在胚的成熟阶段,这是因为一直认为能否成功再生的关键在于胚发育成熟阶段的处理.然而,在过去几年里,结合生理生化以及分子生物学的研究发现,胚胎发生的早期阶段对于完成整个发育过程也是至关重要的,早期阶段培养条件的优化可以显著提高培养过程中体细胞胚的数量和质量.此外,萌发过程培养条件的调节对于提高成熟体细胞胚的萌发率和转换率也很重要.因此,这些新的研究成果对于改善松柏类植物体细胞胚胎发生中的胚的诱导率和转换率低的现象具有重要的意义.     

松柏类植物体细胞胚胎发生的研究进展

松柏类植物的体细胞胚胎发生既是繁育的一种手段,又是研究胚胎发育过程中结构、生理和分子事件的一种重要的模式系统。整个体细胞胚胎发生过程主要包括3个步骤：胚性组织的诱导和增殖、体细胞胚的成熟以及体细胞胚的萌发和转换。过去为了提高胚胎发育过程所做的努力主要都集中在胚的成熟阶段,这是因为一直认为能否成功再生的关键在于胚发育成熟阶段的处理。然而,在过去几年里,结合生理生化以及分子生物学的研究发现,胚胎发生的早期阶段对于完成整个发育过程也是至关重要的,早期阶段培养条件的优化可以显著提高培养过程中体细胞胚的数量和质量。此外,萌发过程培养条件的调节对于提高成熟体细胞胚的萌发率和转换率也很重要。因此,这些新的研究成果对于改善松柏类植物体细胞胚胎发生中的胚的诱导率和转换率低的现象具有重要的意义。     

松柏类植物体细胞胚胎发生的研究与应用

松柏类植物体细胞胚胎发生的研究与应用唐巍杨映根桂耀林郭仲琛伍美保（中国科学院植物研究所,北京１０００９３）ＳＴＵＤＹＡＮＤＡＰＰＬＩＣＡＴＩＯＮＯＮＳＯＭＡＴＩＣＥＭＢＲＹ┐ＯＧＥＮＥＳＩＳＩＮＣＯＮＩＦＥＲＳＴａｎｇＷｅｉＹａｎｇＹｉｎｇ－ｇｅｎＧ...     

影响香根草体细胞胚胎发生和植株再生因素初探

为了探索提高香根草(Vetiveriazizanioides)遗传种质改良效率的有效途径,初步研究了影响香根草体细胞胚胎发生和植株再生的若干因素。以MS培养基为基本培养基,附加不同配比的生长素和细胞分裂素,对香根草的腋芽及无菌不定芽进行离体培养。结果表明,2,4-D是诱导体细胞胚胎发生的关键因素,当培养基中只含2,4-D而不含或少含细胞分裂素(6-BA)时,外植体经由体细胞胚胎发生途径形成再生植株。愈伤组织诱导频率在有的品种之间差异显著,最高的达到96.7%(cv.Zomba),最低的不到30%(cv.Malaysia);而有的品种之间差异不显著(例如cv.Kandy和cv.Sunshine)。胚性愈伤组织的再生能力可以长期保持,从未经继代培养的到持续继代第23代的胚性愈伤组织,再生频率都在80%以上,而且再生植株的生长良好。在3-7℃的低温下进行分化培养时,仍然有40.5%-50.0%不同世代的胚性愈伤组织还保持着再生能力。     

植物体细胞胚胎发生及其相关应答基因的研究进展

体细胞胚胎发生途径不仅是植物大规模克隆繁殖的重要途径,也是研究从单细胞到整体植株发育全过程的理想试验体系。植物体细胞胚胎发生的研究已经取得了很大的进展,但是也依然存在许多问题。根据近年来的相关研究报道,简述植物体细胞胚胎发生及此过程中相关应答基因的研究概况,探讨植物体细胞胚胎发生的生理生化基础,并对今后应该加强研究的关键问题提出了自己的看法。     

Factors Influencing Somatic Embryogenesis Induction and Plant Regeneration with Particular Reference to Arabidopsis thaliana (L.) Heynh

The broad applications of somatic embryogenesis, both in basic and applied research, have stimulated studies on the determination of in vitro conditions for the induction of somatic embryos and their conversion into plants. As a result, efficient protocols on SE induction and plant regeneration have recently become available for many plant species, including Arabidopsis thaliana (L.) Heynh., a model plant in genetics and embryogenesis.Studies on factors controlling in vitro plant morphogenesis are highly desirable not only for the development of improved regeneration systems, but also for the analysis of molecular mechanisms underlying plant embryogenesis. This review focuses on the conditions influencing the induction of embryogenic potential in in vitro cultured plant cells. The roles of explant type, endo- and exogenous plant growth regulators and stress factors in the induction of somatic embryogenesis are especially emphasized. Possible mechanisms by which different factors induce or modify embryogenic competence in cultured plant cells are also discussed. Since the production of genetically solid and true-to-type plants is desired, especially for transformation and micropropagation practice, the problem of the genetic characteristics of regenerants, in terms of their chimerism and somaclonal variation, is discussed in some detail.Special consideration is given to A. thaliana– a major model plant species for classical genetics and genomics. Recent availability of efficient embryogenic cultures in this organism makes it possible to benefit from advanced genomic research of Arabidopsis to study plant embryogenesis on the molecular level.     

Species-specific duplications driving the recent expansion of NBS-LRR genes in five Rosaceae species

Background

Disease resistance (R) genes from different Rosaceae species have been identified by map-based cloning for resistance breeding. However, there are few reports describing the pattern of R-gene evolution in Rosaceae species because several Rosaceae genome sequences have only recently become available.

Results

Since most disease resistance genes encode NBS-LRR proteins, we performed a systematic genome-wide survey of NBS-LRR genes between five Rosaceae species, namely Fragaria vesca (strawberry), Malus × domestica (apple), Pyrus bretschneideri (pear), Prunus persica (peach) and Prunus mume (mei) which contained 144, 748, 469, 354 and 352 NBS-LRR genes, respectively. A high proportion of multi-genes and similar Ks peaks (Ks = 0.1- 0.2) of gene families in the four woody genomes were detected. A total of 385 species-specific duplicate clades were observed in the phylogenetic tree constructed using all 2067 NBS-LRR genes. High percentages of NBS-LRR genes derived from species-specific duplication were found among the five genomes (61.81% in strawberry, 66.04% in apple, 48.61% in pear, 37.01% in peach and 40.05% in mei). Furthermore, the Ks and Ka/Ks values of TIR-NBS-LRR genes (TNLs) were significantly greater than those of non-TIR-NBS-LRR genes (non-TNLs), and most of the NBS-LRRs had Ka/Ks ratios less than 1, suggesting that they were evolving under a subfunctionalization model driven by purifying selection.

Conclusions

Our results indicate that recent duplications played an important role in the evolution of NBS-LRR genes in the four woody perennial Rosaceae species. Based on the phylogenetic tree produced, it could be inferred that species-specific duplication has mainly contributed to the expansion of NBS-LRR genes in the five Rosaceae species. In addition, the Ks and Ka/Ks ratios suggest that the rapidly evolved TNLs have different evolutionary patterns to adapt to different pathogens compared with non-TNL resistant genes.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-015-1291-0) contains supplementary material, which is available to authorized users.     

Somatic embryogenesis and regeneration of plants in the bamboo Dendrocalamus strictus

Somatic embryogenesis leading to plant regeneration has been achieved in the bamboo, Dendrocalamus strictus, by culturing seeds (caryopses) on B₅ basal medium supplemented with 2,4-dichlorophenoxyacetic acid. Callus cultures obtained from the embryonal end of the seeds differentiated chlorophyllous embryoids. On transfer to a germination medium (B₅ liquid, sucrose, indolebutyric acid, and -naphthaleneacetic acid) 40% of the embryoids developed into plantlets. Further development of the plantlets occured on B₅ liquid medium (half strength) + sucrose (1%) + IBA (5 × 10^–7M) + NAA (10^–7M).Abbreviations 2,4-D 2,4-dichlorophenoxyacetic acid - IBA Indolebutyric acid - NAA -naphthaleneacetic acid     

徐州市学龄期儿童肥胖现况调查及影响因素分析

目的:对徐州学龄期儿童的肥胖现状进行调查,分析其肥胖原因,以期找到有效的预防方法。方法:随机选取2014年1月-2016年1月徐州市学龄期儿童1021例,采用自理调查量表收集儿童及其父母的基本情况,统计儿童肥胖发生率,采用Logistic多因素回归分析儿童肥胖的影响因素。结果:男童肥胖率为11.15%(58/520),女童肥胖率为5.79%(29/501),男童肥胖率明显高于女童(P0.05);Logistic多因素回归分析显示,儿童肥胖危险因素有家族肥胖史(OR=3.647)、食欲(OR=2.065)、垃圾食品(OR=3.032)、甜食(OR=2.937),保护因素为周末运动时间(OR=-0.865)、体育特长(OR=-0.641)。结论:徐州学龄期儿童肥胖情况较为严重,应当控制肥胖儿童卡路里的摄入,积极进行体育锻炼,从各方面进行防治。     

海岛棉悬浮培养体细胞胚胎发生

取海岛棉无菌苗下胚轴作外植体,接种在含有激素２,４－Ｄ０．１ｍｇ／Ｌ和ＫＴ０．５ｍｇ／Ｌ的改良ＭＳ培养基上。经近２个月的诱导培养,获得淡黄色或淡灰色、松软、湿润、颗粒状的愈伤组织。将此类愈伤组织接入液体培养基进行悬浮培养,３～４个月后产生体细胞胚,获得各个时期的体细胞胚胎。胚性细胞悬浮系经适当的继代培养可长期保持成胚性。     

反刍动物的食物选择及其影响因素

反食物选择是反刍动物营养生态学的重要研究内容之一。本文阐述了食物选择概念及几种计算方法, 概述性介绍了食物选择的主要影响因素。动物形态学特征、植物营养质量、植物物理和化学因素、动物自身生理特征、行为学特征是影响反刍动物食物选择的主要因素。这些因素间的相互关系及作用机理构成这一领域基本研究内容。