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Formation of somatic embryos was dependent on concentrationof specific auxin and mineral nutrient formulation. On N6 mediumwith low levels of 2,4-D somatic embryos were obtained fromunemerged inflorescences and immature embryos. Direct differentiationof somatic embryos, a rare feature of regeneration in graminaceousplants, was more apparent from immature embryos than from inflorescences.On the other hand, on MS medium with different levels of 2,4-Dcompact callus-like masses appeared which regenerated to formplantlets on auxin-free medium. At higher levels of 2,4-D andalso on N6 medium compact tissues (morphogenic calli) appearedwhich were made up of thallus-like structures. Echinochloa, immature embryo, unemerged inflorescence, somatic embryo 相似文献
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The present paper reports the embryogenic callus formation and plantlet regeneration of Phragmites communis. The results have been obtained as follows: The efficiency of callus induction was much higher, if reed seeds were used as explants. No dedifferentiation was observed by using leaf sheath and leaf blade as explants. The optim, um concentration of sucrose was 4% in medium. VB group and inositol had beneficial effects on callus growth. But yeast extract inhibited callus induction and callus growth markedly. For this inhibited reaction, the higher concentration, the more obviously the callus growth was inhibited. Higher levels of 2,4-D had unfavourable effects on callus growth in callus subculture. The concentration of 2,4-D in dedifferentiation medium had relation to embryogenic callus formation. Embryogenic callus had higher frequency of differentiation for long-term subculture. On the other hand, nonembryogenic callus most often lost their morphogenetic competence. Authors found that the surface structure of the two types of calluses was different by means of observation by scanning electron microscope. The peroxidase and the esterase isoenzyme pat- terns, as well as the soluble protein of both types of calluses were different too. 相似文献
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Angelo Schuabb Heringer Tatiana Barroso Amanda Ferreira Macedo Claudete Santa-Catarina Gustavo Henrique Martins Ferreira Souza Eny Iochevet Segal Floh Gon?alo Apolinário de Souza-Filho Vanildo Silveira 《PloS one》2015,10(6)
The development of somatic cells in to embryogenic cells occurs in several stages and ends in somatic embryo formation, though most of these biochemical and molecular changes have yet to be elucidated. Somatic embryogenesis coupled with genetic transformation could be a biotechnological tool to improve potential crop yields potential in sugarcane cultivars. The objective of this study was to observe somatic embryo development and to identify differentially expressed proteins in embryogenic (E) and non-embryogenic (NE) callus during maturation treatment. E and NE callus were cultured on maturation culture medium supplemented with different concentrations (0.0, 0.75, 1.5 and 2.0 g L-1) of activated charcoal (AC). Somatic embryo formation and differential protein expression were evaluated at days 0 and 21 using shotgun proteomic analyses. Treatment with 1.5 g L-1 AC resulted in higher somatic embryo maturation rates (158 somatic embryos in 14 days) in E callus but has no effect in NE callus. A total of 752 co-expressed proteins were identified through the SUCEST (The Sugarcane EST Project), including many housekeeping proteins. E callus showed 65 exclusive proteins on day 0, including dehydrogenase, desiccation-related protein, callose synthase 1 and nitric oxide synthase. After 21 days on maturation treatment, 14 exclusive proteins were identified in E callus, including catalase and secreted protein. NE callus showed 23 exclusive proteins on day 0 and 10 exclusive proteins after 21 days on maturation treatment, including many proteins related to protein degradation. The induction of maturation leads to somatic embryo development, which likely depends on the expression of specific proteins throughout the process, as seen in E callus under maturation treatment. On the other hand, some exclusive proteins can also specifically prevent of somatic embryos development, as seen in the NE callus. 相似文献
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Somatic Embryogenesis and Plantlet Regeneration from Callus of Mature Zygotic Embryos of Masson Pine
Embryogenic cultures were initiated from mature zygotic embryos of masson pine (Pinus massoniana Lamb. ) on DCR medium supplemented with 2, 4-D 10 mg/L, KT and BA each at 4 mg/L. Pale and translucent calli with early stage proembryos were maintained and multiplicated on DCR medium supplemented with 2, 4-D 1.0 mg/L KT and BA each at 0.4 mg/L. Robust late-stage proembryos were obtained when the calli were cultured on DCR medium containing 9000 mg/L myo-inositol. Abscisic acid and activated charcoal promoted the formation of cotyledonary embryos at the highest frequency of 35.1 %. Mature somatic embryos could germinate and develop further into plantlets when they were isolated and cultured on a hormone-free DCR medium. 相似文献
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Saadet Büyükalaca Ferda Mavituna Layla Z. A. Rahman 《Journal of plant biochemistry and biotechnology.》2003,12(2):143-146
This study reports a novel method for embryo separation by cold treatment of heterogeneous suspension cultures which contain embryogenic single cells, cell clusters and embryos at various stages of development. The method was applied to embryo suspension cultures of pepper (Capsicum annuum) and sugarcane (Saccharum officinarum). In both plants, single cells lost their viability dramatically over a few days while the viability of embryos remained above 95% for 25-30 days when kept at 5 °C. The effect of duration of cold treatment on embryo germination was also tested. The optimal duration of cold treatment was found to be 10 days for sugarcane and 21 days for pepper. After the cold treatment, the germination percentages were 90% and 96% for sugarcane and pepper, respectively. 相似文献
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DNA Methylation and Embryogenic Competence in Leaves and Callus of Napiergrass (Pennisetum purpureum Schum.) 总被引:1,自引:1,他引:0 下载免费PDF全文
Quantitative and qualitative levels of DNA methylation were evaluated in leaves and callus of Pennisetum purpureum Schum. The level of methylation did not change during leaf differentiation or aging and similar levels of methylation were found in embryogenic and nonembryogenic callus. 相似文献
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Frequency of safflower (Carthamus tinctorius L.) somatic embryogenesis, number of somatic embryos per responding explant and somatic embryo maturation and germination were affected by genotype, explant age, carbon source, and ethylene. Among 8 cultivars tested, 7 were embryogenic with varying frequencies. The best response was obtained with cv. Girna. Whole cotyledonary explant from 10-d-old plants was best responding compared to 5- or 15-d-old ones. Among different carbon sources, sucrose at 87.6 mM concentration was most suitable for embryo induction, maturation and germination. Of the different ethylene inhibitors, silver nitrate at 50 [micro ]M concentration significantly increased the embryogenic frequency and also the number of embryos per responding explant. Silver nitrate has pronounced effect on embryo maturation but had no effect on germination. 相似文献
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Puigderrajols P Celestino C Suils M Toribio M Molinas M 《International journal of plant sciences》2000,161(3):353-362
In cork oak (Quercus suber L.), recurrent embryogenesis is produced in vitro through autoembryony without exogenous plant growth regulators (PGRs); secondary embryos appear on the embryo axis but seldom on cotyledons. Focusing mainly on the histological origin of neoformations, we investigated the influence of the embryo axis and exogenous PGRs on the embryogenic potential of somatic embryo cotyledons. Isolated cotyledons of somatic embryos became necrotic when cultured on PGR-free medium but gave secondary embryos when cultured on media containing benzyladenine and naphthaleneacetic acid. Cotyledons of cork oak somatic embryos are competent to give embryogenic responses. Isolated cotyledons without a petiole showed a lower percentage of embryogenic response than did those with a petiole. In petioles, somatic embryos arose from inner parenchyma tissues following a multicellular budding pattern. Joined to the embryo axis, cotyledons did not show morphogenic responses when cultured on PGR-free medium but revealed budlike and phylloid formations when cultured on medium with PGRs. The different morphogenic behavior displayed by somatic cotyledons indicates an influence of the embryo axis and indicates a relationship between organogenic and embryogenic regeneration pathways. 相似文献
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以杂交狼尾草初级愈伤为材料,运用方差分析的方法研究不同因素对杂交狼尾草胚性愈伤诱导率与植株再生率的影响。结果发现,2,4-D和TDZ对杂交狼尾草胚性愈伤诱导影响显著,最佳的胚性愈伤诱导培养基为MS+3.0 mg·L-12,4-D+0.4 mg·L-16-BA+0.2 mg·L-1 TDZ,诱导率为54%;愈伤分化培养基以附加0.1 mg·L-1 TDZ+0.2 mg·L-16-BA+3.2 mg·L-1 CuSO4的 MS培养基为最佳,再生率为68.33%,褐化率为8.33%;分化培养基中添加0.8~3.2mg·L-1的CuSO4均能促进杂交狼尾草愈伤组织分化,而添加AgNO3对杂交狼尾草愈伤分化无显著影响。该技术为离体诱变获得杂交狼尾草低温种质材料奠定了基础。 相似文献
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Shen-Jie Wu Hai-Hai Wang Fei-Fei Li Tian-Zi Chen Jie Zhang Yan-Jie Jiang Yezhang Ding Wang-Zhen Guo Tian-Zhen Zhang 《Plant Molecular Biology Reporter》2008,26(3):174-185
Agrobacterium-tumefaciens-mediated transformation of cotton embryogenic calli (EC) was enhanced by choosing appropriate EC and improving efficiency
of coculture, selection cultivation, and plant regeneration. After 48-h cocultivation, the number of β-glucuronidase (GUS)-positive
calli characterized by yellow, loose, and fine-grained EC was twofold greater than that of gray, brown, and coarse-granule
EC. It indicated that efficiency of transient transformation was affected by EC morphology. And transient transformation efficiency
was also improved by cocultivation on the medium adding 50 mg l−1 acetosyringone at 19°C for 48 h. Subculturing EC on the selection medium with low cell density was beneficial to production
of more kanamycin-resistant (Km-R) calli lines. From an original 0.3-g EC, an average of 20 Km-R calli lines were obtained
from a selection dish and the GUS-positive rate of Km-R clones was 81.97%. A large number of normal plants were rapidly regenerated
on the differentiation medium with dehydration treatments and the GUS-positive rate of regeneration plants was about 72.60%.
Polymerase chain reaction analysis of GUS-positive plantlets revealed a 100% positive detection rate for neomycin phosphotransferase
II gene and uidA. Southern blot of transgenic plants regenerated from different Km-R calli lines demonstrated that the target gene, mostly
with the low copy number, has been integrated into the cotton genome.
Shen-Jie Wu and Hai-Hai Wang should be considered as joint first authors 相似文献
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基因枪法转化籼稻胚性愈伤组织获得可育的转基因植株 总被引:22,自引:0,他引:22
以籼稻胚性愈伤组织作为基因枪法转化的靶材料,建立了可重复的、高效的籼稻转化系统。从籼稻成熟胚诱导生长3 ̄4周的愈伤组织,经过2 ̄6周继代培养后,可以形成足够量的颗粒状胚性愈伤组织。用含有bar基因和B.t.δ-内毒素基因的质粒pFWZ16轰击转化胚性愈伤组织,在含2 ̄4mg/L Basta的培养基上进行筛选、预再生、再生及长根培养,并通过干燥处理增加再生频率和出苗数。从接种到获得转化小植株只需要4 相似文献
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以龙眼‘红核子’LC2悬浮细胞系诱导的胚性愈伤组织为基本材料,按照龙眼体细胞胚胎同步化方法诱导获得龙眼体胚不同阶段材料,并以龙眼体细胞胚胎发生不同阶段混合材料作为试验材料,采用RT-PCR结合RACE技术分离并克隆龙眼中编码同源异型结构域蛋白的转录因子WUSCHEL(简称DlWUS)的cDNA全长及DNA序列,并进行序列分析与表达分析。结果表明:DlWUS的cDNA全长1 110bp,开放阅读框(ORF)858bp,共编码285个氨基酸(GenBank登录号为KM017506),DlWUS的DNA包含2个内含子。序列分析表明,DlWUS是一个不稳定的亲水蛋白,不含信号肽,亚细胞定位于细胞核,具跨膜结构和Homeodomain超级家族的保守结构域以及WUS转录因子家族特有的WUS box和EAR-like结构域,推测该目的基因确实为WUS转录因子。系统进化分析显示,龙眼DlWUS与脐橙WUS归为一个分支,亲缘关系较近。实时荧光定量PCR分析结果表明,在龙眼体细胞胚胎发生整个过程中,DlWUS均有表达,但仅在球形胚时期表达量较高,说明DlWUS可能主要在球形胚阶段发挥作用,并且在一定浓度范围内,外源施加IAA和GA3能够促进DlWUS基因的表达,而外源施加SA则抑制DlWUS基因的表达。 相似文献
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Callus cultures were induced starting from excised mature embryosin spring barley, Hordeum vulgare cv Maxima On a medium containinga high level of auxin, a first primary callus was induced whichwas friable, unorganized and capable of direct plant regenerationin the tested conditions This callus type was characterizedby fast growth and high variability in chromosome number Subsequently,a secondary callus type arose from the primary calli subculturedon the same medium in the light This callus type was white andcompact and consisted predominantly of diploid cells When transferredto hormone-free medium it gave rise to green shoots Completerooting of the shoots was achieved on half-strength basal mediumfollowed by exposure to higher light intensity Regenerated plantletscould then be transferred directly into soil without sufferingany loss in vitality Although showing different degrees in morphologicalvariability, they all maintained the diploid chromosome number Hordeum vulgare L, spring barley, morphogenic calli, organogenesis 相似文献
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Somatic Embryogenesis: Factors Influencing Coordinated Behaviour of Cells as an Embryogenic Group 总被引:11,自引:1,他引:10
A number of common features are associated with a great diversityof observations of somatic embryogenesis in vitro. There arefundamental homologies between direct and indirect somatic embryogenesis,and between single-cell and multiple-cell initiation. Many ofthe observed differences can be attributed to whether or notcells require redetermination to the embryogenic state, andto differences in the nearest neighbour relationships of initiatingcells. The observed pattern of morphogenesis depends on whethera group of cells can establish and maintain coordinated behaviouras an embryogenic unit and will be influenced by factors whichaffect intercellular communication. Somatic embryogenesis, tissue culture, cell-cell interactions 相似文献