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1.
S. Paul A. Dam A. Bhattacharyya T. K. Bandyopadhyay 《Plant Cell, Tissue and Organ Culture》2011,105(2):271-283
A reproducible protocol for direct and indirect somatic embryogenesis was established in a small aromatic tree, Murraya koenigii. Embryogenic callus was obtained from 90% zygotic embryonic axis (ZE) and 70% cotyledon (COT) explants in Murashige and Skoog
(MS) basal medium supplemented with 8.88 μM 6-benzyladenine (BA) and 2.675 μM α-naphthaleneacetic acid (NAA). Globular somatic
embryos were induced and further matured from such embryogenic callus by subsequent culture on the same basal media containing
thidiazuron (TDZ) (2.27–9.08 μM). The highest frequency of somatic embryos (14.58 ± 0.42) was recovered from ZE-derived callus
after 6 weeks. The age and type of explant and concentration of TDZ played an important role in the development of somatic
embryos. Explants excised from 60-day-old seed differentiated from 96.67% of ZE explants and 86.67% from COT explants when
cultured on MS basal medium supplemented with 4.54 and 9.08 μM TDZ, respectively, after 4 weeks. The best result obtained
for the average frequency of somatic embryos (11.28 ± 0.32) was from ZE explants, which was significantly higher than COT
explants (7.34 ± 0.97). Most of the somatic embryos (above 95%), irrespective of their origin, germinated after 4 weeks in
1/2 MS basal media containing 2.32 μM kinetin (KN) and 1.07 μM NAA. Well-rooted plantlets were successfully acclimatized.
Histological analysis and scanning electron micrographs confirmed the initiation, development, and germination of somatic
embryos from both explants. 相似文献
2.
Rangan Parimalan Akshatha Venugopalan Parvatam Giridhar G. A. Ravishankar 《Plant Cell, Tissue and Organ Culture》2011,105(3):317-328
Establishment, maintenance, regeneration, and transformation of somatic embryos by both direct and indirect means (callus-mediated)
was achieved for Bixa orellana, a tropical plant whose seeds produce commercially edible ‘annatto pigment,’ which mainly constitutes an apocarotenoid called
bixin. Callus-mediated methodology was found to be efficient in producing a greater number of embryos in a short time. The
maximum of 28 somatic embryos were produced in 16–18 weeks when immature zygotic embryonic stalks were inoculated onto Murashige
and Skoog (MS) medium containing B5 vitamins supplemented with 0.44 μM benzyladenine (BA), 0.054 μM α-naphthaleneacetic acid
(NAA), 2.89 μM gibberellic acid (GA3), 0.02 μM triiodobenzoic acid (TIBA), and 0.011 μM triacontanol (TRIA). Callus initiation from hypocotyl explants was obtained
on MS medium supplemented with 1.07–2.14 μM NAA and 10.2 μM BA. In 3 months, somatic embryos were produced when callus was
inoculated onto MS medium supplemented with 4.44 μM BA, 40 μM AgNO3, and 0.011 μM TRIA. Somatic embryos were efficiently regenerated on MS basal solid and liquid media supplemented with 0.44–4.4 μM
BA, 0.54–2.69 μM NAA, 4.92 μM 2iP, 2.1 μM calcium d-pantothenate, 0.21 μM biotin, 227.7 μM cysteine HCl monohydrate, and 108.6 μM adenine sulfate. Agrobacterium tumefaciens GV 3101 harboring pCAMBIA 1305.2 binary vector-mediated stable transformation of somatic embryos exhibited a transformation
frequency of 2.56%. As somatic embryogenesis in any perennial system is useful in terms of both commercial and scientific
nature, this somatic embryo-based transformation protocol for the commercially important dye-yielding tropical plant B. orellana is useful for its improvement through genetic engineering. 相似文献
3.
Dong-Mei Kong John E. Preece Hai-Long Shen 《Plant Cell, Tissue and Organ Culture》2012,108(3):485-492
Somatic embryogenesis was obtained from immature cotyledon explants that were cultured on half-strength Murashige and Skoog
(MS) salts and vitamins with 5.4 μM naphthaleneacetic acid (NAA) and 0.2 μM thidiazuron (TDZ) plus a 4 × 4 factorial combination
of 0, 9.8, 24.6, or 49.2 μM indole-3-butyric acid (IBA) and 0, 8.9, 22.2, or 44.4 μM 6-benzyladenine (BA). The addition of
44.4 μM BA improved the percentage of cotyledon explants that produced somatic embryos to >20%, if 9.8 or 24.6 μM IBA was
also present. Somatic embryogenesis was >30% when seeds were harvested on 31 July or 15 August. The addition of 50 or 70 g l−1 sucrose enhanced embryogenesis. Histological examination showed that somatic embryos originated from epidermis cells of zygotic
embryos. A peak germination rate (69%) was attained when somatic embryos were desiccated for 10 min before they produced green
cotyledons and elongating shoot tips. Of the germinated embryos from this desiccation treatment, 65.6% also grew roots and
therefore converted into plants. Chilling somatic embryos at 4°C for 15 days resulted in the highest germination rate (69.4%),
which was significantly higher than those without chilling treatment (27.6%). However <10% of the chilled germinated embryos
formed roots and grew into plants. Plantlets from somatic embryos were transplanted into a 2 vermiculite: 1 sphagnum peat
medium, where they had a survival rate of 80.8%, and had no morphological abnormalities. 相似文献
4.
ShapeRotator: An R tool for standardized rigid rotations of articulated three‐dimensional structures with application for geometric morphometrics 下载免费PDF全文
The quantification of complex morphological patterns typically involves comprehensive shape and size analyses, usually obtained by gathering morphological data from all the structures that capture the phenotypic diversity of an organism or object. Articulated structures are a critical component of overall phenotypic diversity, but data gathered from these structures are difficult to incorporate into modern analyses because of the complexities associated with jointly quantifying 3D shape in multiple structures. While there are existing methods for analyzing shape variation in articulated structures in two‐dimensional (2D) space, these methods do not work in 3D, a rapidly growing area of capability and research. Here, we describe a simple geometric rigid rotation approach that removes the effect of random translation and rotation, enabling the morphological analysis of 3D articulated structures. Our method is based on Cartesian coordinates in 3D space, so it can be applied to any morphometric problem that also uses 3D coordinates (e.g., spherical harmonics). We demonstrate the method by applying it to a landmark‐based dataset for analyzing shape variation using geometric morphometrics. We have developed an R tool (ShapeRotator) so that the method can be easily implemented in the commonly used R package geomorph and MorphoJ software. This method will be a valuable tool for 3D morphological analyses in articulated structures by allowing an exhaustive examination of shape and size diversity. 相似文献
5.
Daniela Lopes Paim Pinto Ana Maria Rocha de Almeida Mailson Monteiro Rêgo Maurecilne Lemes da Silva Evelyn Jardim de Oliveira Wagner Campos Otoni 《Plant Cell, Tissue and Organ Culture》2011,107(3):521-530
Mature zygotic embryos of three genotypes of Passiflora edulis Sims, including ‘FB-100’, ‘FB-200’, and ‘FB-300’ were incubated on a Murashige and Skoog (MS) (1962) medium supplemented with different concentrations (18.1–114.8 μM) of 2,4-diclorophenoxyacetic acid (2,4-D) and 4.4 μM of
6-benzyladenine (BA). MS basal medium and MS with BA induced germination of P. edulis embryos. The highest frequencies of embryogenic calli were observed when explants were incubated on MS medium supplemented
with 72.4 μM 2,4-D and 4.4 μM BA for ‘FB-200’, which showed the highest potential for embryogenic callus formation. Cytological
and histological analyses of pro-embryogenic callus revealed two distinct cell types: thin-walled, small, isodiametric cells
with large nuclei and dense cytoplasm, typical of intense metabolic activity; and elongated and vacuolated cells, with small
nuclei and less dense cytoplasm. Differentiation of somatic embryos was promoted on MS medium supplemented with activated
charcoal and indole-3-acetyl-l-aspartic acid (IAA-Asp) either with or without 2,4-D. However, no conversion of somatic embryos into plantlets was observed. 相似文献
6.
T. H. Lan P. I. Hong C. C. Huang W. C. Chang C. S. Lin 《In vitro cellular & developmental biology. Plant》2009,45(1):44-47
Whole plants were regenerated from excised leaves of Drimiopsis kirkii Baker (Lily of the Valley) through direct somatic embryogenesis. An initial exposure to a low level of 2,4-dichlorophenoxyacetic
acid (2,4-D, 0.45 μM) in the medium was essential in inducing the direct formation of somatic embryos. A high concentration
of 2,4-D (4.52 μM) in the proliferation medium reduced embryogenesis and enhanced callus formation. The presence of kinetin
in the medium enhanced the somatic-embryogenesis-inducing effect of 2,4-D (0.45 μM). The maximum embryogenesis rate (4,026
somatic embryos per gram of leaf) was obtained in explants cultured for 30 d in medium supplemented with 2.33 μM kinetin and
0.45 μM 2,4-D (embryo induction medium). Kinetin (4.65 μM) also enhanced embryo germination (97.6%), but the presence of α-naphthalene
acetic acid in the medium drastically reduced embryo germination. Following conversion, the regenerated plantlets were transferred
to soil and showed normal morphological characteristics. 相似文献
7.
Q. C. Liu H. Zhai Y. Wang D. P. Zhang 《In vitro cellular & developmental biology. Plant》2001,37(5):564-567
Summary Using 15 Chinese and Japanese cultivars of sweetpotato, Ipomoea batatas (L.) Lam., we succeeded in developing an efficient plant regeneration system from embryogenic suspension cultures. The embryogenic
callus derived from shoot apices of the 15 cultivars was used to initiate embryogenic suspension cultures in Murashige and
Skoog (MS) medium containing 9.05 μM 2,4-dichlorophenoxyacetic acid (2,4-D). Rapidly proliferating and well-dispersed embryogenic suspension cultures were established.
Cell aggregates 0.7–1.1 mm in size from embryogenic suspension cultures were transferred to solid MS medium supplemented with
9.05 μM of 2,4-D and formed embryogenic callus with somatic embryos. The embryogenic callus with somatic embryos was further transferred
to MS medium supplemented with 3.78 μM of abscisic acid, resulting in the germination of somatic embryos. Within 20 wk after the initiation, the frequencies of
cell aggregates forming plantlets reached approximately 100% for the 15 tested cultivars. These plantlets, when transferred
to soil, showed 100% survival. No morphological variations were observed. 相似文献
8.
P. I. P. Perera D. M. D. Yakandawala V. Hocher J-L. Verdeil L. K. Weerakoon 《Plant Cell, Tissue and Organ Culture》2009,96(2):171-180
The effect of growth regulators on induction of androgenesis in coconut was investigated using seven different growth regulators
at various concentrations and combinations. Three auxins (1-naphthalene acetic acid—NAA, indoleacetic acid—IAA, picloram)
and three cytokinins (2-isopentyl adenine-2-iP, kinetin, zeatin) were tested either alone or in combination with 2,4-dichlorophenoxyacetic
acid (2,4-D), using modified Eeuwens Y3 liquid medium as the basal medium. Among the tested auxins, 100 μM NAA in combination
with 100 μM 2,4-D enhanced the production of calli/embryos (123) whereas IAA and picloram showed negative and detrimental
effects, respectively, for androgenesis induction over 100 μM 2,4-D alone. Kinetin and 2-iP enhanced the production of calli/embryos
when 100 μM 2,4-D was present in the culture medium. Both cytokinins at 10 μM yielded the highest frequencies of embryos (113
and 93, respectively) whereas zeatin (1 or 2.5 μM) had no impact on microspore embryogenesis. When calli/embryos (produced
from different treatments in different experiments) were sub-cultured in somatic embryo induction medium (Y3 medium containing 66 μM 2,4-D), followed by maturation medium (Y3 medium without growth regulators) and germination medium (Y3 medium containing 5 μM-6-benzyladenine—BA and 0.35 μM gibberellic acid—GA3), plantlets were regenerated at low frequencies (in most treatments ranging from 0% to 7%). 相似文献
9.
G. G Ning S. P Bai M. Z Bao L. Liu 《In vitro cellular & developmental biology. Plant》2007,43(2):95-100
Using immature embryos and cotyledons as explants, a successful system to culture immature embryos and induce direct regeneration
from cotyledons was established for Prunus mume “Xuemei”. For immature embryo culture, a high frequency of plantlet formation (89.5%) from the embryonic axis was obtained
using half-strength Murashige and Skoog (1/2 MS) medium supplemented with 13.2 μM 6-benzyladenine (BA) and 2.7 μM 1-naphthaleneacetic
(NAA). Shoots formed directly from cotyledons with the embryo axis intact when explants were cultured on 1/2 MS medium containing
2.2 μM BA with different combinations of NAA (2.7, 5.4 μM) and indole-3-butyric acid (IBA) (0, 2.5, 5.0 μM). Better results
were achieved when the embryonic axis was removed from the cotyledons and cultured on 1/2 MS medium supplement with 13.2 μM
BA, 2.7 μM NAA or 2.2 μM BA, 2.2 μM thidiazuron (TDZ), and 2.7 μM NAA, respectively. Regenerated shoots were successfully
rooted on 1/2 MS or Woody Plant medium (WPM) supplemented with 2.5–5.0 μM IBA. The effect of the embryonic axis, BA, and TDZ
on cotyledon regeneration was investigated in detail. Rooted plantlets were transferred to soil successfully. 相似文献
10.
Hui Song Qun-Feng Lou Xiang-Dong Luo Joseph N. Wolukau Wei-Ping Diao Chun-Tao Qian Jin-Feng Chen 《Plant Cell, Tissue and Organ Culture》2007,90(3):245-254
Six experiments (including pretreatment, embryonic callus induction media, preculture conditions, embryo induction media,
embryo germination media, and genotypic effects) were conducted to develop an efficient cucumber (Cucumis sativus L., 2n = 2x = 14) anther culture protocol. Pretreatment and embryo induction were key factors for successful anther culture. Suitable
temperature stress depended on the ecotype, i.e., cucumbers from cold areas responded well to cold shock whereas those from
temperate areas responded well to heat treatment. The best medium for embryonic callus induction was MS medium supplemented
with 4.44 μM BA, 2.26 μM 2, 4-D, 4.64 μM KIN, 3% sucrose and 0.8% agar. For embryo induction, MS medium supplemented with
0.54 μM NAA, 13.32 μM BA, 3% sucrose and 0.8% agar was optimal, and for embryo germination MS medium containing 2.22 μM BA,
6% sucrose and 1.2% agar was best. Using this protocol, we produced callus from 16 genotypes and regenerated plants from three
of 20 evaluated. Three embryos per anther and 42 DH per 45 anthers (93% success) were obtained for cv. Ningjia No. 1, which
was an improved result over a previous report. The origin of regenerants from microspores was determined by cytological, morphological
and AFLP analyses. 相似文献
11.
Cheng-Hao Li Bao-Guang Liu Tae-Dong Kim Heung-Kyu Moon Yong-Eui Choi 《Plant biotechnology reports》2008,2(4):259-265
Picea koraiensis, called Korean spruce, is an evergreen tree and found mostly in northeast Asia. In this study, plant regeneration via somatic
embryogenesis from open-pollinated immature zygotic embryos of nine genotypes of elite trees was established. Immature zygotic
embryos were cultured onto RJW medium modified from 505 medium with 21.48 μM NAA, 2.22 μM BA, and 2.32 μM KT. The average
frequency for all nine genotypes was 74.2%. Embryogenic calluses of the nine genotypes of elite trees were subcultured on
RJW basal medium containing 8.06 μM NAA, 1.11 μM BA, and 1.16 μM kinetin. The calluses of three lines, 3#, 9#, and 2#, were actively proliferated but others were not. Somatic embryogenesis was induced from the embryogenic callus in genotypes
of 3#, 9#, and 2# on RJW medium with ABA and 60 g l−1 sucrose. Cotyledonary somatic embryos were subjected to a drying process. The drying of embryos by uncapping the culture
bottle for 5 days on a clean bench resulted in a high frequency of germination of somatic embryos (87% in RJW medium). However,
plantlet conversion from germinated embryos was greatly reduced and the optimal medium for plant conversion was 1/2 WPM or
1/2 BMI medium. In conclusion, we have, for the first time, established a plant regeneration system via somatic embryogenesis
in the Korean spruce, which can be applied for rapid micropropagation of elite trees. 相似文献
12.
When cotyledonary explants, excised from in vitro germinated seedlings, of pomegranate (Punica granatum L.) were incubated on solid Murashige and Skoog (1962) medium supplemented with 21 μM naptheleneacetic acid (NAA) and 9 μM 6-benzyladenine (BA), 80% of explants developed callus.
A high frequency of shoot organogensis was obtained when explants were incubated on MS medium supplemented with 8 μM BA, 6 μM
NAA, and 6 μM giberrellic acid (GA3). However, adding 24 μM silver nitrate (AgNO3) to this medium markedly enhanced shoot regeneration frequency (63%) and mean number of shoots per explant (11.26) and length
of shoots (2.22 cm). Highest frequency of in vitro rooting, mean number of roots/shoot (4.32), and mean root length (2.71 cm)
were obtained when regenerated shoots were transferred to half-strength MS medium supplemented with 0.02% activated charcoal.
Well-rooted plantlets were acclimatized, and then transferred to soil medium. Moreover, when zygotic embryos of P. granatum, excised from seeds collected at 16 weeks following full bloom, were incubated on MS medium containing 30 g l−1 sucrose, 15% coconut water, 21 μM NAA, and 9 μM BA, they developed the highest frequency of embryogenic callus, clumps with
globular embryos, and mean number of both globular and heart-shaped embryos per callus clump. Subjecting zygotic embryo explants
to six-week dark incubation period was essential for embryogenic callus induction, and these were subsequently transferred
to 16 h photoperiod for further growth and development of somatic embryos. Germination of somatic embryos was observed when
these were transferred to MS medium was supplemented with 60 g l−1 sucrose. 相似文献
13.
Jana Máchová Miroslav Prokeš Milan Peňáz Vlastimil Baruš Hana Kroupová 《Reviews in Fish Biology and Fisheries》2010,20(3):409-415
The effects of Diazinon 60 EC (organophosphate insecticide, active substance diazinon) on mortality, growth rate, early ontogenetic
rate, and occurrence of malformations was studied in embryos and larvae of tench, Tinca tinca (L.). The exposure of fish to 0, 10, 100, 1,000, and 3,000 μg dm−3 of Diazinon 60 EC was initiated 24 h after fertilization of eggs and concluded 32 days later. At the highest concentration
tested (3,000 μg dm−3), total mortality was observed within the first 15 days of exposure. A concentration of 1,000 μg dm−3 caused high incidence of malformations, decrease in growth rate and ontogenetic development slowed down. A concentration
of 100 μg dm−3 mildly decreased growth rate, but at 10 μg dm−3 no changes compared to the control were observed. Thus, Diazion 60 EC at the concentration of 10 μg dm−3 is not dangerous for the embryos and larvae of tench. 相似文献
14.
Elisa Ferreira Moura Marília Contin Ventrella Sérgio Yoshimitsu Motoike Adauto Quirino de Sá Júnior Mychelle Carvalho Candida Elisa Manfio 《Plant Cell, Tissue and Organ Culture》2008,95(2):175-184
The aim of this paper was to describe the histological events that led to somatic embryogenesis in macaw palm (Acrocomia aculeata (Jacq.) Lodd. ex Martius). Zygotic embryos were inoculated on Y3 medium containing 9 μM 4-amino-3,5,6-trichloropicolonic acid (picloram). Somatic embryos regenerated from nodular callus
on induction medium with activated charcoal under photoperiod or without activated charcoal under dark. Many proembryos originated
from the fundamental meristem after 10–20 days of culture. When transferred to medium containing activated charcoal, under
photoperiod, calli regenerated into somatic embryos of unicellular origin. These embryos had protoderm, plumule and procambial
strands and some of them could germinate. After 30–40 days of culture, meristematic masses grew from procambial cells. The
masses generated nodular callus, and after transfer to medium without activated charcoal, under dark, they generated somatic
embryos of multicellular origin. Those embryos did not regenerate into plants. 相似文献
15.
Ya Su Liya Wei Hao Tan Jing Li Wenping Li Lei Fu Tongxin Wang Le Kang X. Steve Yao 《Journal of biophotonics》2020,13(2)
Noninvasive visualization of embryos at different development stages is crucial for the understanding of the basic developmental biology. It is therefore desirable to have an imaging tool capable of rapidly evaluating the effects of gene manipulation or genome editing in developing embryos for the studies of gene functions and genetic engineering. Here, we propose and demonstrate a novel use of optical coherence tomography (OCT) to noninvasively exam the embryonic development of the migratory locusts in real time with 3‐dimensional (3D) view capability. In particular, we obtain the sufficiently high spatial resolution tomographic 2D and 3D images of live locust embryos throughout their development processes. We show that not only we are able to noninvasively observe all previously known forms of blastokinesis as an embryo develops, such as anatrepsis, katatrepsis, revolution, rotation and diapauses, and determine their precise occurring time or duration, but also discover an unreported rotation form we named “twist.” In addition, with the OCT images we determined the exact occurring time of diapauses of the locusts from Tibetan plateau for the first time. Finally, we demonstrate that OCT systems can be used to rapidly capture the development defects of genetically modified embryos in which certain genes essential for embryonic development were suppressed by RNA interference. Our work shows that OCT is an enabling imaging tool with sufficient spatial resolution for the rapid evaluation of embryonic variations of small animals. 相似文献
16.
Carlos I Lorda-Diez Juan A Montero Juan A Garcia-Porrero Juan M Hurle 《BMC developmental biology》2010,10(1):69
Background
Transforming growth factor β proteins (Tgfβs) are secreted cytokines with well-defined functions in the differentiation of the musculoskeletal system of the developing limb. Here we have studied in chicken embryos, whether these cytokines are implicated in the development of the embryonic limb bud at stages preceding tissue differentiation. 相似文献17.
Chow-Chin Tong Yew-Keong Choong Nor-Aini-B Umar Mohamed-Mustapha Noordin Suhaila Mohamed 《World journal of microbiology & biotechnology》2009,25(4):687-695
Ganoderma lucidum powder using hot water and methanol extraction methods indicated a twofold more active cytotoxic activity with IC50 of 44 ± 3.8 μg/ml in the latter method. The representative dose-response curves of the G. lucidum crude extracts on J558 cell-lines revealed that there were great similarities between the curves which reflected rapid killing
activities. The percentage viability of the J558 cell exposed to these crude extracts was dose dependent only up to 150 μg/ml.
After which, there was no significant reduction when the dose was increased to 200 or 400 μg/ml. The morphological alterations
induced by the crude extract were examined under the phase contrast, fluorescent and electron microscopy. When J558 cells
were treated with doses higher than 50 μg/ml of the crude extract, obvious morphological changes and apoptosis occurred after
72 h. At 400 μg/ml, most of the cells showed necrosis characterized as small fragments with uniformly stained red nuclei.
The apoptotic and necrotic cells increased by 16.5 and 29.1%, respectively whereas the viable cells decreased by as much as
45.6. The mode of cell death via apoptosis was 3.6% higher than necrosis. However, these morphological changes were not observed
in the case of 3T3 cells. Results obtained from scanning electron microscopy and transmission electron microscopy further
confirmed the occurrence of various apoptotic and necrotic features. 相似文献
18.
Assessing the effects of low boron diets on embryonic and fetal development in rodents using in vitro and in vivo model systems 总被引:2,自引:0,他引:2
Lanoue L Taubeneck MW Muniz J Hanna LA Strong PL Murray FJ Nielsen FH Hunt CD Keen CL 《Biological trace element research》1998,66(1-3):271-298
To date, boron (B) essentiality has not been conclusively shown in mammals. This article summarizes the results of a series
of in vitro and in vivo experiments designed to investigate the role of B in mammalian reproduction. In the first study, rat
dams were fed either a low (0.04 μg B/g) or an adequate (2.00 μg B/g) B diet for 6 wk before breeding and through pregnancy;
reproductive outcome was monitored on gestation day 20. Although low dietary B significantly lowered maternal blood, liver,
and bone B concentrations, it had no marked effects on fetal growth or development. The goal of the second study was to assess
the effects of B on the in vitro development of rat postimplantation embryos. Day 10 embryos collected from dams fed either
the low or adequate B diets for at least 12 wk were cultured in serum collected from male rats exposed to one of the two dietary
B treatments. Dams fed the low B diet had a significantly reduced number of implantation sites compared to dams fed the B-adequate
diet. However, embryonic growth in vitro was not affected by B treatment. The aim of study 3 was to define the limits of boric
acid (BA) toxicity on mouse preimplantation development in vitro. Two-cell mouse embryos were cultured in media containing
graded levels of BA (from 6 to 10,000 μM). Impaired embryonic differentiation and proliferation were observed only when embryos
were exposed to high levels of BA (>2000 μM), reflecting a very low level of toxicity of BA on early mouse embryonic development.
Study 4 tested the effects of low (0.04 μg B/g) and adequate (2.00 μg B/g) dietary B on the in vitro development of mouse
preimplantation embryos. Two-cell embryos obtained from the dams were cultured in vitro for 72 h. Maternal exposure to the
low B diet for 10, 12, and 16 wk was associated with a reduction in blastocyst formation, a reduction in blastocyst cell number,
and an increased number of degenerates. Collectively, these studies support the concept that B deficiency impairs early embryonic
development in rodents. 相似文献
19.
20.
Efficient somatic embryogenesis (SE) and in vitro flowering and fruiting were achieved in Saposhnikovia divaricata (Turcz.) Schischk. Friable embryogenic callus developed from the root, internode, and leaf explants on Murashige and Skoog
medium (MS) with 2.26 μM 2,4-dichlorophenoxyacetic acid (2,4-D), and subsequently developed into somatic embryos on MS medium
containing 4–5% sucrose, 1.74 μM naphthaleneacetic acid (NAA), 4.44 μM 6-benzylaminopurine (BA), and 1.90 μM abscisic acid
(ABA). Then the mature embryos were separated and transferred onto MS with 3% sucrose and 0.6% agar for further development
and conversion to plantlets. In vitro flowering and fruiting were obtained when the subcultures were carried out for over
15 months. Paclobutrazol (PP333) or ethephon (ETH) at low levels promoted flowering significantly. Also, abnormal rootless
somatic embryos of S. divaricata could form flowers and fruits in vitro. 相似文献