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1.
Somatic embryogenesis in wild cherry (Prunus avium) 总被引:3,自引:0,他引:3
Garin Elisabeth Grenier Emmanuel Grenier-De March Ghislaine 《Plant Cell, Tissue and Organ Culture》1997,48(2):83-91
Indirect somatic embryogenesis was obtained inPrunus avium L. from either somatic or zygotic embryos. An embryogenic line
was established by reinduction of embryogenic calluses from somatic embryos. The line was maintained for more than 3 years
through 6 generations of embryogenic cultures. In the last 2 generations, more than 50% of the explants were embryogenic.
Embryos at different stages of development were produced. Among cotyledonary-stage embryos, 50% had two cotyledons and a distinct
hypocotyl, 43% had one or more than 2 cotyledons and 7% had fused cotyledons. Most of the embryos were translucent and conversion
into plantlets was very rare. Secondary embryos could be observed to occur with low frequency from cultured somatic embryos
and from embryos emerging from calluses. Indirect somatic embryogenesis was also induced from immature zygotic embryos. From
one donor tree, 51% of the explants were embryogenic when cultured on a medium containing 0.9 μM kinetin, 0.9 μM BA and 0.5
μM NAA.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
2.
Glória Pinto Sónia Silva Lucinda Neves Clara Araújo Conceição Santos 《Trees - Structure and Function》2010,24(4):763-769
We recently described a protocol for Eucalyptus globulus somatic embryogenesis (SE). For its immediate use at industrial levels, some stages of the process require better control.
In particular, SE germination rates are variable, decreasing SE efficacy. As reserves may play a central role in embryogenic
processes, we followed histocytological changes and reserve fluctuations, during SE. For SE induction, explants of mature
zygotic embryos were grown on Murashige and Skoog (MS) medium with 3 mg l−1 α-naphthalene acetic acid and later transferred to MS without growth regulators (MSWH). Samples of zygotic embryo cotyledons (explants), of globular and dicotyledonar somatic embryos, and of embling leaves were
analysed for reserve accumulation and histocytological profiles. Cotyledon cells of zygotic embryos were rich in lipid and
protein bodies, having almost no starch. After 3 weeks of induction, starch grain density increased in differentiated mesophyll
regions, while in meristematic regions their occurrence was diffuse. In globular somatic embryos, starch accumulation increased
with time (in amyloplasts), but protein bodies were absent. Cotyledonary somatic embryos had lower density of starch grains
and absence of lipid and protein bodies. Embling leaves showed typical histological organisation. This is the first comprehensive
study on histological and cytological changes during Eucalyptus SE with emphasis in reserve accumulation. With this work we demonstrate that the presently available SE protocol for E. globulus leads to reserve fluctuations during the process. Moreover, the reserves of somatic embryo cotyledons differ from those of
their zygotic embryo counterparts, which reinforce the importance of reserves in the embryogenic process and suggests that
manipulating external conditions, SE may be optimised giving suitable emblings production for industrial purposes. 相似文献
3.
Mohammed A. M. Aly Essam A. Amer Wasef A. Al-Zayadneh Alaa E. Negm Eldin 《Plant Cell, Tissue and Organ Culture》2008,95(1):107-114
Inducing somatic embryogensis from jojoba [Simmondsia chinensis (Link) Schneider] explants to produce artificial seeds in the laboratory (in vitro) may prove highly profitable, as the seeds
contain a characteristic liquid wax of economic importance in industry, nutrition and medicine. Thus, there is a need to examine
the effect of the factors involved in the in vitro process on the quality and quantity of the synthesized fatty acids in comparison
with those naturally produced in vivo. Immature zygotic embryos and mature leaf explants were cultured on Murashige and Skoog
basal medium (MS) supplemented with various levels of 2,4-D, BA and sucrose. Embryogenic calluses developed from the zygotic
embryos and leaf explants over a period of 2–4 weeks with the highest response at 0.4 μM 2,4-D, 2.2/4.4 μM BA and 117 mM sucrose
(4%). Following induction, the zygotic embryo derived somatic embryos developed to the globular, heart, torpedo, and cotyledon
stages. Direct somatic embryogenesis was observed with some of the zygotic embryo explants. Leaf-derived embryogenic calluses
did not mature on any of the maturation/germination media examined up to 4 weeks of culture. Analysis of fatty acids indicated
that the mature seeds are characterized with long chain saturated fatty acids C22:0 behenic Acid. The zygotic embryo-derived
somatic embryos (SE-Z) and leaf-derived somatic embryos (SE-L) are characterized with the induction of the essential polyunsaturated
fatty acid C18:2 (omega-6) linoleic acid, (omega-3) alpha-linolenic acid (ALA), with higher values of long chain saturated
fatty acids C16:0 palmitic acid and monounsaturated fatty acid C18:1 oleic acid. These results indicate that manipulating
the growth regulators in the induction media influenced the fatty acids synthesis and hence the fatty acids profile in jojoba
somatic embryos. 相似文献
4.
5.
In vitro somatic embryogenesis in two major rattan species: Calamus merrillii and Calamus subinermis
D. K. S. Goh M. -C. Bon F. Aliotti J. Escoute N. Ferrière O. Monteuuis 《In vitro cellular & developmental biology. Plant》2001,37(3):375-381
Summary Occurrence of somatic embryogenesis in in vitro cultures of Calamus merrillii and Calamus subinermis, two major largecaned rattan species, was scientifically demonstrated for the first time. Tissue responsiveness varied markedly
according to the species and the type of primary explants used when initiated on 10.4–31.2 μM picloram-enriched Murashige and Skoog callus induction media. In C. merrillii, within 6 wk after inoculation, 84% of the leaf and 90% of the zygotic embryo explants produced friable embryogenic calluses,
by contrast with those formed by 74% of the root explants. In C. subinermis, callogenesis was observed only 6 mo. after inoculation in 68% of root and 48% of zygotic explants. Leaf explants did not
respond at all. Only root-derived calluses developed into nodular embryogenic structures. Irrespective of these initial differences,
the further steps of the somatic embryogenesis developmental pattern was similar for both species. Histological analyses established
that callus formation took place in the perivascular zones, and could give rise to embryogenic isolated cells from which the
proembryos were derived. Reducing the picloram concentration stimulated the maturation process resulting ultimately in the
germination of somatic embryos that exhibited bipolar development, despite an apparent lack of starch and protein reserves.
The somatic embryo-derived plantlets of C. merrillii, overall more prone to somatic embryogenesis than C. subinermis in the given conditions, were successfully acclimatized to outdoor conditions. 相似文献
6.
M. T. Pérez-Núñez J. L. Chan L. Sáenz T. González J. L. Verdeil C. Oropeza 《In vitro cellular & developmental biology. Plant》2006,42(1):37-43
Summary Coconut is one of the most recalcitrant species to regenerate in vitro. Although previous research efforts using plumule explants have resulted in reproducible somatic embryogenesis, efficiency
is only 4 or 10 somatic embryos per plumule without or with a brassinolide treatment, respectively. In order to increase the
efficiency of somatic embryogenesis in coconut, two different approaches were evaluated and reported here: secondary somatic
embryogenesis and multiplication of embryogenic callus. Primary somatic embryos obtained from plumule explants were used as
explants and formed both embryogenic callus and secondary somatic embryos. The embrogenic calluses obtained after three multiplication
cycles were capable of producing somatic embryos. The efficiency of the system was evaluated in a stepwise process beginning
with an initial step for inducing primary somatic embryogenesis followed by three steps for inducing secondary somatic embryogenesis
followed by three steps for embryogenenis callus multiplication, and finally production of somatic embryos from callus. The
total calculated yield from one plumule was 98 000 somatic embryos. Comparing this to the yield obtained from primary somatic
embryogenesis results in about a 50 000-fold increase. When compared to the yield previously reported in the literature with
the use of a brassinolide treatment, it is about a 10 000-fold increase in yield. The present protocol represents important
progress in improvement in the efficiency of coconut somatic embryo production. 相似文献
7.
Hugo Teixeira Gomes Patrícia Monah Cunha Bartos Jonny Everson Scherwinski-Pereira 《Plant Cell, Tissue and Organ Culture》2017,131(2):269-282
Oil palm is an economically important plant species due to its high oil production per unit area. Large-scale clonal propagation of the species’s elite specimens is only possible through somatic embryogenesis, although methodology is partially still unknown and insufficiently understood. Current study characterizes in morphological and anatomical terms the acquisition and development stages of somatic embryogenesis of the oil palm’s immature leaves. The respective embryogenic stages were analyzed and characterized: immature leaves (initial explants); leaves with calli formation; leaves which failed to respond to calli formation; leaves with formation of root structures; primary calli; primary calli with differentiation of embryogenic calli; embryogenic calli; pro-embryogenic calli; calli with differentiated somatic embryos; somatic embryos at globular and torpedo stage; and mature fruit zygotic embryos. Cell masses emerged after approximately 60 days of cultivation through the proliferation of cells associated to initial explants´ vascular bundles. Consequently, the formation of two different types of calli was identified, namely, primary and embryogenic, respectively consisting partially and completely of meristematic cell clusters. After 420 days of cultivation, the propagules formed somatic embryos with no connection to source tissues, initially composed (globular stage) of a very characteristic ground meristem and protoderm. After 480 days of cultivation, as the cultures matured (torpedo stage), procambial strands, a structural characteristic also observed in mature zygotic embryos, were reported. The results provide an in-depth understanding of somatic embryogenesis of immature leaves of oil palm. Further, current analysis develops morphological markers at different stages of development obtained during the process. 相似文献
8.
Improvement on rice plant regeneration system from an embryogenic callus using two Malaysian indica rice MR 219 and MR 232
was developed in this study. Different stages of rice explants (zygotic embryos) were tested for callus induction and regeneration
using various carbon sources and amino acids. The present study shows that dough stage of zygotic embryos was the best stage
of explants for the embryogenic callus induction and regeneration of both rice cultivars. The embryogenic callus nature with
the compact structure was confirmed by scanning electron microscopy (SEM) analysis. Inclusion of maltose at the concentration
between 10 and 20 mg/L shown higher responsive for the development of green somatic embryos and initiation of rice regeneration
with an average of 29–37 (87–91%) regenerated plantlets, respectively. All in vitro regenerated rice plantlets were green,
morphological and physiologically healthy condition. Rice plantlets were hardened in acclimatization room for 3 weeks and
later transferred into soil with 95% survival in both varieties were recorded. Hence, regeneration system from zygotic rice
embryos via somatic embryogenesis system was carried out successfully by using 10 g/L of maltose and combinations of glutamine,
asparagine and arginine amino acids. 相似文献
9.
Hypocotyl segments (HS) of flax seedlings germinated in vitro, were used to induce indirect somatic embryogenesis on solid medium. The composition and distribution of n-alkanes in flax tissues collected at different developmental stages were studied by capillary gas chromatography (GC) and capillary gas chromatography-mass spectrometry (GC-MS). During induction and development of callus from hypocotyl tissues a decrease in the percentage of total lipids was observed. In all types of tissue sampled – HS used as primary explants, HS with differentiating calli at the cut ends (HSC), embryogenic (EC) and non-embryogenic calli (NEC) and somatic embryos (SE) – a skewed-normal distribution of n-alkanes with a low mass range (C13–C21) were found. The highest content of n-alkanes occurred in the primary hypocotyl explants and in the early stages of callus development. Longer carbon chain n-alkanes were observed only in the mature or differentiated tissues of hypocotyls and SE. Although the n-alkane contents decreased with time, in SE and calli, a significantly lower n-alkane content was observed in EC when compared to NEC independent of the time in culture. These results suggest the utilisation of n-alkanes for heterotrophic cellular growth as well as its mobilisation from EC to developing SE. 相似文献
10.
为探讨花榈木体胚发生过程中不同碳氮源处理对胚性愈伤组织诱导、发育和有机物积累的影响,并筛选出有利于花榈木体胚发生的碳氮源,优化体胚发生体系,该研究以成熟胚为外植体,通过单因素试验分析3种碳源、4种蔗糖浓度和6种氮源处理下胚性愈伤组织诱导、发育和有机物积累的差异。结果表明:(1)蔗糖中胚性愈伤组织诱导率显著高于葡萄糖和麦芽糖,但其体胚诱导率、体胚分化率、胚性愈伤组织可溶性糖、淀粉和可溶性蛋白含量差异不显著。(2)随着蔗糖浓度的升高,胚性愈伤组织、体细胞胚(体胚)诱导率、体胚分化率、胚性愈伤组织重量和可溶性蛋白含量呈先升高后降低的趋势,均以添加30 g·L-1蔗糖最高,而胚性愈伤组织可溶性糖和淀粉含量呈增加的趋势。(3)在6种氮源处理中,胚性愈伤组织诱导率以添加500 mg·L-1谷氨酰胺的处理最高,体胚诱导率则以添加谷氨酰胺和水解酪蛋白的处理较高,但不同氮源处理间体胚分化率无差异;添加有机氮源的处理其胚性愈伤组织可溶性蛋白含量显著高于无氮源处理。总之,不同的碳氮源通过影响花榈木胚性愈伤组织的诱导、发育和有机物的积累,从而影响其体胚诱导率,但对体... 相似文献
11.
The analysis of differential gene expression in early somatic embryogenesis on Lycium barbarum 总被引:3,自引:0,他引:3
Kairong Cui Gengsheng Xing Lin Qin Xinmin Liu Yafu Wang 《Plant Cell, Tissue and Organ Culture》1999,59(3):169-174
Direct exposure of calluses of Lycium barbarum L. to an auxin-free medium can induce somatic embryogenesis. Somatic
embryogenesis of Lycium barbarum L. is controlled artificially by regulating 2,4-D concentration. The total RNA that was isolated from calluses, embryonic
calluses and early somatic embryos was used for analyzing differential genes expression. We obtained three cDNAs from early
somatic embryogenesis which were not found in calluses. The results indicate that these cDNAs were early embryogenesis-specific
cDNAs and this gene expression was induced in cultured calluses after a transfer to an auxin- free medium. A cDNA library
was constructed using poly(A)+-RNA derived from early somatic embryos of Lycium barbarism L. Two full-length cDNAs were isolated from the library by differential screening. Northern blot hybridization analysis indicated
that the expression of the full-length cDNA only existed in embryogenic calluses and early somatic embryos of Lycium barbarum L.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
12.
Somatic embryogenesis can be induced in tissue cultures of Freesia refracta either directly from the epidermal cells of explant, or indirectly via intervening callus. In direct pathway, somatic embryos were in contact with maternal tissue in a suspensor-like structure. In indirect pathway, the explants first proliferacted to give rise to calluses before embryoids were induced. The two sorts of calluses were defined to embryogenic callus and non-embryogenic callus according to producing of somatic embryos. An indirect somatic embryo is developed from a pre-embryogenically determined cell. This kind of somatic embryo has no suspensor structure instead of a complex with maternal tissue. Somatic embryos have their own vascular tissues, and can develop new plantlets independently. 相似文献
13.
Ananya Paul Kalyan Mitter Sarmistha Sen Raychaudhuri 《Plant Cell, Tissue and Organ Culture》2009,97(3):303-311
The effects of exogenous polyamines (PAs) on enhancement of somatic embryogenic calli was investigated in Momordica
charantia L. in vitro. Induction of somatic embryogenesis (SE) in leaf explants of M. charantia after 21 days of culture in Murashige and Skoog (MS) medium was determined using scanning electron microscopy. During induction
of SE there were high titers of Putrescine (Put) as compared to Spermidine (Spd) and Spermine (Spm), a prerequisite for cell
division. Addition of PAs to the embryogenic media resulted in an increase in fresh weights and number of somatic embryos
of 21-day old embryogenic calli. Put at a concentration of 1 mM showed maximum increase in fresh weights of embryogenic calli
(5 fold) and number of somatic embryos produced per 0.2 g of callus (2.5 fold). Moreover addition of PAs to the embryogenic
media resulted in lowering of endogenous free PA level of 21-day old embryogenic calli. Thus, when the media was supplemented
with exogenous PAs a positive correlation was found to exist between Somatic Embryogenesis enhancement and decrease in endogenous
free PA levels. 相似文献
14.
香果树体细胞胚胎发生过程中4种同工酶的研究 总被引:5,自引:1,他引:4
用非变性聚丙烯凝胶电泳技术对香果树体细胞胚胎发生及形态建成过程中过氧化物酶(POD)、酯酶(EST)、淀粉酶(AMY)和超氧化物歧化酶(SOD)4种同工酶进行分析.结果表明:香果树体细胞胚胎发生及形态建成过程中,POD、EST、AMY和SOD活性变化与胚性愈伤组织的诱导及体细胞胚的发生发育密切相关.非胚性愈伤组织和胚性愈伤组织酶谱差异明显,胚性愈伤组织中EST和AMY同工酶酶带多且活性高,非胚性愈伤组织中缺乏EST和AMY同工酶表达,AMY同工酶可作为胚性细胞分化和发育的重要标志.香果树体细胞胚形态建成过程中,球形胚时期的AMY、POD、EST同_T酶活性最强,表明这一时期生理代谢旺盛,是体细胞胚形态建成的关键时期;POD、AMY和SOD 3种同工酶的酶谱及表达强弱在形态建成的不同时期呈现有规律的变化,可作为香果树体细胞胚发生发育特定时期的参考标记. 与胚性愈伤组织的诱导及体细胞胚的发生发育密切相关.非胚性愈伤组织和胚性愈伤组织酶谱差异明显,胚性愈伤组织中EST和AMY同工酶酶带多且活性高,非胚性愈伤组织中缺乏EST和AMY同工酶表达,AMY同工酶町作为胚性细胞分化和发育的重要标志.香果树体细胞胚形态建成过程 ,球形胚时期的AMY、POD、EST同_T酶活性最强,表明这一时期生理代谢旺盛,是体细胞胚形态建成的关键时期;POD、AMY和SOD 3种同工酶的酶谱及表达强弱在形态建成的不同时期呈现有规律的变化,可作为香果树体细胞胚发生发育特定时期的参考标记. 与胚性愈伤组织的诱导及体细胞胚的发生发育密切相关.非胚性愈伤组织和胚性愈伤组织 相似文献
15.
香雪兰的体细胞胚胎发生可通过两种途径进行,即直接发生与间接发生。在直接发生方式中,体细胞胚直接来源于尚未完全分化的外植体表皮细胞;体细胞胚与母体组织以一种类似胚柄的结构相联系。间接发生方式中,体细胞胚的形成要经过一个愈伤组织阶段。以是否能形成体细胞胚分类,可将愈伤组织分为胚性和非胚性愈伤组织。以间接方式形成的体细胞胚是由胚性愈伤组织中的一种决定细胞发育来的。这种体细胞胚不具有类似胚柄的结构,而与母体组织共同形成一个复合体。体细胞胚具有自己独立的维管束系统,在脱离母体组织后能够独立发育成株。 相似文献
16.
Tasiu Isah 《Acta Physiologiae Plantarum》2016,38(5):118
Somatic embryogenesis, the in vitro developmental program by which somatic cells are reprogrammed to undergo cellular and molecular changes that make them competent to produce somatic embryos, has been achieved with many woody plants. The program involves the stages of competence acquisition, induction and expression of the morphogenic pathway by the cultured cells and tissues. The ability to express the program in cultured cells/tissues is regulated by many factors, including genotype, explant type and age and culture conditions. In many woody plants, somatic embryogenesis was achieved with mature, immature explants or both. Juvenile tissues as immature and mature zygotic embryos are regarded best explants to establish embryogenic cultures in woody plants and potential to obtain the cultures decline with increasing maturity of the explant. 相似文献
17.
Jasmonic acid (JA), its methyl ester (MeJA) and the biosynthetic precursor 12-oxophytodienoic acid (OPDA) were detected quantitatively
during somatic embryogenesis of Medicago sativa L. Using GC-MS analysis, these compounds were found in initial explants, in calli and in somatic embryos in the nanogram
range per gram of fresh weight. In distinct stages of somatic embryogenesis, JA and 12-OPDA accumulated preferentially in
cotyledonary embryos. Initial explants exhibited about five-fold higher JA content than OPDA content, whereas in other stages
OPDA accumulated predominantly. These data suggest that also in embryogenic tissues OPDA and JA may have individual signalling
properties. 相似文献
18.
Chun-Lai Zhang Dong-Fang Chen Marie Kubalakova Jian Zhang Nigel W. Scott Malcolm C. Elliott Adrian Slater 《Plant Cell, Tissue and Organ Culture》2008,93(2):209-221
Efficient regeneration via somatic embryogenesis (SE) would be a valuable system for the micropropagation and genetic transformation
of sugar beet. This study evaluated the effects of basic culture media (MS and PGo), plant growth regulators, sugars and the
starting plant material on somatic embryogenesis in nine sugar beet breeding lines. Somatic embryos were induced from seedlings
of several genotypes via an intervening callus phase on PGo medium containing N6-benzylaminopurine (BAP). Calli were mainly induced from cotyledons. Maltose was more effective for the induction of somatic
embryogenesis than was sucrose. There were significant differences between genotypes. HB 526 and SDM 3, which produced embryogenic
calli at frequencies of 25–50%, performed better than SDM 2, 8, 9 and 11. The embryogenic calli and embryos produced by this
method were multiplied by repeated subculture. Histological analysis of embryogenic callus cultures indicated that somatic
embryos were derived from single- or a small number of cells. 2,4-dichlorophenoxyacetic acid (2,4-D) was ineffective for the
induction of somatic embryogenesis from seedlings but induced direct somatic embryogenesis from immature zygotic embryos (IEs).
Somatic embryos were mainly initiated from hypocotyls derived from the cultured IEs in line HB 526. Rapid and efficient regeneration
of plants via somatic embryogenesis may provide a system for studying the molecular mechanism of SE and a route for the genetic
transformation of sugar beet. 相似文献
19.
Glória Pinto Helena Valentim Armando Costa Sílvia Castro Conceição Santos 《In vitro cellular & developmental biology. Plant》2002,38(6):569-572
Summary Somatic embryos were obtained from a 60-yr-old Quercus suber L. tree. Leaf explants were cultivated on Murashige and Skoog medium with 30 gl−1 sucrose, 3 gl−1 gelrite, pH adjusted to 5.8, and different growth regulator combinations. Callus induction took place at 24±1°C in the dark
during the first 3 wk. After 3 mo, calluses that showed embryogenic structures were transferred to the same medium without
growth regulators. Somatic embryogenesis was only observed in calluses induced on E3 medium (supplemented with 4.5 μM 2,4-dichlorophenoxyacetic acid and 9.0 μM zeatin). On average, 7.5% of the initial explants formed embryogenic calluses in this medium. Somatic embryo proliferation
was high due to secondary embryogenesis. On average, 10% of the somatic embryos germinated and 40% of these germinated embryos
converted into plants. Plants were elongated on the same medium without growth regulators and acclimated to greenhouse conditions. 相似文献
20.
Patrícia Monah Cunha Bartos Hugo Teixeira Gomes Sueli Maria Gomes Sebastião Carvalho Vasconcelos Filho João Batista Teixeira Jonny Everson Scherwinski-Pereira 《Biologia》2018,73(12):1255-1265
The objective of this study was to characterize the histodifferentiation of somatic embryogenesis obtained from leaf explants of C. arabica. Therefore, we histologically analyzed the respective stages of the process: leaf segments at 0, 4, 7, 15 and 30 days of cultivation, Type 1 primary calli (primary calli with embryogenic competence) and 2 (primary calli with no embryogenic competence), embryogenic calli, globular, torpedo and cotyledonary embryos, and mature zygotic embryos. Callus formation occurred after seven days of culture, with successive divisions of procambium cell. In this cultivation phase, it was found that Type 1 primary calli are basically formed by parenchymal cells with reduced intercellular spacing, whereas Type 2 primary calli are predominantly composed of parenchymal cells with ample intercellular spaces and embryogenic calli composed entirely of meristematic cells. After 330 days, it was evident from the differentiation of somatic embryogenesis that there was formation of globular somatic embryos, consisting of a characteristic protoderm surrounding the fundamental meristem. With the maturation of these propagules after 360 days, torpedo-stage somatic embryos arose, in which tissue polarization and early differentiation of procambial strands were verified. After 390 days, cotyledonary somatic embryos were obtained, where the onset of vessel elements differentiation was verified, a characteristic also observed in mature zygotic embryos. We concluded that somatic embryogenesis obtained from C. arabica leaves initiates from procambium cell divisions that, in the course of cultivation, produce mature somatic embryos suitable for regenerating whole plants. 相似文献