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1.
An efficient method for the in vitro propagation of a tea (Camellia sinensis (L) O. Kuntze) clone, `TRI-2025', from somatic embryos is described. This technique involves two phases; the induction of
adventitious buds from nodal cuttings followed by the development of somatic embryos. Single nodal cuttings were excised from
1-year-old in vitro axenic cultures and inoculated on MS medium with different combinations of IBA/BAP/GA3. Induction of multiple shoots from nodal explants occurred on MS medium with 0.5 mg l–1 BAP, 0.1 mg l–1 IBA and 0.0 mg l–1 GA3 within 6 weeks of incubation. The cultures with multiple shoots were transferred to fresh medium, incubated for 120 days
and transferred to MS medium with half-strength macro nutrients, full-strength micronutrients and vitamins and no growth regulator.
The direct induction of somatic embryos without callus formation occurred on this medium at 60% frequency within 4 weeks.
The production of embryos continued upon transfer of the cultures to fresh medium and a four- to eightfold multiplication
rate was obtained during each 6-week culture cycle. The plantlets from these embryos were acclimatised with a 90% success
rate. All plants were vigorous and hardy, with well-developed tap-root systems.
Received: 20 July 1996 / Revision received: 2 January 1998 / Accepted: 19 January 1998 相似文献
2.
Plant regeneration via somatic embryogenesis was achieved in callus cultures derived from nodal explants of in vitro grown seedlings and excised mature zygotic embryos of three bamboo species on Murashige and Skoog's (MS) basal medium supplemented with 0.5 mg/l kinetin (Kn), 2.0 mg/l 2,4-dichlorophenoxyacetic acid (2,4-D), 10 mg/l adenine sulphate (Ads) and 3% (w/v) sucrose incubated in the light or in the dark. Somatic embryos germinated (95–98%) into normal plants and were transferred to soil with 95% success. In vitro flowering was induced on shoots developed from nodal explants taken from somatic embryo regenerated plants of Bambusa vulgaris, Dendrocalamus giganteus and Dendrocalamus strictus on half-strength MS basal medium supplemented with 0.25 mg/l indole-3-butyric acid (IBA), 0.5 mg/l Ads, 0.5 mg/l gibberellic acid (GA3) and 3% sucrose.Abbreviations BAP
6-benzylaminopurine
- Kn
kinetin
- Ads
adenine sulphate
- IBA
indole-3-butyric acid
- NAA
1-naphthaleneacetic acid
- 2,4-D
2,4-dichlorophenoxyacetic acid
- MS
Murashige and Skoog (1962) basal medium
- GA3
gibberellic acid 相似文献
3.
A protocol has been developed for achieving somatic embryogenesis from callus derived from nodal cuttings and production of synthetic seeds in Hemidesmus indicus L. R. Br. a highly traded ethnomedicinal plant. Proembryogenic, friable, light yellowish callus was induced from the basal cut end of the nodal cuttings on Murashige and Skoog (MS) medium supplemented with 3 μM indole-3-butyric acid (IBA). The highest rate of somatic embryogenesis (92 %) was observed when the callus was subcultured on half strength MS medium supplemented with 2 μM IBA. On induction medium somatic embryos were developed up to the torpedo stage. Further elongation and germination of somatic embryos were obtained in MS medium supplemented with 4 μM 6-benzylaminopurine (BA) in combination with 1.5 μM gibberellic acid (GA3). Somatic embryos were collected and suspended in a matrix of MS medium containing sodium alginate (3 % W/V) dropped into 75 mM calcium chloride (CaCl2·2H2O) solution for the production of synthetic seeds and later transferred to MS medium for germination. The synthetic seeds were successfully germinated on medium even after 120 days of storage at 4 °C. The plantlets were eventually transferred to soil with 92 % success. 相似文献
4.
The morphogenetic potential of node, internode and leaf explants of Brahmi [Bacopa monniera (L.) Wettst.] was investigated to develop reliable protocols for shoot regeneration and somatic embryogenesis. The explants
were excised from shoots raised from axillary buds of nodal explants cultured on Murashige and Skoog (MS) basal medium. Presence
of 6-benzylaminopurine (BA) or kinetin influenced the degree of callus formation, from which a large number of shoot buds
regenerated. Leaf explants gave the largest number of shoot buds followed by node and internode explants. BA was superior
to kinetin; BA at 1.5 – 2.0 mg/l appeared to be optimum for inducing the maximum number of shoot buds. MS + 0.1 mg/l BA +
0.2 mg/l indole-3-acetic acid was the most suitable for shoot elongation. Elongated shoots were rooted on full- or half-strength
MS medium with or without 0.5 – 1.0 mg/l indole-3-butyric acid or 0.5 – 1.0 mg/l α-naphthaleneacetic acid. The rooted plants were successfully established in soil. Calli derived from nodal explants cultured
on MS medium containing 0.5 mg/l 2,4-dichlorophenoxyacetic acid (2,4-D), when subcultured on MS medium containing 0.1 or 0.5
mg/l BA or 0.2 mg/l 2,4-D + 0.1 or 0.5 mg/l kinetin, developed somatic embryos. The somatic embryos germinated either on the
same media or on MS basal medium, and the resulting plantlets were successfully transplanted to soil.
Received: 25 September 1996 / Revision received: 23 October 1997 / Accepted: 12 November 1997 相似文献
5.
Summary Efficient and highly reproducible induction of somatic embryogenesis was obtained in four out of seven selected clones of
neem, Azadirachta indica A. Juss. This was achieved either directly from root and nodal explants or indirectly from callus cultures initiated from
leaf explants excised from 1-yr-old axenic plants. Direct induction of somatic embryogenesis was achieved both from nodal
and root segments within 8 wk of culture on MS1 medium without growth regulators. However, the addition of 2.3–4.5 μM thidiazuron and 0.5 μM 2,4-dichlorophenoxyacetic acid into the medium were necessary to induce somatic embryogenesis via callus phase from leaf
explants. Repetitive embryogenesis was observed within 3–4 wk following transfer of somatic embryos to a plant growth regulator-free
medium. When somatic embryos of nodal and root segments were left on the induction medium without subculturing, approximately
15% of the somatic embryos developed into whole plantlets after passing through a series of developmental stages. Plantlets
thus produced were hardy, lush green, and acclimatized casily under greenhouse conditions. However, somatic embryos derived
from leaf explants showed low conversion rates (<5%). HPLC analysis revealed no detectable levels of azadirachtin in somatic
embryos. 相似文献
6.
Somatic embryogenesis was obtained from cotyledon and mature zygotic embryo callus cultures of Terminalia chebula Retz. Callus cultures of cotyledon and mature zygotic embryo were initiated on induction medium containing Murashige and Skoog (MS) nutrients with 1.0 mg/l 2,4-dichlorophenoxyacetic acid (2,4-D) either 0.01 or 0.1 mg/l Kinetin and 30 g/l sucrose. Induction of somatic embryogenesis, proliferation and development was obtained through different culture passages. Embryogenic cotyledon callus with globular somatic embryos was obtained on MS basal medium supplemented with 50 g/l sucrose. Globular somatic embryos were observed from mature zygotic embryo callus on induction medium. Different stages of somatic embryo development from cotyledon and mature zygotic embryo calluses were observed on MS basal medium supplemented with 50 g/l sucrose after 4 weeks of culture. Histological studies have revealed the developmental stages of somatic embryos. A maximum of 40.3±1.45 cotyledonary somatic embryos/callus was obtained from mature zygotic embryo compared to 7.70±0.37 cotyledonary somatic embryos/callus initiated from cotyledons. Germination of somatic embryos and conversion to plants were achieved. Highest frequency of germination (46.66±0.88) of somatic embryos was obtained on MS basal medium containing benzyladenine (0.5 mg/l) with 30 g/l sucrose. 相似文献
7.
Spontaneous recovery of regeneration abilities was observed in a long-term (about two-year-old) crownvetch (Coronilla varia L.) tissue culture permanently grown on MS medium containing 1 mg 1-1 IAA. Somatic embryos and later complete plants differentiated from initially regenerating roots. The formation and development
of embryos was accompanied by a 10- to 20-fold increase in the content of cardioactive glycosides hyrcanoside and deglucohyrcanoside
in the culture biomass. The effect of auxins (IAA, NAA, 2,4-D) and cytokinins (6-BAP) on calogenesis and somatic embryogenesis
was examined; further development of somatic embryos was enhanced by light. Primary explants which were newly isolated from
sterile R1 plantlets showed differential, organ-specific ability of somatic embryogenesis which was highest in root cuttings. Regenerated
plants were transferred to field culture; two-year-old cultures of regenerated plants showed in most cases phenotypic deviations
from the original material, especially dwarfism. 相似文献
8.
High-efficiency somatic embryogenesis and plant regeneration from suspension cultures of grapevine 总被引:10,自引:0,他引:10
Embryogenic suspensions of grapevine (Vitis vinifera L.) were initiated from somatic embryos of `Thompson Seedless' and `Chardonnay'. Suspension cultures consisted of proembryonic
masses (PEM) that proliferated without differentiation in a medium containing 2,4-dichlorophenoxyacetic acid (2,4-D). `Chardonnay'
somatic embryos developed fully from PEMs following subculture in medium without 2,4-D; however, somatic embryo development
did not advance beyond the heart stage in `Thompson Seedless' suspension cultures. Highly synchronized development of somatic
embryos was obtained by inoculating <960-μm PEMs into liquid medium without 2,4-D. Somatic embryos were also produced in large
numbers from suspension-derived PEMs of both cultivars on semisolid medium lacking 2,4-D. Somatic embryos matured and regenerated
into plants in MS basal medium containing 3% sucrose. Using this method more than 60% of the somatic embryos regenerated plants.
More than 90% of the regenerated plants were successfully transferred to the greenhouse.
Received: 27 July 1998 / Revision received: 15 October 1998 / Accepted: 27 October 1998 相似文献
9.
Effect of thidiazuron on vegetative tissue-derived somatic embryogenesis and flowering of bamboo Bambusa edulis 总被引:1,自引:0,他引:1
Current research on somatic embryogenesis of bamboo uses reproductive tissue as explants. However, it was hard to obtain the explant. Shoots of a local accession (3–4 m high) were used for multiple shoot production. In order to obtain embryogenic callus, nodal and internodal tissues from in vitro plantlets were placed on Murashige and Skoog (MS) medium supplemented with 9.2 M kinetin (KN), 13.6 M 2,4-dichlorophenoxyacetic acid (2,4-D), 0.1% (v/v) coconut milk, and 6% (w/v) sucrose. We studied the effects of sucrose and thidiazuron (TDZ) on callus proliferation. Optimal additives to the MS medium for embryogenic callus proliferation were 0.046 M TDZ, 13.6 M 2,4-D and 3% (w/v) sucrose. TDZ also promoted the germination of bamboo somatic embryos. The germination rate of the somatic embryos exceeded 80% on MS-based medium supplemented with 0.455M TDZ. Naphthaleneacetic acid (NAA) reduced germination. Well-developed plantlets were successfully transferred to soil. There was no albino mutant in subsequent culture. In vitro regenerants and potted plants flowered, but no seeds were produced. 相似文献
10.
Direct regeneration of somatic embryos was obtained from immature zygotic embryos of Dalbergia latifolia. Immature embryos dissected from green pods 90 d after flowering gave the highest frequency of somatic embryo formation. Preculture on high 2,4-D medium for 4 weeks induced direct somatic embryogenesis, which was expressed during the second culture phase in the presence of low 2,4-D along with a high sucrose concentration. Embryos were separated and transferred to the maturation medium containing MS + 0.5–1.0 mg/L BAP, where embryos developed into plantlets. Somatic embryos failed to convert into complete plants without BAP treatment. This method of direct regeneration of somatic embryos without a callus phase has direct application for genetic manipulation studies.Abbreviations MS
Murashige and Skoog (1962) medium
- 2,4-D
2,4-Dichlorophenoxyacetic acid
- BAP
6-benzylaminopurine
- ABA
Abscisic acid
- KIN
Kinetin 相似文献
11.
Chellappan Soundar Raju Krishnan Kathiravan Abubakker Aslam Appakan Shajahan 《Plant Cell, Tissue and Organ Culture》2013,112(3):387-393
A reproducible protocol for somatic embryogenesis was established for mango ginger (Curcuma amada Roxb.)—an important horticultural aromatic rhizomatous plant. Embryogenic callus induction was obtained from leaf sheath explants of in vitro raised plants on Murashige and Skoog (MS) agar medium containing 2.0 mg/L 2,4-dichlorophenoxyacetic acid and 0.5 mg/L 6-benzyladenine (BA). Embryogenic callus proliferation, somatic embryo (SE) formation and subsequent plantlet conversion occurred under optimal culture conditions. The effects of MS medium strength, sucrose and BA on SE formation were also evaluated. Half strength MS liquid medium necessary for SE formation and optimal sucrose concentration was found to be 3.0 %. BA at 0.3 mg/L produced the highest number (84.71 %) of SEs from leaf sheath explants. Secondary somatic embryos originated from primary somatic embryos on the same medium supplemented with 0.4–0.6 mg/L BA. Stereo microscopic and scanning electron microscopic observation revealed that the globular and torpedo shaped somatic embryos resulted in suspension culture during development. Mature somatic embryos germinated readily and developed into normal plantlets after 3 weeks on half strength MS basal agar medium under dark condition. Well rooted plantlets were successfully acclimatized at the survival rate of 70 %. 相似文献
12.
Summary
In vitro regeneration of plants via somatic embryogenesis through cell suspension culture was achieved in horsegram. Embryogenic calluses
were induced on leaf segments on solid Murashige and Skoog (MS) medium with 9.0 μM 2,4-dichlorophenoxyacetic acid (2,4-D). Differentiation of somatic embryos occurred when the embryogenic calluses were transferred
to liquid MS medium containing 2,4-D. Maximum frequency (33.2%) of somatic embryos was observed on MS medium supplemented
with 7.9 μM 2,4-D. Cotyledonary-torpedo-shaped embryos were transferred to liquid MS medium without growth regulators for maturation
and germination. About 5% of the embryos germinated into plants, which grew further on solid MS medium. The plants were hardened
and established in soil. Effects of various auxins, cytokinins, carbohydrates, amino acids, and other additives on induction
and germination of somatic embryos were also studied. A medium supplemented with 7.9 μM 2,4-D, 3.0% sucrose, 40 mg l−1
L-glutamine, and 1.0 μM abscisic acid was effective to achieve a high frequency of somatic embryo induction, maturation, and further development. 相似文献
13.
Ning Zhang Wei Fang Yan Shi Qianqian Liu Haiyun Yang Renyi Gui Xinchun Lin 《Plant Cell, Tissue and Organ Culture》2010,103(3):325-332
In this study, mature zygotic embryos, plant growth regulators, and various media were tested with the aim of developing an efficient regeneration system for plantlets of the bamboo species Dendrocalamus hamiltonii. Callus formation was induced in explants cultured in Murashige and Skoog (MS) medium supplemented with 1.0–3.0 mg/l 2,4-dichlorophenoxyacetic acid. Optimal shoot differentiation and subsequent shoot growth were also obtained in MS medium supplemented with 2 mg/l benzyladenine, 1 mg/l kinetin, and 1 mg/l naphthaleneacetic acid. Root induction was enhanced by the addition of 5 mg/l indole-3-butyric acid to the culture medium. Histological analysis revealed that both somatic embryogenesis and organogenesis were induced during callus initiation, shoot differentiation, and the development of plantlets from the mature zygotic embryos. Our data provide a useful basis for developing culture protocols for the regeneration of bamboo plants. 相似文献
14.
Somatic embryo formation and germination from immature embryo-derived suspension-cultured cells of Angelica sinensis (Oliv.) Diels 总被引:3,自引:0,他引:3
Embryogenic callus was induced from immature embryos of Angelica sinensis cultured on Murashige and Skoog (MS) basal medium. Embryogenic callus growth was more rapid on MS basal medium than on B5
or White medium. Embryogenic callus was used to establish a suspension culture and somatic embryos and germinating embryos
developed during the culture. A shaking speed of 80 rpm was found to be optimal for establishing suspension cultures, while
100 rpm produced more somatic embryos and germinating embryos with an initiation cell density of 0.2 ml packed cell volume/25
ml medium. Adding 0.3% agar to the liquid medium also stimulated the formation of somatic and germinating embryos. While no
plant growth regulators were needed for culture initiation and plant regeneration, the addition of 0.5–1 mg/l 2,4-dichlorophenoxyacetic
acid was needed to maintain the embryogenic suspension culture by preventing embryo germination. Forty percent of the germinating
embryos survived after culturing on filter paper moistened with liquid half-strength MS medium containing 3% sucrose. The
plants were successfully transferred into soil.
Received: 19 March 1997 / Revision received: 21 November 1997 / Accepted: 19 January 1998 相似文献
15.
An efficient in vitro plant regeneration system characterized by rapid and continuous production of somatic embryos using leaf and petiole expiants has been developed in sweetpotato [Ipomoea batatas L. (Lam.)]. The optimal somatic embryogenic response was obtained in the genotype PI 318846-3 with a two-step protocol: (1) stage I-incubation of expiants in the dark for 2 weeks on Murashige Skoog (MS) medium containing 2,4-dichlorophenoxyacetic acid (2,4-D) (2.5 mg/l) and 6-benzylaminopurine (0.25 mg/l) and, (2) stage II-culture in the light on MS medium with abscisic acid (ABA) (2.5 mg/l). The addition of ABA was critical for enhanced production of somatic embryos. Secondary somatic embryos were produced from the primary embryos cultured on MS medium with 2,4-D at 0.2 mg/l. The somatic embryos were converted into normal plantlets when cultured on basal MS medium. Upon transfer to soil, plants grew well and appeared normal with no mortality. The system of somatic embryogenesis described here will facilitate tissue culture, germplasm conservation and gene transfer research of sweetpotato due to its rapidity (6 to 10 weeks), prolific plant production by direct embryogenesis, ease of secondary somatic embryo production and reproducibility.Abbreviations ABA
abscisic acid
- BAP
6-benzylaminopurine, 2,4-D-2,4-dichlorophenoxyacetic acid
- GA3
gibberellic acid
- KIN
kinetin
- MS
medium of Murashige and Skoog (1962)
- NAA
1-naph-thaleneacetic acid
- PIC
picolinic acid
- TDZ
thidiazuron 相似文献
16.
The study was carried out to establish in vitro culture conditions for plant regeneration of tef, Eragrostis tef (Zucc.) Trotter. Mature seeds of two Ethiopian varieties, DZ-01-354 and DZ-01-196, were used to initiate callus cultures
on Murashige and Skoog (MS) medium with different auxins. Four- and 8-week-old calli induced on a medium with 2.0 mg/l 2,4-dichlorophenoxyacetic
acid (2,4-D) were subcultured onto various media to induce somatic embryogenesis. Compact, nodulated, embryogenic callus was
observed after transfer onto MS-callus proliferating (CP) medium. Embryogenic tissue appeared on soft and amorphous callus
and developed into somatic embryos during a subsequent subculture to MS embryo-promoting (EP) media. Various growth regulator
combinations were tested in CP and EP media to obtain a high efficiency of somatic embryo formation. The highest frequency
of calli forming somatic embryos (56.1–68.3%) was observed when CP media with 2.0 or 4.0 mg/l 2,3,5-triiodobenzoic acid were
employed and then cultures were transferred to EP media with 0.5 mg/l 2,4-D and 0.5 mg/l kinetin followed by 0.5 mg/l indole-3-acetic
acid and 0.5 mg/l N6-benzyladenine. Plant development from somatic embryos was obtained on MS medium supplemented with 1.0 mg/l gibberellic acid.
On average, 71.2% of calli displaying somatic embryos converted into plants. Regenerated plants were successfully transferred
to soil. Neither chlorophyll-deficient plants nor morphological variants were found among regenerants. All regenerated plants
were fertile.
Received: 9 May 1997 / Revision received: 25 September 1997 / Accepted: 3 January 1998 相似文献
17.
Summary Somatic embryogenesis and plant regeneration have been achieved in Nothapodytes foetida, which is known for its rich source of anti-cancer and anti-AIDS alkaloids. Callus cultures were initiated from immature
zygotic embryos cultured on Murashige and Skoog's (MS) medium supplemented with 2,4-dichlorophenoxyacetic acid, 6-benzyladenine
(BA), and kinetin. MS medium devoid of plant growth regulators favored the development of globular somatic embryos that differentiated
further into plantlets. Plantlet regeneration efficiency was effectively increased on MS medium supplemented with BA. Over
90% of the in vitro plantlets survived when transferred to the soil. Alkaloids were detected in different stages of somatic embryos, regenerated
plantlets, and different parts of the 2-yr-old regenerated plants. The somatic embryos contains camptothecin (0.011% dry weight.
DW) and 9-methoxycamptothecin (0.0028% DW). Two-yearold field-grown plants obtained from somatic embryos were analyzed and
contained higher levels of camptothecin (0.20% DW) and 9-methoxycamptothecin. (0.097% DW) accumulated in roots, followed by
stem and leaves. Alkaloids were quantified and identified by TLC and HPLC. 相似文献
18.
Helena Mathews C. Schopke R. Carcamo P. Chavarriaga C. Fauquet R. N. Beachy 《Plant cell reports》1993,12(6):328-333
Methods for improving the efficiency of plant recovery from somatic embryos of cassava (Manihot esculenta Crantz) were investigated by optimizing the maturation regime and incorporating a desiccation stage prior to inducing germination. Somatic embryos were induced from young leaf lobes of in vitro grown shoots of cassava on Murashige and Skoog medium with 2,4-dichlorophenoxy acetic acid. After 15 to 20 days of culture on induction medium, the somatic embryos were transferred to a hormone free medium supplemented with activated charcoal. In another 18 days mature somatic embryos became distinctly bipolar and easily separable as individual units and were cultured on half MS medium for further development. Subsequent desiccation of bipolar somatic embryos resulted in 92% germination and 83% complete plant regeneration. The plants were characterized by synchronized development of shoot and root axes. Of the non-desiccated somatic embryos, only 10% germinated and 2% regenerated plants. Starting from leaf lobes, transplantable plantlets were derived from primary somatic embryos within 70 to 80 days.Abbreviations 2,4-D
2,4 dichlorophenoxyacetic acid
- BA
Benzyl aminopurine
- GA
Giberellic acid
- MS
Murashige and Skoog
- NAA
Naphthalene acetic acid 相似文献
19.
M. Muruganantham S. Amutha A. Ganapathi 《In vitro cellular & developmental biology. Plant》2010,46(1):34-40
The regeneration of plants via somatic embryogenesis liquid shake culture of embryogenic calluses was achieved in Vigna mungo (L.) Hepper (blackgram). The production of embryogenic callus was induced by seeding primary leaf explants of V. mungo onto Murashige and Skoog (MS) (Physiol Plant 15:473–497, 1962) medium supplemented (optimally) with 1.5 mg/l 2,4-dichloro-phenoxyacetic acid. The embryogenic callus was then transferred
to liquid MS medium supplemented (optimally) with 0.25 mg/l 2,4-dichloro-phenoxyacetic acid. Globular, heart-shaped, and torpedo-shaped
embryos developed in liquid culture. The optimal carbohydrate source for production of somatic embryos was 3% sucrose (compared
to glucose, fructose, and maltose). l-Glutamine (20 mg/l) stimulated the production of all somatic embryo stages significantly. Torpedo-shaped embryos were transferred
to MS (Physiol Plant 15:473–497, 1962) liquid medium containing 0.5 mg/l abscisic acid to induce the maturation of cotyledonary-stage embryos. Cotyledonary-stage
embryos were transferred to 1/2-MS semi-solid basal medium for embryo conversion. Approximately 1–1.5% of the embryos developed
into plants. 相似文献
20.
L. O. das Neves S. R. L. Duque J. S. de Almeida P. S. Fevereiro 《Plant cell reports》1999,18(5):398-405
Medicago truncatula ssp Narbonensis and four genotypes of M. truncatula Gaertn cv. Jemalong were tested for their somatic embryogenesis potential using a two-step protocol. In the first step, embryogenic
callus was induced in folioles isolated from shoots grown in vitro and cultured on Murashige and Skoog (MS) medium supplemented
with 2,4-dichlorophenoxyacetic acid and zeatin. In the second step, somatic embryos were allowed to develop from the induced
callus in MS growth-regulator-free medium. Individual somatic embryos were then isolated and transferred again to growth regulator
free medium where they formed secondary somatic embryos in repetitive cycles. Conversion of somatic embryos into plantlets
was achieved by isolating late-torpedo-phase somatic embryos with distinct cotyledons and reculturing them onto MS growth
regulator free medium. The system of repetitive somatic embryogenesis in M. truncatula described here represents a permanent source of embryogenic material that can be used for the genetic modification of this
species.
Received: 7 August 1997 / Revision received: 22 December 1997 / Accepted: 20 January 1998 相似文献