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1.
Reseda pentagyna is the only endemic species among the seven species of the genera Reseda found in Saudi Arabia. Probably no information is available on regeneration by conventional method of regeneration through seeds or cuttings. Therefore, alternative method of tissue culture was attempted to regenerate and multiply the plant. High shoot regeneration (14.44 shoots/explant) was obtained after four weeks, when shoot cuttings cultured on MS containing BA at 1.0 µM. Other cytokinins e.g., Kn, 2iP and TDZ found to be less effective in bud induction and shoot multiplication. Individual shoots were rooted on MS medium supplemented with various auxins at 0.5–5.0 µM concentrations. The IBA (1.5 µM) supplemented MS media induced maximum (83.3%) rooting. The plantlets were acclimatized and hardened under greenhouse conditions in plastic pots containing soil and farm yard manure with 95.0% success. The protocol developed would help to multiply the plant as well as conserve them in natural habitat. This can also be utilized to obtain active constituents for pharmaceutics and genetic manipulations.  相似文献   
2.
Seed explants of A. stenosperma were cultured on MS medium supplemented with 6-benzylaminopurine with the aim of rescuing nonviable accessions stored in seed bank conditions. The regeneration potential of leaf explants from in vitro plants derived from embryonic axes was studied by using whole leaflets and leaflet segments. Explants were cultured on Murashige and Skoog (MS) medium supplemented with different concentrations of 6-benzylaminopurine and naphthalene acetic acid. Indirect organogenesis was observed in response to 6-benzylaminopurine, either alone or in association with naphthalene acetic acid, in both explant types. Media supplemented with naphthalene acetic acid as the sole growth regulator induced rhizogenesis in whole leaflets and leaflet segments, with subsequent shoot production directly from the roots.  相似文献   
3.
大野芋种子形成丛生芽的微繁殖   总被引:3,自引:0,他引:3  
大野芋(Colocasiagigantea)的成熟种子(褐色)和未成熟的种子(淡黄色)在1/2MS培养基上均能萌发,种子萌发率最高达50%,种子没有休眠期。在室温下,种子在1/4MS 1%蔗糖培养基上,寿命约可达1年。种子在MS BA2mg·L-1 IAA0.25mg·L-1的培养基上,产生丛生芽。增值率1∶4/60d。生根培养基为MS NAA0.3mg·L-1,生根率达95%以上。通过诱导大野芋种子产生丛生芽,建成了快繁无性系,并成功地实现了种子的离体保存。本研究工作的完成,对于芋头的这一野生近缘种的保存和利用、芋头品种的改良,均具有较大意义。  相似文献   
4.
Summary The present work deals with the in vitro methods for rapid propagation, and morphogenetic potential of the rare and endangered bulb species Leucojum aestivum L., Amaryllidaceae, and Lilium rhodopaeum Delip., Liliaceae. The morphogenetic potential of different plant organs (bulb, stem, leaves and ovaries) was studied. Leaves of Leucojum aestivum L. and basal parts of the bulb in Lilium rhodopaeum Delip. possess the highest regeneration activity. Murashige and Skoog (MS) medium + 1 mg/l 6-benzylaminopurine (BAP) + 1 mg/l kinetin and Linsmaier and Skoog (LS) medium + 0.5 mg/l 1-naphthaleneacetic acid (NAA) + 0.1 mg/l kinetin were favourable for direct organogenisis from these explants. A stimulating effect of alow gamma-irradiation dose (5 Gy) upon the quantity and growth intensity of the bulbs formed by the explants in in vitro conditions is observed.  相似文献   
5.
Renealmia mexicana (Klotzsch ex. Petersen) is a tropical plant found in southern México with an ornamental value and a potential source of curcuminoids. Its distribution in Chiapas has decreased because of deforestation and low propagation and germination rate, so a protocol for in vitro propagation was developed. An orthogonal experimental design of L9 (34) in triplicate was used to investigate the effect of 6-benzyl adenine (BA), indole butyric acid (IBA), silver nitrate (AgNO3), and sucrose on shoot, root, and leaf development of plantlets grown in vitro. Plantlets with well-developed shoots and roots were transferred to pots containing a mixture of peat moss and agrolite for hardening before transfer to soil. The Murashige and Skoog (Physiol. Plant. 15:473–497, 1962) mineral medium (MS) supplemented with 4.4 μM BA, 2.5 μM IBA, 11.7 μM AgNO3y and 5.5% (w/v) sucrose gave most shoots, 8.9 μM BA, 2.5 μM IBA, 17.7 μM AgNO3 and 5.5% (w/v) sucrose most roots, and 8.9 μM BA, 4.9 μM IBA, 11.7 μM AgNO3 and 3.0% (w/v) sucrose most leaves, although other combinations were statistically equivalent in each case. Sucrose was the factor that most explained the variation in the promotion of shoots, roots, and leaves. The protocol developed resulted in up to 100% survival when plantlets were transferred to soil using AgNO3, confirming that hardening of plantlets in vitro using hormonal stimulation was a suitable strategy to improve acclimatization.  相似文献   
6.
A rapid and efficient method for the large-scale propagation of a highly valuable medicinal plant, Andrographis paniculata Nees, through in vitro culture of nodal explants obtained from 15-d-old aseptic seedling has been developed. High frequency direct shoot proliferation was induced in nodal explants cultured on Murashige and Skoog’s medium supplemented with 6-benzylaminopurine (BAP). Amongst the various cytokinins tested (BAP, kinetin, thidiazuron and 2-isopentyl adenine), BAP proved to be the most effective. The shoot forming capacity of the nodal explants was influenced by the BAP concentration (1–12.5 μM), and the optimal response was observed at 10 μM BAP, which induced an average of 34 shoots in 94% of the cultures within 4 wk. Significant differences were recorded in terms of average number of shoots per explant (8.6–34.1) among the different concentrations of BAP investigated. Concentrations of all cytokinins tested reach a level that can be considered above the optimum level, as marked by a reduced frequency of shoot proliferation. The multiple shoots obtained on various concentrations of BAP failed to elongate even after transfer to hormone-free MS medium. Elongation of the induced shoots was achieved on MS basal medium supplemented with 1.0 μM GA3 within 2 wk. A proliferating shoot culture was established by repeatedly subculturing the original nodal explants on shoot multiplication medium after each harvest of the newly formed shoots. The explants retained their morphogenic potential even after three harvests. Therefore, in 90 d, about 60–70 shoots were obtained from a single nodal explant and the nodal explants from primary shoots further regenerated equivalent number of shoots, depicting their high frequency regeneration potential in A. paniculata. Rooting was best induced in 94% of shoots cultured on MS medium supplemented with 2.5 μM indole-3-butyric acid (IBA), within a wk. The plantlets were successfully transferred to soil after hardening with a 92% survival rate. The system is rapid: the initiation of shoot buds to the transplanting of regenerants to soil is completed in 8–9 wk.  相似文献   
7.
 The effect of different genotypes of the ectomycorrhizal fungus Hebeloma cylindrosporum on in vitro rooting of micropropagated cuttings of Prunus avium and P. cerasus was studied in an attempt to determine whether ectomycorrhizal fungi could enhance in vitro adventitious root formation in plants which form arbuscular endomycorrhizas. The rooting percentage of P. avium cuttings was approximately 16% in the absence of hormonal treatment; it increased up to 30% in the presence of 5.7 μM IAA which was the most favourable auxin concentration. The rooting percentage of cuttings cultivated in the absence of IAA was enhanced by all the studied strains of H. cylindrosporum. It ranged from 50 to 60% with the IAA-overproducing mutant D 111 or the wild-type dikaryon D1, to 100% in the presence of the mutants 331 or D 117. The cuttings of P. cerasus showed a higher rooting ability than those of P. avium since approximately 40% of them were able to root in the absence of hormonal treatment. Except for the mutant D117, their rooting percentage was not significantly improved by H. cylindrosporum. Fungal inoculation also affected the survival of cuttings at acclimatization: 50% of the uninoculated P. avium cuttings survived whereas the survival percentage of inoculated cuttings ranged from 30 to 100% depending on the fungal genotype. With P. cerasus, the percentage of survival of uninoculated cuttings ranged from 85 to 100% and fungi either did not significantly improve it or lowered it. At acclimatization fungal hyphae could be observed in close contact with adventitious roots, but they did not establish mycorrhizal association. The shoot height of P. avium plantlets obtained from inoculated cuttings was not significantly different from that of plantlets originating from uninoculated ones. By contrast, fungal inoculation generally depressed the growth of acclimatized P. cerasus plantlets. The possibility of using ectomycorrhizal fungi as a tool to enhance rooting of micropropagated cuttings of plants which do not form ectomycorrhizas is discussed. Received: 25 November 1996 / Accepted: 2 June 1997  相似文献   
8.
Induction of multiple shoots in cotton (Gossypium hirsutum L. cv. Anjali-LRK 516) has been achieved with cotyledonary nodes devoid of cotyledons and apical meristems. Explants from 35-day-old seedlings yielded the maximum number of shoots (4.7 shoots/explant) using Murashige and Skoog (MS) basal medium supplemented with 6-benzylaminopurine and kinetin (2.5 mg/1 each). Explants from 35-day-old seedlings raised in glass bottles produced a higher number of multiple shoots (8.3 shoots/explant) than those grown in glass tubes and cultured on the same shoot induction medium. Elongation of multiple shoots was obtained on liquid or agar MS basal medium without phytohormones. In vitro shoots were rooted on half-strength agar-solidified MS basal medium or with 0.05 or 0.1 mg/1 naphthaleneacetic acid. Hardening and survival of tissue culture plantlets was 95% under greenhouse conditions.Abbreviations BAP 6-Benzylaminopurine - GA3 Gibberellic acid - MS Murashige and Skoog medium - NAA -Napthaleneacetic acid  相似文献   
9.
Micropropagation of mature Chinese tallow tree (Sapium sebiferum Roxb.)   总被引:1,自引:0,他引:1  
An in vitro propagation technique based on axillary bud proliferation has been developed for matureSapium sebiferum trees. Nodal segments cultured on Murashige and Skoog (MS) medium supplemented with benzyl adenine (1–10 m and -naphthaleneacetic acid (0–0.5 m showed axillary bud proliferation. Shoots proliferated in vitro were multiplied on Murashige and Skoog medium containing 2.5 m benzyl adenine and 0.25 m -naphthaleneacetic acid. Seasonal changes affected the shoot proliferation potential of the initial explant. Shoots were rooted on a half-strength, growth-regulator-free, agar-gelled, MS medium after a 48-h treatment on half-strength MS liquid medium with 10 m indole-3-butyric acid. Rooted plantlets were potted and acclimatized in a growth chamber and then moved to the greenhouse. Four-month-old plants were transplanted to the field.Abbreviations BA Benzyl adenine - IBA Indole-3-butyric acid - 2-ip N6-(-dimethylallylamino)purine - MS Murashige and Skoog (1962) medium - NAA -Naphthaleneacetic acid  相似文献   
10.
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