首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 31 毫秒
1.
Thidiazuron (TDZ) induced somatic embryogenesis from immature zygotic embryos in Cinnamomum pauciflorum Nees while 2,4-dichlorophenoxyacetic acid (2,4-D), 6-benzylaminopurine (BA) or picloram only induced callus and/or adventitious buds. The highest induction frequency for somatic embryogenesis was achieved with MS medium (Murashige and Skoog in Physiol Plant 15:473–497 1962) supplemented with 2.5 μM TDZ using torpedo-shaped embryos (3–5 mm in length) as explants. In addition, induction medium was supplemented with 0.8 g l−1 casein, 0.4 g l−1 glutamine, and 10 g l−1 sucrose. Somatic embryos (SEs) initiated from root tips or hypocotyls without callus formation. SEs were maintained and multiplied via secondary somatic embryogenesis. Embryo maintenance medium was similar to induction medium except that TDZ was reduced to 0.5 μM. Secondary embryogenesis was enhanced by supplementation of 5 g l−1 activated charcoal in the culture. The best medium for embryo maturation was MS medium containing 30 g l−1 sucrose and 5 g l−1 Phytagel without plant growth regulators. A typical mature SE consisted of two large cotyledons and a short embryo proper. Approximately 82% of selected mature SEs were able to germinate and 63% could convert into plantlets on germination medium that was composed of half strength MS medium salts, 10 g l−1 sucrose, 3 g l−1 Phytagel, and 5 g l−1 activated charcoal.  相似文献   

2.
Leaves of fine Populus tomentosa genotype TC152 were used as explants to establish cell suspension lines. The effects of plant growth regulators on callus induction and establishment of cell suspension lines were studied. The callus induction rate was the highest on a MS solid medium supplemented with 1.0 mg·L^-1 2,4-D. A cell suspension line could be obtained by inoculating calli which were not subcultured into a MS liquid medium supplemented with 1.5 mg·L^-1 2,4-D. The best subculture medium was MS ＋ 0.8 mg＇L-1 2,4-D ＋ 30 g·L^-1 sucrose with a subculture cycle of seven days.  相似文献   

3.
Cottonhead windhairdaisy (Saussurea laniceps Hand.-Mazz.) is one of the most famous and important medicinal herbs in China. Illegal collection from wild populations is increasingly threatening the present environment of S. laniceps. Establishment of an efficient method for micropropagation is the best way to change its endangered situation. When mature seeds of S. laniceps were cultured on hormone-free MS medium, plantlets were formed from germinated seeds in 7–10 d. Then 0.5 cm × 0.5 cm leaf explants were transplanted to MS medium supplemented with 1-naphthalene-acetic acid (NAA)/2,4-D and benzyladenine (BA)/KT and callus was achieved 10 d after transfer. Shoot bud regeneration occurred from callus cultured on MS medium supplemented with different growth regulators 20 d after culturing. The regeneration percentages varied with the different components of plant growth regulators. The percent regeneration from callus pretreated at low temperature of 5°C increased significantly compared with those incubated at 23/20°C directly. Optimal regeneration was observed with explants on media supplemented with 1.5 mg•L–1 BA plus 0.2 mg•L-1 NAA. In the presence of 0.2 mg•L–1 NAA in half-strength MS, 78% of the shoots formed roots. Plantlets from explants showed 63% survival after acclimatization.  相似文献   

4.
Cerasus humilis is a species of small, perennial, drought-resistant and multipurpose deciduous shrub grown in arid and semi-arid conditions in northern China. In this study, an efficient protocol for the rapid micropropagation of C. humilis has been standardized using stem and/or leaf explants. Direct multiple shoot induction was observed when the stem explants were cultured on Murashige and Skoog (MS) medium supplemented with different plant growth regulators. The highest shoot induction was obtained when stem explants from adult trees were cultured on MS medium supplemented with 2.0 mg L?1 6-benzyladenine (6-BA) and 0.9 mg L?1 α-naphthaleneacetic acid (NAA). The leaf and stem explants cultured on MS medium with 1.0 mg L?1 6-BA and 0.6 mg L?1 NAA, and 0.5 mg L?1 6-BA and 0.8 mg L?1 NAA, respectively, produced the highest induction frequency of callus. Maximum proliferation of callus was observed on MS medium containing a combination of 0.5 mg L?1 6-BA with 0.6 mg L?1 2,4-dichlorophenoxyacetic acid (2,4-d). Optimal shoots differentiated from callus were obtained on MS medium supplemented with 5.0mg L?1 6-BA and 0.9 mg L?1 NAA. In vitro rooting was achieved on half-strength (1/2) MS medium containing 0.5 mg L?1 NAA. Rooted plantlets were hardened under control conditions and successfully acclimatized under field conditions.  相似文献   

5.
We attempted to develop a method for the regeneration of plantlets from mature seeds of medically important Magnolia obovata via the induction of somatic embryogenesis in vitro. We initially cultured halves of mature seeds on either Murashige and Skoog (MS) medium or B5 medium that contained 0, 1, 5 or 10 μM gibberellic acid (GA3) for 1 month and then transferred the half-seeds to half-strength MS basal medium or B5 basal medium for further culture in the absence of GA3. Proembryogenic masses (PEMs) were observed 1 month after the transfer of the halved mature seeds to the medium without GA3. The frequency of formation of PEMs was higher (28%) after initial culture in MS basal medium plus 1 μM GA3 than in other tested media (0 or 4%). Somatic embryos that had been developed from PEMs were cultured on half-strength MS basal medium or B5 basal medium for completion of maturation and then transferred to fresh aliquots of the same medium for initiation of germination. The frequency of germination, with the formation of normal primary leaves and roots, was above 80%. We transferred the somatic embryo-derived plantlets to soil for acclimatization and the plantlets continued to thrive.  相似文献   

6.
We developed a shoot multiplication protocol for Syringa reticulata Blume var. mandshurica Hara from in vitro cultured seedlings that derived from in vitro germinated seeds. The shoots could be induced on Murashige and Skoog (MS) medium with proper plant growth regulator combinations of 6-benzylaminopurine (BA) and indole-3-butyric acid (IBA). The better medium for shoot multiplication and growth was MS + 5 mg L?1 BA + 0.5 mg L?1 IBA + 20 g L?1 sucrose + 7 g L?1 agar, and the corresponding shoot induction rate was 75 %. The plantlets grew well after rooting on 1/2MS medium (macro-elements of MS medium are at half-strength) supplemented with 1 mg L?1 IBA, and the survival percentage was >80 % at 16 weeks after transplanting.  相似文献   

7.
Nitraria sibirica Pall. is a shrub that grows in saline-alkali soil and has traditional medicinal value and potential commercial value. The objectives of this study include induction and multiplication of callus, establishment of a suspension cell line, and isolation of protoplasts from cell suspensions. Murashige and Skoog (MS) medium was used for callus induction from mature seeds of N. sibirica. Seed-derived calluses were further multiplied on MS medium augmented with 0.5 mg L?1 6-benzylaminopurine (6-BA) and 1.0 mg L?1 2,4-dichlorophenoxy (2,4-D) acetic acid. Suspension cultures of N. sibirica were initiated by transferring friable calli to the same liquid multiplication medium. Characterization of the suspension culture was assessed based on fresh mass, dry mass, cell viability and pH value of the culture. A typical growth curve was observed after inoculating 1.5 g of callus in 40 mL liquid medium, including a lag phase, an exponential growth phase, a stationary phase, and a negative acceleration phase. The effect of factors such as pre-plasmolysis, enzyme combination, enzymolysis time and mannitol concentration, on the isolation of cell-derived protoplasts were evaluated to determine the usefulness of suspension cultures. The maximum yield (9.79 × 106 cells/g) and highest viability (79.97%) of protoplast were reached when approximately 1 g of cell suspension (cultured for 6 days) was inoculated for 12 h in cell and protoplast washing solution made of 0.8 mol L?1 mannitol mixture solution, cellulose onozuka R-10 2% (w/v), hemicellulose 0.2%, macerozyme R-10 1%, and pectolyase Y-23 0.5%. Protoplast yield was significantly influenced by pre-plasmolysis and cellulose onozuka R-10 (P < 0.05).  相似文献   

8.
We studied morphological, biochemical and physiological leaf acclimation to incident Photon-Photosynthetic-Flux-Density (PPFD) in Quercus ilex (holm oak) and Quercus suber (cork oak) at Mediterranean evergreen oak woodlands of southern Portugal. Specific leaf area (SLA) decreased exponentially with increasing PPFD in both species. Q. ilex had lower SLA values than Q. suber. Leaf nitrogen, cellulose and lignin concentration (leaf area-based) scaled positively with PPFD. Maximum rate of carboxylation (Vcmax), capacity for maximum photosynthetic electron transport (Jmax), rate of triose-P utilization (VTPU) and the rate of nonphotorespiratory light respiration (Rd) were also positively correlated with PPFD in both Quercus species, when expressed in leaf area but not on leaf mass basis. Q suber showed to have higher photosynthetic potential (Vcmax, Jmaxm and VTPUm) and a higher nitrogen efficient nitrogen use than Q.ilex. Leaf chlorophyll concentration increased with decreasing PPFD, improving apparent quantum use efficiency (Φ) in both Quercus species. We concluded that, in Q.ilex and Q.suber, leaf structural plasticity is a stronger determinant for leaf acclimation to PPFD than biochemical and physiological plasticity.  相似文献   

9.
  相似文献   

10.
Bambusa nutans Wall., is an evergreen, perennial, and multipurpose bamboo having strong culms, which are largely used for construction, scaffolding, craft purposes, pulp, and paper industry. Multiple shoots from nodal segments (3–4 cm) of young branches of mature culms were established in Murashige and Skoog (1962) (MS) medium supplemented with various concentrations of 6-benzylaminopurine (BAP) (1.0–6.0 mg l−1) or in combination with α-naphthaleneacetic acid (NAA) (0.5–1.0 mg l−1) or kinetin (Kn) (1.0–2.0 mg l−1). February–March and December were found to be the best seasons for culture establishments. Maximum shoots were achieved on MS medium fortified with BAP (2.0 mg l−1). Embryogenic callus (slightly greenish compact, globular, and slow growing) was initiated from the base of severed sprouted buds in 2–3 subsequent subcultures on MS medium supplemented with 2,4-dichlorophenoxy acetic acid (2,4-D) (5.0 mg l−1) under dark incubations. Maturation and germination of well-organized somatic embryos was achieved on MS medium containing BAP and 2,4-D (1.0 mg l−1 each) with 20.0 mg l−1 ascorbic acid. Full-strength MS medium supplemented with 2% glucose favored further development of proliferated somatic embryos into plantlets. Genetic variations of field-established B. nutans plants regenerated through tissue cultures were assessed by amplified fragment length polymorphism (AFLP) analysis using 6 primer combinations. Four hundred and seven scorable fragments were amplified, of which 402 (98.8%) have recorded conservation at various morphogenetic stages leading to plantlets regeneration, therefore, revealed a high level of genetic stability.  相似文献   

11.
Eucalyptus is very recalcitrant to in vitro culture. In this research, an efficient shoot organogenesis system was developed using 60-day-old plants of Eucalyptus globulus grown in vitro and non-aerated liquid medium to improve shoot proliferation. Cultures were initiated with hypocotyls and leaf segments from plantlets cultivated on semisolid ½ MS modified medium supplemented with 4.44 µM 6-Benzyladenine (BA) and 16.1 µM 1-Naphthaleneacetic acid (NAA). Calli were transferred to shoot induction medium, with either 0.5 or 2.7 µM NAA. Shoot multiplication was carried out on 4.44 µM BA + 0.5 µM NAA medium, and semisolid and non-aerated liquid systems were compared for improving shoot proliferation. Rooting of adventitious shoots was evaluated on medium containing NAA or Indole-3-butyric acid -IBA (5 and 16 µM). Callogenesis was obtained from both types of explants, although shoot formation was only obtained from leaf-derived calli. Shoot proliferation on 4.44 µM BA + 0.5 µM NAA resulted in the most shoots/callus. Non-aerated liquid medium was more efficient in promoting shoot multiplication (53.5 shoots/callus) than was semisolid medium (28.5 shoots/callus). Levels of phenolic compounds were significantly reduced in the shoots cultivated in liquid medium. Efficient rooting (76%) was obtained using 16 µM IBA.  相似文献   

12.
Tea tree oil is extracted from the leaves and twigs of Melaleuca alternifolia (Maiden & Betche) Cheel, and it is widely used in medicines, food preservatives, cosmetics and health care products. Traditional propagation of M. alternifolia from seeds does not necessarily transfer the desired characteristics from their mother trees, the seedlings are not uniform, and the multiplication rate from cuttings is relatively low. For these reasons, it is necessary to develop tissue culture techniques for this species. This study showed that an efficient explant initiation medium for M. alternifolia was MS 1/2 + BA 0.6 mg L?1 + NAA 0.1 mg L?1 + sucrose 30 g L?1, which yielded a 75.9 % initiation rate. An efficient multiplication medium was MS + BA 0.3 mg L?1 + NAA 0.15 mg L?1 + sucrose 30 g L?1, which yielded a 4.3 multiplication rate and 3.2 cm shoot length. The rooting medium was MS 1/2 + IBA 0.1–0.25 mg L?1 + sucrose 15 g L?1, which yielded a 100 % rooting rate, 2.94–3.32 roots per individual and 1.36–1.44 cm root length. Local red-core soil was suitable as a transplant medium, and yielded 98 % survival. This study improved the tissue culture technique for mass-propagation of M. alternifolia, enabling the production of high quality plants for market.  相似文献   

13.
With embryogenic callus of Larix olgensisis, we investigated the effects of inositol, glutamine, casein hydrolysate, carbohydrate, abscisic acid and silver nitrate concentration on the maturation of the somatic embryo. Three dominant factors emerged, and we developed a response surface model based on the Box–Behnken design. We defined the optimal conditions for the maturation of somatic embryos. The contents of abscisic acid, silver nitrate, sucrose and casein hydrolysis significantly affected the amount of maturing embryos, but inositol, maltose and glutamine had no effect. By establishing a response surface model with multiple factors, we predicted that the optimal number of L. olgensis somatic embryos was 204?±?4 g?1 on basal medium, containing 18.28 mg L?1 abscisic acid, 5.46 mg L?1 silver nitrate and 82.67 g L?1 sucrose. In the verification experiments, the addition of 20 mg L?1 abscisic acid, 5 mg L?1 silver nitrate and 80 g L?1 sucrose to BM yielded an average of 202.06 somatic embryos per gram. These results should guide large-scale breeding of L. olgensis.  相似文献   

14.
A micropropagation method for Jaal (Salvadora persica)—a tree of arid horticulture and forestry has been developed. Nodal segments of fresh shoot sprouts originated from axillary buds obtained from a plant around 35–40 years old lopped plant were used as explants for establishment of in vitro cultures. Surface-sterilized explants produced optimum number of shoots through activation of axillary buds on Murashige and Skoog’s (MS) medium containing 8.88 μM BA (6-benzyladenine) + additives (25 mgl−1 each of adenine sulphate, arginine, citric acid, 50 mgl−1 ascorbic acid). The shoot multiplication was influenced by the successive transfer of the mother explants for 4–5 passages. The maximum number (23.1 ± 0.73 shoots per explant) of shoots were regenerated on MS supplemented with 1.11 μM BA + 1.16 μM Kn (Kinetin) + 0.54 μM NAA (α-naphthalene acetic acid). About 90% shoots pulse-treated with a combination of 2460.27 μM Indole-3-butyric acid (IBA) + 494.56 μM NOA (2-naphthoxy acetic acid) were rooted ex vitro on soilrite within 15–18 days. Over 80% cloned plantlets were hardened successfully in a green house and transferred to polybag/pots.  相似文献   

15.
Since the generation of full-sib artificial triploid families, rapid clone establishment and genetic improvements have been needed. Here, we report an in vitro method of direct shoot regeneration of a triploid hybrid poplar [(Populus simonii × P. nigra ‘Italica’) × (P. × ‘popularis’)]. Using different randomized block designs, we selected one triploid to evaluate the explant type, optimal concentrations of plant growth regulators and agar, and culture time under light or dark conditions over 60 days. The highest rate of shoot induction, 80.0%, was obtained using Murashige and Skoog (MS) medium supplemented with 0.2 mg/L benzyladenine, 0.04 mg/L naphthaleneacetic acid (NAA), and 5.5 g/L agar for the first 30 days in the dark, then 3 g/L agar for the next 30 days in light. This last medium yielded the best rate of shoot induction (6.32 shoots/explant). These three media were also used to evaluate the influence of the genotypes of the parents and hybrid triploids on regeneration. Two parents and three of the four full-sib triploids were regenerated successfully; different genotypes and explant types significantly affected the rate of shoot induction and average number of shoots. Leaves but not petioles were a suitable explant. One genotype produced the highest rate of shoot induction of 96.67%. Half-strength MS medium supplemented with 0.2 mg/L indole butyric acid and 0.04 mg/L NAA was the most effective for rooting; rooting rate was 96.67%, survival rate of transplants was 73.33%, and rooting frequency surpassed 85% for each genotype. Overall, this in vitro regeneration system will be useful for the propagation and genetic modification of triploid poplars.  相似文献   

16.
A reliable in vitro regeneration procedure for Populus tomentosa is a prerequisite for its trait improvement through genetic transformation. We established a systematic protocol for indirect regeneration of P. tomentosa using in vitro petioles of Chinese poplar cultivar ‘fasta-3’. A high frequency of callus induction (>97 %) was obtained from isolated petioles cultured on the modified 1/2MS basal medium supplemented with 0.5 mg/L ZT and 1.0 mg/L NAA, and the tested calli were subsequently plated on 1/2MS basal medium supplemented with 0.25 mg/L BA, 0.25 mg/L ZT, 0.25 mg/L NAA, 0.01 mg/L TDZ, and 0.5 mg/L KT for efficient regeneration of shoots after being cultured for 6 weeks. The regenerated shoots were vigorously rooted on the tested media supplemented with 1.0 mg/L IBA and 0.5 mg/L NAA. These results can facilitate genetic transformation of P. tomentosa for trait improvements in future.  相似文献   

17.
Antifeedant activities of the isolated chemical compounds from Ajuga nipponensis, were studied against adult of striped leaf beetles. The methanol, petroleum ether, ethyl acetate and n-butanol extracts at 1.0 mg/ml, were used in this study. All four extracts exhibited more than 65 antifeedant index at 24 h and ethyl acetate extract showed significant activity against striped leaf beetles with 83.12 antifeedant index. Six compounds and one fraction were isolated by chromatography and their structures were identified by NMR, MS and FTIR spectra. At 2.0 mg/ml for 24 h the three compounds 20-hydroxyecdysone, acacetin and apigenin showed considerable activities with antifeedant indexes 59.29, 51.22 and 61.55, respectively. In contrast to this the antifeedant indexes of acacetin and apigenin, were sharply reduced as the time extended and that of 20-hydroxyecdysone remained unchanged. In addition, the synergistic effects of two mixtures of secondary metabolites, were studied and no sharp difference was observed.  相似文献   

18.
Dimorphandra jorgei MF Silva (Caesalpinaceae) and Swartzia macrostachya Benth. var. riedelii Cowan (Fabaceae) are tree species from the southern Bahian Atlantic Forest, identified for the restoration of degraded areas. The objective of this research is to study their seed germination and seedling growth to develop simple methods for seedling production in small scale nurseries. Because the species have distinct dormancy and germination characteristics, the seeds were submitted to different treatments. D. jorgei seeds were immersed in hot water, scarified and stored for 12 weeks in the laboratory environment (25°C). S. macrostachya seeds were submitted to different combinations of drying and storage in the laboratory environment or refrigerator (4°C). Seedlings were submitted to two light treatments for 3 months: partial shade (52% of full sun) and full shade (12% of full sun). In D. jorgei, the highest germination occurred for scarified seeds (87%) and for seeds stored for 12 weeks and then scarified (69%). In S. macrostachya the undried control seeds had the highest germination, followed by that of the refrigeration storage treatment, without predrying (99% and 97%, respectively). The average values for the growth parameters were greater in full shade for D. jorgei, while S. macrostachya seedlings showed greater growth rates in partial shade. Two months growth is recommended before D. jorgei seedlings are of the sufficient size and leaf number for field planting. On the other hand, a period of 4 months is recommended for S. macrostachya, due to its relatively slow growth.  相似文献   

19.
Red flour beetle Tribolium castaneum (Herbst) and rice weevil Sitophilus oryzae (L.) are considered to be the major insect pests in storage. Essential oils from aromatic plants are recognized as proper alternatives to fumigants. Thymus persicus (Ronniger ex Rech. f.) is one of these plants that have medicinal properties and is indigenous to Iran. The essential oil was obtained from aerial parts of the plant and analyzed by GC and GC–MS. Carvacrol (44.69%) and thymol (11.05%) were the major constituents of the oil extracted. In this experiment, fumigant toxicity of the essential oil was studied against T. castaneum, S. oryzae at 27 ± 1°C and 60 ± 5% RH in dark condition. The adult insects were exposed to the concentrations of 51.9, 111.1, 207.4 and 370.4 μl/l air to estimate median lethal time (LT50) values. The fumigant toxicity was increased in response to increased essential oil concentrations. The LT50 values at the lowest and the highest concentrations tested were ranged from 28.09 to 13.47 h for T. castaneum, and 3.86 to 2.30 h for S. oryzae. It was found that S. oryzae adults were much more susceptible to the oil than T. castaneum. After 24 h of exposure, the LC50 values (95% fiducial limit) for T. castaneum and S. oryzae were estimated to be 236.9 (186.27–292.81) and 3.34 (2.62–4.28) μl/l air, respectively. These results suggest that T. persicus essential oil merits further study as potential fumigant for the management of these stored-product insects.  相似文献   

20.
The ethanol extracts obtained from both leaf and seed in the Thorn apple (Datura stramonium L.) (Solanaceae) were investigated for acaricidal, repellent and oviposition deterrent properties against adult two-spotted spider mites (Tetranychus urticae Koch) (Acari: Tetranychidae) under laboratory conditions. Leaf and seed extracts, which were applied in 167,250 and 145,750 mg/l concentrations, respectively (using a Petri leaf disc-spray tower method), caused 98 and 25% mortality among spider mite adults after 48 h. The simple logistic regression analysis showed that the independent variable, an increase in the dose of leaf extract was associated with a significant increase in the death rate of T. urticae females, but an increase in the dosage of seed extracts did not have a significant effect. Using probit analysis and estimating the parameters with a confidence limit of 95%, we determined the LC50 values of leaf extract to be 70,593 mg/l. According to Pearson’s χ2 test, mites showed the strongest run off to bean leaf surfaces sprayed with both leaf and seed extracts (in sub-lethal doses: <7,500 mg/l and <25,000 mg/l, respectively) and moved towards surfaces that had not been sprayed with extracts. Furthermore, repeated measures ANOVA indicated a significant difference between the number of eggs laid on unsprayed bean leaves compared to bean leaves that were sprayed with leaf and seed extracts at sub-lethal doses, 2,500 and 25,000 mg/l concentrations, respectively. These results suggest that D. stramonium extracts could be used to manage the two-spotted spider mite.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号