北美枫香的离体培养和植株再生

1植物名称北美枫香(Liquidambar styraciflua L.). 2材料类别幼嫩枝条. 3培养条件(1)腋芽诱导培养基:MS 6-BA 0.2mg·L-1(单位下同);(2)不定芽增殖培养基:MS 6-BA 0.2,0.5,1.0,2.0 NAA 0.2;(3)壮苗培养基:MS 6-BA 0.2 NAA 0.02;(4)生根培养基:1/2MS IBA 0.2 NAA 0.2.以上培养基pH为5.7～5.8,加入3%蔗糖和0.48%琼脂.培养温度为25℃,光照时间为12 h·d-1,光照度为2 000 1x.     

In vitro propagation of mature Liquidambar styraciflua

Mature specimens of liquidambar styraciflua were propagated in vitro. Components of the nutrient medium and culture conditions were first determined for one-year-old seedling material. Mature material responded similarly to seedling material in culture, but alterations in frequency of early transfers and components of the medium were required. Explants responded best to Woody Plant Medium of Lloyd and McCown supplemented with 0.2 mg l^-1 BA and 0.05 mg l^-1 NAA. Root formation occurred on shoots placed on media containing 0.5–1.0 mg l^-1 IBA. Growth in culture and percentage of rooting of mature explants were markedly affected by the individual selection, with rooting percentages varying from 33–100% among selections.     

In vitro adventitious shoot regeneration from leaves of Prunus spp.

A high level of adventitious shoot regeneration was obtained from proliferating shoots in vitro for a range of Prunus spp. There was a significant variability in clone response to a range of adventitious shoot regeneration treatments. Treatment of apricot clone H.152 with Quoirin macroelements (C.R. Rech., Stu. Cult. Fruit. Maraîchères Gemblaux (1977) 93–117), and both apricot clone H.146 and hybrid plum clone P.1869 with half-strength Murashige and Skoog medium, consistently induced regeneration. Thidiazuron (TDZ) alone, or in combination with naptthaleneacetic acid (NAA), was most effective in stimulating adventitious shoot production, the optimum concentration being clone-dependent. Addition of silver nitrate (AgNO₃) to regeneration media enhanced regeneration by 10–40% and reduced the variability between experiments. Regeneration with AgNO₃ was obtained also for three other plum clones belonging to the P. marianna, P. domestica and P. insititia species.     

In vitro adventitious shoot formation from leaf cultures of Clerodendrum inerme (L) Gaertn.

In vitro adventitious shoots (about 28) of Clerodendrum inerme were regenerated from leaf segments on MS medium containing BA (4 mg/L). These shoots developed directly from the leaf explants without callusing after 5 weeks. Leaf explant when cultured in MS medium containing BA (2 mg/L) and NAA (0.5 mg/L) developed compact callus that became nodular and regenerated shoots (about 50) after 5 weeks. The in vitro developed shoots were rooted in MS medium supplemented with IAA (2 mg/L). The hardened plantlets were successfully established in the field with 90% survival.     

In vitro adventitious shoot production inPaulownia

In vitro adventitious shoot formation was examined in petioles and laminae ofPaulownia elongata, P. fortunei, andP. Henan 1. Fully expanded, dark green, thick, older leaves were healthier and exhibited greater callus and shoot production than did young leaves. The ten clones used varied greatly in adventitious shoot formation. When single explants from the center of each lamina were cultured,P. Henan 1 andP. elongata exhibited similar shoot production, and both were more prolific thanP. fortunei. Shoot production per leaf fromP. elongata andP. Henan 1 could be greatly increased if petioles were cut in half and leaf laminae were cut into three strips, rather than leaving petiole and laminae explants intact. The growth regulator concentrations required for maximal shoot production differed among clones, but all required 0.2 or 0.5 mg/l naphthaleneacetic acid and 5.0 or 7.0 mg/l benzyladenine. The average adventitious shoot production after 4 weeks in culture for the two most prolific genotypes was 63 shoots per leaf fromP. Henan 1 and 48 shoots per leaf fromP. elongata.Abbreviations BA benzyladenine - NAA naphthaleneacetic acid - MS Murashige and Skoog Medium (1962)     

Micropropagation with a novel pattern of adventitious rooting in American sweetgum (Liquidambar styraciflua L.)

Liquidambar styraciflua L. has great potential not only as an ornamental, but also for its commercial importance in pulp and paper production or biomass energy. This study was designed to evaluate the influence of plant growth regulators on adventitious shoot multiplication from shoot tips, and in vitro adventitious rooting. The morphogenic capacity of intact leaves grown in vitro was also assayed for adventitious shoot formation and aerial root development. The highest shoot multiplication rate of 5.9 shoots per explant was achieved with 0.7 mg l⁻¹ 6-benzylaminopurine plus 0.01 mg l⁻¹ indole-3-butyric acid. Thidiazuron, alone or in combination with 6-benzylaminopurine, did not significantly support higher shoot multiplication rates. The organogenic ability of the in vitro grown leaves was significantly lower and slower in comparison with shoot tips. Microshoots rooted readily after transfer to a half-strength woody plant medium supplemented with 0.5–0.7 mg l⁻¹ 1-naphthaleneacetic acid, and were then successfully acclimatised to an ex vitro environment. A novel pattern of adventitious rooting was observed from the aerial parts of microshoots which were not in contact with the medium, including the parenchyma cells of the leaf blades as well as stem nodes and internodes. The regenerated plants established in soil did not show any detectable morphological variation.     

In vitro adventitious bud formation on isolated seedlings ofPinus silvestris L.

The formation of adventitious buds under the influence of 6BAP has been observed on various aerial organs of culturedPinus silvestris seedlings. The inductive power of this cytokinin was found to depend on the concentration and the physiological age of the explant.     

In vitro adventitious shoot formation from embryonic and cotyledonary tissues of Pinus brutia Ten.

Adventitious buds were induced when isolated whole embryos, and excised cotyledons from treated seeds of Calabrian pine (Pinus brutia Ten.) were cultured on a cytokinin-supplemented medium. The adventitious buds formed directly from the cotyledons. The highest number of bud primordia were formed, with both embryos and excised cotyledons, after 6 weeks on a BAP — supplemented Schenk and Hildebrandt medium under a 16 h photoperiod. The buds, when separated and maintained individually on a full-strength medium without growth regulators, developed into well-formed shoots within 4 weeks. The average number of harvested shoots obtained (>1 cm in height) per seed over 24 weeks was 55; however, a maximum number of 152 shoots was obtained from one individual over the same period. The shoot forming capacity of the meristematic tissue was not lost after seven harvests.     

The toxicity of antibiotics and herbicides on in vitro adventitious shoot formation of Pinus pinea L. cotyledons

Summary The toxicity of three antibiotics commonly used to eliminate Agrobacterium tumefaciens from plant tissue during transformation were tested to determine their effect on Pinus pinea L. morphogenesis. Cefotaxime and vancomycin at a dose of 250 μg ml⁻¹, as well as ticarcillin at 300 μg ml⁻¹, were essentially nontoxic to the culture and significantly enhanced regeneration and shoot development. Kanamycin, a widely used selection agent for plant transformation, strongly inhibited regeneration even at very low doses. On the contrary, phosphinothricin and its ammonium salt glufosinate in the commercial formulation Finale? proved to be the best selection agents because they were less toxic to stone pine cotyledons. Thus, they could be applied immediately after transformation to avoid escapes. Other schemes for selection and recovery of transgenic stone pine trees are discussed.     

An improved medium for adventitious shoot formation and callus induction in Beta vulgaris L. in vitro

Six sugarbeet (Beta vulgaris L.) lines (GWI-248, SPB-11, MonoHy 55, SMS-1, EL45 and FC607) were tested for regeneration. Shoot cultures were initiated in vitro from naked, sterilized embryos obtained from mature seed. Excised petioles from cultured shoots were plated on Gamborg's B5 medium and four modified Murashige and Skoog (MS) media. A medium containing MS inorganic salts supplemented with 0.4 mg/1 N⁶-benzyladenine, 0.1 mg/1 indole-3-butyric acid, ten vitamins and six amino acids, termed RV, was superior for both adventitious shoot and callus formation. Callus was observed only on RV medium and only on petioles that did not develop adventitious buds directly. Rooting of regenerated shoots and development of complete plants was accomplished by transfer to Gamborg's B5 medium with 5 mg/l indole-3-butyric acid as the sole phytohormone. The complete process of regeneration through adventitious shoot production took from 4 to 6 weeks from explants to rooted plants. The callus that formed on nonorganogenic petioles was regenerative when transferred to fresh RV medium. Regeneration from callus occurred mainly by shoot organogenesis but also by somatic embryogenesis at a low frequency.Abbreviations BA N⁶-benzyladenine - IBA indole-3-butyric acid Contribution from Missouri Agricultural Experiment Station. Journal Series No. 10394. University of Missouri, Columbia, MO 63873, USA Mention of trade or company name does not constitute a guarantee or warranty of the product by University of Missouri-Columbia or U.S.D.A. Agricultural Research Service and does not imply their approval to the exclusion of other products that may be suitable.     

The effect of leaf source and developmental stage on shoot organogenic potential of sweetgum (Liquidambar styraciflua L.) leaf explants

Leaf explants harvested from shoot proliferating cultures and intact plants of Liquidambar styraciflua Variegata were placed on solidified Woody Plant medium supplemented with 0.1 mgl^-1 (0.5 M) naphthaleneacetic acid and 2.5 mgl^-1 (11.1 M) benzyladenine to initiate shoot meristems directly. Leaves from intact plants produced over 4 times more adventitious shoots than leaves from in vitro shoots and had a greater tendency to form shoots on the lamina. The relative developmental age of leaf tissue used dramatically influenced the shoot organogenic response observed for leaf explants from intact plants of L. styraciflua Variegata and Moraine.-Leaves that were either 20% or 50% of full size and still actively expanding were superior to other developmental stages for shoot organogenesis. As developmental leaf age increased throughout the period of leaf expansion, the number of shoots forming on the petiole stub remained constant, whereas shoot formation on the lamina increased 8 fold. Shoots derived from Variegata leaves rooted well and grew normally as plants. Differences in rooting ability and plant size could be detected between groups that had been separated according to explant source (in vitro vs. intact plant) and the location of shoot formation (petiole vs. lamina).     

Influence of light on adventitious root formation in birch shoot culturesin vitro

The influence of light of different spectral composition and levels of irradiance (2-40 Wm-²) on adventitious root formation (ARF) in birch shoot segments was investigated. Spontaneous rooting of shoot segments occurred in segments with intact apical or axillary meristems. Concerning ARF shoot meristems could be substituted by application of auxin. The very low rooting percentage of shoot segments in darkness was improved considerably by auxin application. Irradiation of cuttings was a requirement for a high percentage of spontaneous rooting. The promoting effect of light was dependent on its spectral composition and was the highest under red followed by white and blue light. The low rooting response under blue light was enhanced almost to the red light level by shielding the root-forming cutting base from light.     

High frequency adventitious shoot regeneration from excised leaves ofPaulownia spp. cultured in vitro

High frequency, direct regeneration of shoots was induced in leaf cultures ofPaulownia tomentosa, P. fortunei x P. tomentosa andP. kawakamii. The optimum culture medium for the leaf explants derived from shoot cultures was Murashige-Skoog (MS) medium supplemented with 10 M indole-3-acetic acid and 50 M benzyladenine. Up to 40 shoots were obtained over a 4 month culture period from each leaf explant. Rooting occurred spontaneously in the shoots that were about 1 cm tall when subcultured on phytohormone-free MS medium. The plantlets could be transplanted successfully. Some of the transplantedP. tomentosa plantlets flowered in the greenhouse one year after transplanting. The protocol is suitable not only for rapid multiplication of the various species ofPaulownia, but also for analytical studies associated with adventitious shoot regeneration.     

Efficient plant regeneration from in vitro leaves and petioles via shoot organogenesis in Sapium sebiferum Roxb.

Sapium sebiferum Roxb. is a widespread and economically important multipurpose tree due to its high value in ornamental, and biodiesel production as well as medicine. A highly efficient in vitro plant regeneration system through direct shoot organogenesis was established for the first time from leaves and petioles of S. sebiferum. The results showed that plant growth regulators (PGRs), mechanical damage, explant orientation, explant source, and developmental stage had a strong influence on the in vitro morphogenesis of S. sebiferum. For shoot organogenesis from leaves, the highest adventitious shoot induction rate (96.67%) with 25.67 shoots per explant was obtained when mechanically damaged leaves (the first three leaf explants at the top, leaf #1–3) were cultured with the abaxial surface placed down on Murashige and Skoog (MS) medium containing 0.5 mg L^?1 thidiazuron (TDZ). For in vitro morphogenesis of petioles, the combination of 1-naphthylacetic acid (NAA) and 6-benzylainopurine (6-BA) played a key role in cell fate determination. All of the in vitro petioles produced adventitious shoots on MS medium containing 1.0 mg L^?1 6-BA and 0.1 mg L^?1 NAA, while they produced green calli on medium fortified with 0.5 mg L^?1 6-BA and 1.0 mg L^?1 NAA. The shoots were subcultured in medium fortified with 0.5 mg L^?1 6-BA and 0.1 mg L^?1 NAA for multiplication and elongation. The elongated shoots successfully rooted on half-strength MS (1/2 MS) medium fortified with 0.5 mg L^?1 indole-butyric acid (IBA) and 0.25 mg L^?1 indole-3-acetic acid (IAA), and the regenerated plantlets successfully acclimatized with a survival rate of 92.56% in the greenhouse. The genetic fidelity of in vitro regenerated plants was evaluated using inter simple sequence repeat molecular markers. The in vitro regenerated plants were found to be the true to their mother plant. This study will be beneficial for the large-scale propagation as well as the genetic improvement of S. sebiferum.

     

Growth and water relations of Liquidambar styraciflua L. in an urban park and plaza

Summary Growth and water relations of 10-year-old sweet gum (Liquidambar styraciflua L.) street trees were studied in sites with low and high potential evapotranspiration to determine how these differences are integrated by growth and water relations over time. The trees were located in the parking strip between the curb and sidewalk at a partially vegetated urban park and an urban plaza in Seattle, Washington. Crown size, and seasonal and diurnal stomatal conductance and water potential, as well as diurnal air temperature and humidity, were measured over 2 growing seasons. Yearly trunk growth since transplanting was measured from increment cores. Vapor pressure deficits and air temperatures averaged 18% greater at the plaza, but whole-tree water loss appeared to be much lower than the park trees due to more restricted stomatal conductance and crown size. In addition, yearly diameter increment declined progressively once the plaza trees were established in the existing soil several years after transplanting. Lower water potential in the plaza trees indicated greater internal moisture deficits than the park trees, and tissue analysis revealed lower nutritional status, particularly nitrogen. A manipulative study of water and fertilizer to several additional plaza trees showed an interaction between water and nutrient deficiencies in the coarse and shallow soil that apparently limited growth. Furthermore, soil limitations probably interacted with paved surface conditions over time by reducing nutrient recycling from leaf litter, and generating higher vapor pressure deficits that would contribute to prolonged stomatal closure. Restricted growth and water relations status of the plaza trees represented an equilibrium between chronic high-resource demand above ground and limited below ground.     

In vitro adventitious root induction in Antirrhinum majus L.

A broadly applicable method for the successful induction of root systems in a number of cultivars of A. majus has been determined. This involves a double filter-paper bridge with a liquid medium for root induction and allows the transfer of culture-grown plantlets to a glasshouse environment with minimal disturbance to the plant as a whole. 100% survival of transferred plantlets has been achieved with the inclusion of a few simple precautions upon shoot transfer and during the initial stages of plant establishment in vivo.     

‘孔府酥脆’枣试管苗离体叶片不定梢诱导和再生

Using in vitro leaves of Zizyphus jujuba ‘Kongfusucui’ plantlet as explants,effects of culture method,phytohormone proportion and culture time on induction rate of adventitious shoot from leaves and effects of sucrose concentrations in rooting media on rooting of adventitious shoot were studied.The results show that induction rate of adventitious shoot by two-step culture method(firstly cultured on medium Ⅰ for four weeks then cultured on medium Ⅱ for three weeks) is significantly higher than that by one-step culture method(cultured continuously on medium Ⅰ for seven weeks).Phytohormone proportion in medium Ⅰ has an obviously influence on induction rate of adventitious shoot,which gradually increases with increasing of TDZ concentration in medium Ⅰ.And adding 1.0 mg·L-1 TDZ in medium Ⅰ leads to induction rate with above 80%.With culture time prolonging(cultured for 1,2,3 or 4 weeks on medium Ⅰ,respectively),induction rate increases gradually.Sucrose concentration has a significant effect on rooting of adventitious shoot,sucrose with higher concentration(30 g·L-1) is beneficial to rooting.According to induction rate and growth status of adventitious shoot,it is determined that optimal culture method of adventitious shoot induction from Z.jujuba ’Kongfusucui’ leaves is two-step culture method,that is,leaves firstly cultured on WPM medium containing 1.0 mg·L-1 TDZ and 0.5 mg·L-1 IAA for four weeks,and then cultured on WPM medium containing 0.5 mg·L-1 IAA and 1.0 mg·L-1 GA3 till adventitious shoot produced.     

High-frequency plant regeneration via adventitious shoot formation from deembryonated cotyledon explants of Sesamum indicum L.

Sesamum indicum L. was used as an important oil crop in the world. An efficient protocol for in vitro plant regeneration via adventitious shoot formation from deembryonated cotyledon explants isolated from mature seeds of sesame is developed. Optimal medium for direct adventitious shoot formation was Murashige and Skoog (MS) medium with 22.2 μM 6-benzylaminopurin (BA) and 5.7 μM indole-3-acetic acid (IAA). Abscisic acid (3.8 μM ABA) and AgNO₃ (29.4 μM) were effective in enhancing the frequency of adventitious shoot formation. Preculture of cotyledon explants on high sucrose concentration (6–9%) for 2 wk and subsequent transfer to 3% sucrose enhanced the frequency of adventitious shoot induction. Root formation from the adventitious shoots was easily achieved on MS medium containing 2.7 μM of α-naphthalene acetic acid (NAA). Regenerated plantlets were acclimatized on sand and peat moss (1:1), showing 95% survival with subsequent flowering and seed set. We established the high-frequency plant regeneration via adventitious shoot formation in S. indicum L.     

Effect of genotype on in vitro adventitious shoot formation in Pinus radiata and correlations between pairs of phenotypic traits during in vitro shoot development

The influence of genotype at the family and clone levels on adventitious shoot formation in Pinus radiata was examined using the cotyledon tissue culture system. Twenty-nine full-sib and two selfed families were used. Family and clone influenced all in vitro traits assessed and final adventitious shoot formation significantly. Five families selected for the long-internode trait and two selfed families used in the study were of average performance when compared to all families. Correlations using family means or clone-within-family means showed that shoot production could be predicted based on measures of early culture health. Shoot production after 16 weeks was positively related to early embryo (6 days) and early culture (4 weeks) health. Shoot production could be improved by approximately 100% through family selection, but only limited additional improvements were obtained through early embryo selection.