Micropropagation of Anogeissus latifolia (Roxb. Ex DC.) Wall,ex Guill. & Perr.- A Tree of Fragile Ecosystems

Abstract

A micropropagation process was developed for Anogeissus latifolia-a tree of fragile ecosystems. Multiple shoots were regenerated from cotyledonary node and epicotyl explants on Murashige and Skoog's (MS) medium containing 0.1 mgl^-1 indole-3-acetic acid (IAA) + 1.5 mgl ^-l 6-benzylaminopurine (BAP) + additives (25 mgl ^-l each of adenine sulphate, L-arginine, ascorbic-, citric acids and 1.0 mM L-asparagine) + 200 μM Fe-EDTA (ferric-ethylenediaminetetraacetic acid) salt. The shoots differentiated in vitro were subcultured and repeatedly transferred onto fresh medium but with 1.0 mgl^-1 of BAP to achieve 4-5 fold rate of shoot multiplication. After every 4th week of culture, from each culture bottle 8-10 shoots could be harvested for rooting. The shoots produced in culture were rooted in vitro on half strength MS medium with 1.0 mgl ^-l either of IBA (indolebutyric acid) or NAA (naphthaleneacetic acid). The shoots were pulse treated with combination (100 mgl ^-l each) of IBA and NOA (2-naphthoxy acetic acid) rooted ex vitro. The ex vitro root induction method is highly efficient and plantlets so generated could be acclimatized and pot transferred. The process developed can be used for large scale production of plants of A.     

An Efficient Micropropagation Protocol for High-Frequency Plantlet Regeneration from Liquid Culture of Nodal Tissues in a Medicinal Plant,Turnera ulmifolia L.

A highly efficient, stable, and cost-effective micropropagation protocol for the conservation of a medicinal plant Turnera ulmifolia L. was established from nodal tissues via multiple axillary shoot proliferation on using Murashige and Skoog’s (MS) liquid nutrient medium. To begin with, nodal explants were placed on agar gelled medium amended with 2.0 mg L^?1 6-benzylaminopurine (BAP) and 0.1 mg L^?1 indole-3 acetic acid (IAA) for shoot induction. Subsequently, elongation of regenerated shoots could be possible on liquid MS medium supplemented with 0.5 mg L^?1 BAP and Kin (kinetin) each along with 0.1 mg L^?1 IAA where high frequency of regeneration in terms of number of shoots (47.2 shoots/explant) was achieved. Furthermore, long and healthy shoots (4?5 cm in length) were rooted on agar gelled half-strength of MS medium supplemented with 2.0 mg L^?1 indole-3 butyric acid (IBA). Finally, in vitro regenerated plantlets were gradually acclimatized in the greenhouse and transferred to the field successfully.     

Micropropagation of Selected Genotype of Aloe vera L.—An Ancient Plant for Modern Industry

Aloe vera Linn. (Syn. Aloe barbadensis Mill; Gwar-patha in Hindi) belongs to family Liliaceae. The plant, for its medicinal properties, has commercial value. Some of the genotypes of Aloe vera are consumed as a vegetable and processed to make curry and other edible products. We report here on the development of an efficient method for rapid clonal propagation by shoot proliferation from axillary meristem(s) of selected germplasm of Aloe vera. Explants were pretreated with 0.1% aqueous solution of both streptomycin and bavistin separately, each for 15 min. These were surface sterilized with 0.1% aqueous solution of mercuric chloride (HgCl₂) for 4–5 min and washed several times with autoclaved water. These were kept in a chilled, sterile antioxidant (200.0 mg L^?1 of ascorbic acid, 50.0 mg L^?1 of citric acid, and 25.0 mg L^?1 of polyvinylpyrrolidone; PVP) solution and cultured on semi-solid Murashige and Skoog's (MS) medium. The bud explants produced multiple (10.3 ± 0.675/explant) shoots on MS medium containing 13.32 μM of 6-Benzylaminopurine (BAP) and 100.0 mg L^?1 of ascorbic acid, 50.0 mg L^?1 each of citric acid and PVP, with 25.0 mg L^?1 each of arginine and adenine sulphate as additives. The shoots were further multiplied by (a) repeated transfer to fresh MS medium with additives + 13.32 μM BAP, and (b) subculturing on MS medium with a lower (4.44 μM) concentration of BAP. On MS medium containing 4.44 μM of BAP and additives, a maximum number (27.8 ± 0.63) of shoots were produced. In liquid MS medium with 4.44 μM of BAP, the rate of shoot multiplication increased and the vigor of the shoots improved. One hundred percent of the cloned shoots rooted under in vitro conditions on hormone-free half-strength MS salts containing 200.0 mg L^?1 of activated charcoal at 32 ± 2°C. The cloned shoots treated with 2.46 mM of indole-3-butyric acid (IBA) or 2.473 mM of β-naphthoxyacetic acid (NOA) for 5 min rooted under ex vitro conditions in the greenhouse. The rooted plants were hardened in the greenhouse and stored under an agro-net house. The cloned plants were transferred under different field conditions at various sites in Western Rajasthan. These plants grew normally. The higher rate of shoot multiplication and easier approach of direct rooting and hardening make this method superior to the methods previously reported on cloning/tissue culture of Aloe species. From a single shoot bud, approximately 5000 plants can be produced within 180 days.     

Development of an efficient protocol for plant regeneration from nodal explants of recalcitrant bamboo (Bambusa arundinacea Retz. Willd) and assessment of genetic fidelity by DNA markers

The present study describes an efficient method for in vitro plant regeneration in B. arundinacea through axillary shoot bud proliferation. Nodal explants were excised, cultured on MS medium containing different concentrations of 6-benzylaminopurine (BAP), kinetin (KIN) (0.5–5.0 mg l^?1) alone and/or in combinations with KIN/BAP (0.5 mg l^?1). The highest frequency (91.5 %) of multiple shoot bud induction with maximum number of shoots (85 shoots/explant) was noticed on MS medium + 3.0 mg l^?1 BAP + 0.5 mg l^?1 KIN. The regenerated multiple shoots were elongated on MS medium + 4.0 mg l^?1 KIN + 2.0 mg l^?1 gibberellic acid (GA₃) with maximum shoot length (4.9 cm). The elongated shoots were transferred to MS medium containing indole-3 butyric acid (IBA; 0.5–5.0 mg l^?1) alone and/or in combination with 0.5 mg l^?1 KIN and BAP. Highest frequency of rooting (75 %) was obtained on half-strength MS medium + 2.0 mg l^?1 IBA + 0.5 mg l^?1 KIN. After hardening, the plantlets were shifted to the green house and subsequently established in the field conditions with 90 % survival rate. random amplified polymorphic DNA (RAPD) markers were used to evaluate the genetic stability of the regenerants. RAPD profiles generated from the regenerated plants were found to be monomorphic, similar to the control. Results confirmed that the regenerated plants were true-to-type in nature and the developed micropropagation protocol could be used for large scale plant production of B. arundinacea.     

Micropropagation of Vegetable Rennet (Withania coagulans [Stocks] Dunal)—A Critically Endangered Medicinal Plant

Withania coagulans (Stocks) Dunal (Solanaceae), popularly called vegetable rennet, is a critically endangered and highly valued medicinal plant. Overexploitation and reproductive failure forced the plant species toward the verge of complete extinction. We describe here the development of a simple, rapid, and cost effective in vitro micropropagation system for W. coagulans for mass-scale production of true-to-type plantlets using nodal shoot segments. Exactly 95.5 ± 0.34% explants responded within 8–10 days (d) and produced multiple shoot buds (4.1 ± 0.10 shoots of 2.95 ± 0.15 cm length) on 0.8% agar-gelled Murashige and Skoog's (MS) basal medium supplemented with 8.88 μM 6-benzylaminopurine (BAP), 0.57 μM indole-3-acetic acid (IAA), and additives (100 mg L^?1 L-ascorbic acid, 25 mg L^?1 each citric acid, adenine sulphate, and L-arginine). The shoots in cultures were multiplied by repeated transfer on MS medium with 4.44 μM BAP, 0.57 μM IAA, and additives. Further cultures were multiplied on a large-scale through the subculturing of shoot clumps differentiated in vitro, on MS medium supplemented with 1.11 μM BAP, 0.57 μM IAA, and additives. Maximum number (19.1 ± 0.28) of healthy (6.15 ± 0.25 cm) and viable shoots differentiated on this medium. The microshoots were rooted both in vitro and ex vitro. Exactly 67.3 ± 1.01% microshoots rooted in vitro within 25–30 d on agar-gelled half-strength MS salts supplemented with 29.52 μM indole-3-butyric acid (IBA) and 200 mg L^?1 of activated charcoal (AC). Alternatively, 73.8 ± 0.65% cloned shoots rooted on sterile soilrite (soilless compost and soil conditioner) under ex vitro conditions after pulse treatment with 2.46 mM IBA for 300 s. The clones of W. coagulans were hardened in a greenhouse within 40–45 d by slow and gradual exposure of plantlets from high relative humidity (RH; 70–80%) and low (26 ± 2°C) temperature to low RH (40–50%) and high (34 ± 2°C) temperature. The hardened plantlets were transferred to soil and stored in agro-net house with more than 90% survival rate. Replacement of pure and laboratory grade sucrose with commercial grade sugar, use of less expensive commercial grade agar-agar in culture medium, higher rate of shoot proliferation, single step ex vitro rooting, and hardening of plantlets in the greenhouse are advantageous features of the protocol. The micropropagation protocol defined here is reproducible, easy to follow, and would be helpful in large-scale restoration programs through true-to-type mass-multiplication of W. coagulans.     

Regeneration of <Emphasis Type="Italic">Melia volkensii</Emphasis> Gürke (Meliaceae) through direct somatic embryogenesis

Experiments were conducted to study plant regeneration through direct somatic embryogenesis using mature zygotic embryo and cotyledonary explants from seeds of Melia volkensii stored for <3 and >12 months. Explants were cultured on Murashige and Skoog (MS) medium supplemented with BAP, NAA and 2,4-D (0.5, 1.0 and 2.0 mg l⁻¹) alone, and BAP (0.5, 1.0, 2.0 and 4.0 mg l⁻¹) in combination with 2,4-D or NAA (0.2 and 0.5 mg l⁻¹). After 4 weeks in culture, up to 60% of cotyledonary explants from the seeds stored for <3 months produced direct somatic embryos on BAP (0.5–4.0 mg l⁻¹) in combination with 2,4-D (0.2 mg l⁻¹). The number of somatic embryos ranged from 5 to 14 per explant in BAP (0.5 mg l⁻¹) and 2,4-D (0.2 mg l⁻¹) combination. Only 20% of cotyledonary explants from seeds stored for >12 months produced somatic embryos. Mature zygotic embryos failed to produce any somatic embryos. Subcultures of somatic embryos from cotyledonary explants of seeds stored for <3 months formed clusters of shootlets on semi solid MS and 1/2 MS media. After 6 weeks of subculture on multiplication MS media augmented with BAP (0.5 mg l⁻¹) and IAA (0.2 mg l⁻¹), 70% of the shoot tips formed 4–7 shoots per explant. Up to 33% of the multiplied shoots were rooted in MS medium supplemented with 2.0 mg l⁻¹ IBA. Plantlets developed normally into seedlings in the greenhouse.     

Micropropagation of Vitex negundo L. and Random Amplified Polymorphic DNA Analysis of Micropropagated Plants

A micropropagation protocol was established for a medicinal plant Vitex negundo. Genetic stability of micropropagated plants was investigated. Multiple shoots were induced from nodal explants cultured on Murashige and Skoog (MS) medium with 0.53 μM naphthalene acetic acid (NAA) and 11.0 μM benzyl aminopurine (BAP) along with additives (ascorbic acid, 283.9 μM; citric acid, 130.1 μM; and arginine, 143.6 μM). Shoots were further multiplied by repeated transfer of the mother explant. The shoots were further multiplied on MS medium + 0.57 μM indole-3-acetic acid (IAA) and 6.6 μM BAP. The micropropagated shoots were pulse treated with 122.5 μM indole-3-butyric acid (IBA), in liquid MS medium and then transferred to autoclaved soilrite. These rooted ex vitro. Shoots were also rooted in vitro on a half-strength MS medium + 2.45 μM IBA. The survival rate of in vitro rooted plantlets was poor during hardening compared to ex vitro rooted plantlets. About 95% of the ex vitro rooted, hardened plantlets survived in the field. Genetic stability of micropropagated plants was tested by using 25 random amplified polymorphic DNA primers. The cloned plants exhibited no variation in banding pattern in comparison with the mother plant.     

Rapid Micropropagation of Edible Bamboo Dendrocalamus asper

Abstract

Micropropagation protocols for Dendrocalamus asper using nodal shoots and seeds culture are described. Multiple shoots were induced through forced axillary branching. Ninety-five percent of the nodal shoot explants taken from juvenile primary and lateral branches, produced multiple shoots through axillary buds activation within 2 to 8 weeks on Murashige & Skoog's (MS) medium supplemented with 0.1-15 mg/l benzyladenine (BA). The cultured seeds also produced multiple shoots (1-20) within 6 weeks on this medium. The multiple shoot differentiation was influenced by the concentration of BA in the medium. The in vitro generated shoots were excised and subculture on MS + 3.0 mg/l BAP for further shoot multiplication. Fifteen to 20 fold rate of shoot multiplication was achieved by regular subculturing. These shoots were multiplied for more than 3 years without loss of vigor. Ninety-five percent of the shoots were rooted, when propagules (each consisting of cluster of 3 shoots) were transferred on to MS medium with 3.0 mg/l NAA or 10 mg/l indole-3-butyric acid (IBA).

To date, 18,000 plants (through axillary bud initiated from nodal ex-plants) and 6,000 plants from seed culture have been hardened and acclimatized. 12,000 plants have been field transferred.     

In vitro propagation of Acacia sinuata (Lour.) Merr. via cotyledonary nodes

Acacia sinuata is a valuable multipurpose tree in Southern India. The tree is over exploited, but its regeneration rate in natural habitat is low. Therefore, it is important to study if it can be regenerated through in vitro micro-propagation. Cotyledonary node and shoot-tip explants excised from 15 day-old in vitro grown seedlings were used to initiate cultures. Maximum number of shoots was induced from cotyledonary node explants on Murashige and Skoog's (MS) medium containing6.66 µM 6-benzylamino purine (BAP) and 4.65µM kinetin (Kn). Subculturing was done in the fresh medium of same composition. The number of shoots formed was comparatively greater in the first subculture. Maximum shoot elongation was achieved (5.5 cm)when subcultured on MS medium supplemented with 1.75 µMgibberellic acid (GA₃). In vitro regenerated shoots produced roots when transferred to half strength MS medium supplemented with 7.36 µM indolebutyric acid (IBA). From each cotyledonarynode 30 shoots were obtained within 90 days after two subcultures. The success rate of establishing the rooted plantlets in the field was 55%.This revised version was published online in November 2005 with corrections to the Cover Date.     

In Vitro Propagation of the Important Tasar Oak (Quercus serrata Thunb.) by Casein Hydrolysate Promoted High Frequency Shoot Proliferation

An efficient micropropagation protocol has been developed for tasar oak. Nodal segments from in vitro grown seedling were used for shoot multiplication. Best shoot multiplication response, in terms of number of shoots per explant as well as shoot length, was obtained in woody plant (WP) medium supplemented with 6-benzyladenine and indole-3-acetic acid (8.88 μM BA + 1.43 μM IAA); but the establishment of cultures was difficult due to basal callus formation and necrosis in due course of time. Out of the two used growth adjuvants, casein hydrolysate (CH, 500 mg L^?1) promoted shoot multiplication rate significantly in comparison to silver nitrate and also eliminated the basal callus formation problem and necrosis faced during the later stage of shoot proliferation. In vitro rooting on WP medium supplemented with 100 μM indole-3-butyric acid (IBA) when applied for 48 hr gave the best results in comparison to prolonged exposure. Well-acclimatized plantlets were transferred to the field with 80% survival rate. This protocol could be useful not only to propagate and conserve this oak but can also uplift the socioeconomic status of the Himalayan people as its leaves are used to feed the tasar silk worm during rearing period. This method will also be helpful for propagation of high value trees for a reforestation program.     

Clonal propagation ofGmelina arborea Roxb. byIn vitro culture

In vitro propagation technique ofGmelina arborea multipurpose and a fast growing tree species was studied. Nodal segment including axillary bud was used as a explant. They were cultured on MS media containing various concentrations (0–10 mg/l) of BAP alone or in combination with 0.002 mg/l of IBA. Nodal segments showed axillary bud proliferation in almost all media tested. MS media containing 0.22 mg/l of BAP alone and 2 mg/l of BAP in combination with 0.002 mg/l of IBA were effective for inducing multiple shoots and shoot elongation. MS medium supplemented with 0.02 mg/l of NAA and 1 mg/l of IBA gave the best result for rooting. The regenerated plantlets were potted and acclimatized successfully in a growth chamber and then moved to the green house. Adventitious shoots production from stem explants that were taken from regenerated plantletin vitro was also discussed. Stem segments were tested for their morphogenetic potential on MS media with various combinations and concentrations of BAP, zeatin and TDZ. Successfull result was obtained on MS media supplemented with 2 mg/l of BAP and 1 mg/l of zeatin or supplemented with 0.5 mg/l of BAP and 0.5 mg/l of TDZ. The shoots obtained on MS media containing 2 mg/l of BAP and 1 mg/l of zeatin rooted on MS media containing 0.02 mg/l of NAA and 1 mg/l of IBA, and plantlets were successfully obtained. A part of this paper was presented at the 109th Annual Meeting of the Japanese Forest Society (1998).     

Efficient method of micropropagation and in vitro rooting of teak (Tectona grandis L.) focusing on large-scale industrial plantations

Multiple shoots of high quality were produced in vitro from nodal expiants of Tectona grandis. An average of about 4 shoots/uninodal expiant was obtained within 4 weeks of culture on Murashige and Skoog’s (mMS) medium modified by 50% reduction in NH₄NO₃ concentration, supplemented with benzylaminopurine (1.5 mg L^?1); indole-3-butyric acid (0.01 mg L^?1) and gibberellic acid (0.1 mg L^?1). The latter was applied both in the medium and by soaking the nodal segments for 10 s. in a gibberellic acid solution of 100 mg L^?1. Hundred percent of shoots rooted cultured on modified MS medium containing IBA (0.5 mg L^?1) and putrescine (160 mg L^?1). Putrescine promoted both strong and highly ramified roots and fast growing shoots during the rooting phase, conditioning the plantlets for a good survival and quality. Plantlets were transferred to jiffy pots for a short acclimatization stage in greenhouse where they survived at 100%. This highly reproducible procedure can be adopted for large scale teak propagation.     

In vitro propagation of a medicinal plant: Tripterygium wilfordii Hook f.

In this study a reliable protocol was developed for the establishment of commercial in vitro cultures of Tripterygium wilfordii Hook f.. Juvenile shoots from one-year-old elite plants were used as the source of explants. New axillary shoots were obtained after 30 days of culture on a MS medium supplemented with BAP (2.0 mg·L^–1) and NAA (0.1 mg·L^–1). The optimal multiplication medium was a modified MS medium supplemented with BAP (1.0 mg·L^–1) and NAA (0.1 mg·L^–1). This yielded a multiplication rate of 2.4 for each subculture. Slightly more than 92% of shoots rooted when cultured on a modified MS medium containing IBA (0.2 mg·L^–1) and acti-vated charcoal (0.5 mg·L^–1). Activated charcoal promoted both a strong and a high rooting rate during the rooting phase. Plantlets were transferred to pots for a short acclimatization stage in a greenhouse where 95% of the plantlets survived. This highly reproduci-ble procedure can be adopted for large-scale propagation of T. wilfordii.     

Micropropagation of Salvadora oleoides—An Oil Yielding Tree of Arid Forests

Salvadora oleoides is an ecologically important multipurpose tree of the arid forest that occurs in saline areas of northwest India. The seed of this plant yields non-edible commercially usable oil. Poor seed germination, low seed viability, and increasing industrialization are some of the constant factors which significantly affect the status of the natural population of this plant. Therefore, there is a great need to develop an efficient propagation system using the tissue culture technique. In the present communication, we demonstrate the development of an in vitro propagation system for S. oleoides. Multiple shoots were induced from nodal segments harvested from about 25- to 30- yr-old lopped trees of S. oleoides on MS medium + 0.1 mg L^?1 NAA (Naphthalene acetic acid) + 2.5 mg L^?1 BA (6-Benzylaminopurine) + additives. The shoots were multiplied by (a) repeated transfer of the mother explants on MS medium + 1.0 mg L^?1 BA + 0.1 mg L^?1 NAA + additives and (b) subculturing of shoot on MS + 1.0 mg L^?1 BA + additives. About 84% shoots rooted ex vitro on soilrite within 3–4 weeks when base (4–5 mm) of shoots was treated with 100 mg L^?1 of IBA (Indole-3-butyric acid) for 5 min. The plantlets were hardened successfully in the greenhouse and transferred to the pots and field. To the best of our knowledge, this is the first report of a regeneration protocol for S. oleoides from explants obtained from mature trees. Use of the ex vitro rooting technique for plant production serves as a more economical option as it reduces labor, cost, and time. We suggest that the methods developed and described in this article can be used for large-scale plant production and conservation of germplasm of this tree species.     

In vitro plantlet regeneration from Australian Red Cedar (Toona ciliata,Meliaceae)

In vitro regeneration of complete plants from nodal single-bud segments of 2-year-old Australian Cedar (Toona ciliata) trees were obtained under defined nutritional and environmental conditions. Explants were dissected from plants obtained by germination of seeds and growth in pots in a greenhouse. The best medium for shoot regeneration was that of Murashige and Skoog at 1/4 strength with 3% sucrose (1/4 MS), supplemented with 0.1 mg/l IBA and 0.5 mg/l BAP. Rooting of regenerated shoots was observed in MS medium with 0.1 mg/l IBA. Using mature tree material was more difficult. Forced flushing was used to induce shoot development on branches of a 10-year-old tree. Nodal segments of these epicormic shoots formed shoots in vitro on 1/4 MS + 0.01 mg/l IBA + 5 mg/l BAP, but rooting was never observed.     

Plantlet regeneration from leaf protoplasts ofPopulus euphratica

Protoplasts were isolated from the leaves of sterile plants ofPopulus euphratica Oliv. by using 1% Cellulase “Onozuka” RS and 0.25% Pectolyase Y-23 in 0.6m of mannitol solution. Protoplasts were cultured in modified Murashige and Skoog's (MS) medium which contained no ammonium ions but was supplemented with BAP (6-benzylaminopurine), 2,4-D (2,4- dichlorophenoxy-acetic acid), and 1% sucrose at the cell density of 9×10⁴/ml. Cell divisions occurred in every culture medium, especially in the medium containing 0.5 mg/l of BAP and 0.1 mg/l of 2,4-D, in which callus was successfully induced by successive culture through cell cluster formation. Shoots were regenerated from the callus, and their growth was enhanced on 1/2 MS medium containing 0.8 mg/l of BAP. Finally, shoots were rooted and plantlets were regenerated on 1/2 MS medium without a hormone. A part of this paper was presented at the 106th Annual Meeting of the Jpn. For. Soc. (1995).     

Effect of auxin,cytokinin, and glutamine on mycelial growth of Phaeolus schweinitzii

The effect of naphthaleneacetic acid (NAA), benzylaminopurine (BAP), L-glutamine (L-gln), and combinations of these substances on mycelial growth of Phaeolus schweinitzii was studied in vitro. NAA (1 mg × 1^?1), L-gln (500 mg × 1^?1) and a combination of NAA with L-gln inhibited the growth of fungal mycelium. BAP (1 mg × 1^?1) enhanced the inhibitory effect of NAA while in combination with L-gln it reduced the inhibitory effect of L-gln.     

In vitro clonal propagation of Gardenia latifolia Ait.: a toy making woody tree

An efficient, in vitro clonal propagation protocol has been established for Gardenia latifolia Ait. using mature nodal explants on Murashige and Skoog (MS) medium fortified with cytokinins (BA/Kn/2-iP) (1.0–5.0 mg l^?1) in combination with auxin IAA (0.5 mg l^?1). Maximum bud break (87 %) with shoot number (7.2 ± 0.26) observed on MS medium supplemented with BA (4.0 mg l^?1) and IAA (0.5 mg l^?1). Maximum number of shoots (30 ± 0.46) with shoot length of (0.9 ± 0.03 cm) observed on MS medium supplemented with BA (2.0 mg l^?1), Kn (2.0 mg l^?1) and IAA (0.5 mg l^?1). Further elongation of shoots (3.5 ± 0.06 cm) was achieved on MS medium supplemented with BA (1.0 mg l^?1) and IAA (0.1 mg l^?1). About 70 % of root induction occurred in half-strength MS medium supplemented with IBA (4.0 mg l^?1) in 4–6 weeks. Further elongation of roots with average length (9.0 cm) was achieved in culture bottles containing vermiculite and ¼ strength MS salts. After their partial hardening in these bottles for 30 days they were transferred to pots containing a mixture of soil and vermicompost (1:1) for acclimatization. The acclimatized plantlets were established in the field successfully with 85 % survival rate.     

Induction of somatic embryogenesis and analysis of genetic fidelity of in vitro<Emphasis Type="Italic">-</Emphasis>derived plantlets of <Emphasis Type="Italic">Bambusa nutans</Emphasis> Wall., using AFLP markers

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.     

Somatic embryogenesis and plant regeneration inAcanthopanax sciadophylloides

Somatic embryos ofAcanthopanax sciadophylloides Franch. et Sav. were differentiated from both zygotic and somatic embryos and calli, and plants were regenerated from these somatic embryos. A zygotic embryo, enclosed within a small portion of the endosperm, was incubated on Murashige and Skoog (MS) media supplemented with various combinations (range 0–10.0 mg/l) of 6-benzylaminopurine (BAP) and 2,4-dichlorophenoxyacetic acid (2,4-D). After 4 months, swelling of the zygotic embryos and callus formation was observed. When the swollen embryos were transferred to MS medium supplemented with 0.5 mg/l of 2,4-D, somatic embryos were formed in one to two months. After subculture on the same medium, new embryos were differentiated from various parts of the older somatic embryos. The calli were cultured on medium supplemented with 2.0 mg/l of 2,4-D and BAP for three weeks. Proliferated calli were transferred to medium supplemented with 1.0 mg/l of 2,4-D and BAP. Somatic embryos were differentiated from the calli within one to two months. Somatic embryos were germinated on half-strength MS medium without plant growth regulators and the plantlets were grown in soil. A part of this paper was presented at the 106th Annual Meeting of the Japanese Forestry Society (1995) & First Asia-Pacific Symposium on Forest Tree Genetic Improvement (Beijing).