Micropropagation of Stemona tuberosa Lour. –A Review

Shoot apex of Magnolia obovata Thunb. was cultured on the modified Murashige and Skoog's (MS) medium supplemented with the combinations of IBA and BAP or NAA and BAP in various concentrations. Multiple shoots were induced successfully on the half strength MS reducing nitrate to one fourth (1/4N-1/2MS) medium containing 4μM IBA and 5μM BAP after 40 days of culture. The multiple shoots obtained were divided into small nodal explants and further subcultured on fresh medium. Many axillary buds were induced from the explant after 20 days of culture, and they succeedingly grew actively and developed multiple shoots. Culturing the axillary bud together with the stem tissue was effective for facilitating the induction of multiple shoots.

A simple and efficient system was developed for the rapid in vitro multiplication of Baptisia australis using nodal explants derived from axenic cultures. Among the four cytokinins [benzylaminopurine (BA), kinetin, N6-(2-isopentenyl)adenine (2-iP) and zeatin] tested for axillary bud induction, BA at 4.4 µM proved to be the most effective treatment for induction of multiple shoots from nodal explants after six weeks. Supplementation of Murashige and Skoog (MS) and Driver and Kuniyuki walnut (DKW) media with a chelated iron source, ethylenediamine Bis (2-hydroxyphenylacetic acid) (FeEDDHA) and BA had a favorable effect on axillary bud proliferation from explants (apical buds and nodal segments) further improving the regeneration response as well as number of shoots induced. DKW media proved to be superior to MS for multiple shoot induction of B. australis. A combination of 4.4 µM BA and 23 µM of FeEDDHA in DKW produced a positive response resulting in 100% of nodal segments responding and regenerating 7.2 shoots per explant. The highest rooting percentage was observed on MS media containing 1 µM IBA. In vitro-rooted plants were successfully acclimated in a greenhouse with a survival rate of 97%. The micropropagation method described in this study has a potential for commercial multiplication of this horticultural plant.

Glehnia littoralis Fr. Schm. is very popular as a flavored wild vegetable and the roots are a useful crude drug. However, cultivation of Glehnia is extremely expensive because of the short harvest period. This work was conducted to clarify the propagability of Glehnia from different explants and mature embryos isolated from seeds. Only axillary buds formed about 30 shoots with good root formation in the medium containing BA 1-5 μM+NAA 5 μM. By mature embryo culture, about 40 shoots with 80% root formation per embryo explants were obtained on media containing BA 1 μM+NAA 5 μM. For callus formation from mature embryos, media containing 2, 4-D 1 μM or NAA 5 μM were best, showing that callus was formed from about 90% of embryo explants. Glehnia callus produced by embryo explants induced about 45 embryoids in suspension culture for 4 weeks when cultivated on medium containing 2, 4-D, Then, each embryoid formed about 30 shoots with roots in the MS solid medium. These multiple shoots with roots vigorously grew into plants following acclimatization. Thus, induction of multiple shoots derived from embryoids through calli, which were formed from one mature embryo, may be an effective method of mass producing Glehnia plants compared to formation of multiple shoots from axillary buds or mature embryos.

To establish an efficient plant regeneration system of Cassia mimosoides, the 10-day-old seedlings were used as explants for inducing lateral buds. Results showed that the addition of BA and NAA for different ratios on the basis of 1/2 MS could effectively induce the production of lateral buds. By adding different additional elements, it was found that the growth of lateral buds was longer and stronger on the medium of 1/2 MS + 3.0 mg/l BA + 0.1 mg/l NAA + 4.0 mg/l Gln or 1/2 MS + 3.0 mg/l BA + 0.1 mg/l NAA + 1.0 mg/l AgNO3. Meanwhile, cutting with the lateral buds of tissue culture seedling, the rooting rate could reach 77.8% when 1/2 MS medium contained 0.2 mg/l NAA, although the root length was shorter. When the regenerated strong seedlings were transplanted into the soil, the survival rate was over 75%. Therefore, the best medium for lateral bud induction using 10-day-old seedlings as explants in C. mimosoides was 1/2 MS + 3.0 mg/l BA + 0.1 mg/l NAA. The growth of lateral buds can be promoted by the appropriate concentration of Gln and AgNO3, and the best rooting medium was 1/2 MS contained 0.2 mg/l NAA. Bangladesh J. Bot. 52(2): 515-521, 2023 (June) Special

Seasonal influence on axillary bud sprouting and micropropagation of elite cultivars of mulberry

Silver nitrate induced MS media enhanced multiple shoot regeneration and in vitro flowering from axillary bud and leaf explants of Solanum nigrum (L.) an important antiulcer medicinal plant. Healthy axillary bud and leaf explants were inoculated on MS medium supplemented with BAP/Kn (1.0 - 2.0 mg/l) in combination with IAA/NAA (0.5 mg/l) and AgNO3 (0.1 - 1.0 mg/l). The explants were responded effectively and good regeneration frequencies were observed in all the combinations of silver nitrate tested when compared to control. Maximum number of multiple shoots (34.3) was found in leaf explants cultured on MS media supplemented with BAP (2.0 mg/l), NAA (0.5 mg/l) and AgNO3 (0.4 mg/l). These regenerated shoots were sub-cultured on to the flowering media. Maximum number of in vitro flowers (12) was obtained from axillary bud explants in BAP (2.0 mg/l), Kn (1.0 mg/l), IAA (0.5 mg/l) and AgNO3 (6.0 mg/l) supplemented media when compared to leaf (4) and control. All the in vitro raised shoots were transferred to rooting medium supplemented with NAA, IBA (1.0 - 2.0 mg/l) and AgNO3 (0.1 - 0.6 mg/l). The best rooting response (24.6) was observed in 2.0 mg/l IBA + 0.4 mg/l AgNO3. The well rooted plantlets were transferred to polybags containing soil + vermiculate in 1:1 ratio for hardening and finally the hardened plantlets were transferred to field conditions.

Legumes are very important species including herbs, shrubs and trees, they are cultivated worldwide for different economic uses.Parkiais genus belongs to the Legumefamily, Fabaceae. The most common known species are P. biglobosaBenth (African locust bean) and P. roxburghii (Tree Bean)which were introduced to Egypt since 1890. The population of the tree is rapidly declining as result conservation efforts is needed to prevent it from extinction. In an attempt to conserve this genetic resource, tissue culture studies were carried toestablish a callus culture of both plants from different explants and regeneration of the developed callus and to study the effect of explant type, media composition on the callus production and the regeneration. Apical bud,axillary bud and root explants from in vitro germinated seedlings of P. biglobosaBenthwere cultured on MS and B5 medium supplemented with (0.4., 0.8, 1.2, 1.6 or 2.0 mg l-1 NAA) + Glutamine 0.5 mg l-1 + Proline 0.5 mg l-1 + Casein 0.3 mg l-1 + 2,4D 2.5 mg l-1. Each medium was supplemented with 30 g l-1 sucrose, 3 g l-1 agar and PH 5.8.for callus induction .and (0.4.,0.8,1.2,1.6 or 2.0 mg l-1 NAA) + Glutamine 0.5 mg l-1 + Proline 0.5 mg l-1 + Casein 0.3 mg l-1 + 6-BAP 2 mg l-1. Each medium was supplemented with 30 g l-1 sucrose, 3 g l-1 agar and PH 5.8.for regeneration.The study presented here demonstrates the successful attempt at regeneration of plantlets of P. biglobosaBenth via indirect organogenesis.It can be concluded that the medium composition has a significant effect on the calli production together with the type of the explant which showed relatively higher significance. Seeds germination stage apical bud explants media 8 followed by media 10 showed the most favorable mean performances values for the studied characters, Number of days to callus initiation (day) , Callus weight (mg), Dead calli percentage (%),Albino plants percentage (%),Green plants percentage (%) and Root percentage (%). Moreover, axillary bud, showed remarkable increase in the mean performance of average. However, the overall response of MS medium was found to be superior to that of B5 medium. Explants cultured on MS medium fortified with combinations of 2,4-D and BAP induced rapidly proliferating calli that turned more friable and nodular.

Multiple plantlets in lateral bud and leaf explant in vitro cultures of pineapple

Plant regeneration was achieved from axillary bud, callus and somatic embryos of Dianthus caryophyllus cv.Yellow Dot Com from node and leaf explants cultured on Murashige and Skoog (MS) medium supplemented with plant growth regulators. The explant nodal cutting responded well for direct regeneration while leaf explant was selected for callus induction. The highest number of direct adventitious shoots were achieved with 9.08 μM TDZ and 5.37 μM NAA. The maximum callus induction was achieved with 2.06 μM 2, 4-D and 2.68 μM NAA. The calli derived from MS medium supplemented with 5.37 μM NAA and 2.27 μM TDZ were found to have maximum shoot regeneration potential. The highest number of calli producing shoots and average number of shoots per callus was recorded on MS medium supplemented with 9.12 μM zeatin and 5.07 μM IAA. The calli derived from leaf explants cultured on medium containing 2.06 μM 2, 4-D and 2.68 μM NAA were highly friable, had poor regeneration potential and were selected for cell suspension studies. The cultures were allowed to grow into micro-colonies in liquid medium and subsequently into embryogenic calli on semi-solid and solid MS medium which later differentiated into somatic embryos without growth regulators. Plantlets were obtained from in vitro derived shoots/somatic embryos with 60-80% survival after 30 day of transfer to pots. The plants regenerated from axillary buds, callus and somatic embryos were compared with mother plant to assess genetic fidelity using RAPD and 2.94%, 26.47% and 20.58% variation was observed, respectively.

SummaryThe effect of thidiazuron (TDZ) on the shoot production capacity of preconditioned explants of Castanea sativa Mill. was evaluated. Embryonic axes of chestnut were aseptically germinated for 14.d in Murashige and Skoog (1962) basal medium supplemented with 0.1.mg l±1 TDZ or 1.mg l±1 benzyladenine (BA) (preconditioning medium), and hypocotyl, epicotyl and cotyledonary node explants were then cultured on shoot-induction medium (basal medium containing 0.01.mg l±1 naphthaleneacetic acid in combination with different TDZ concentrations). After four weeks of culture the explants were transferred for a further eight weeks to media with low BA concentrations and no TDZ. Shoots were produced only by cotyledonary node explants which contain preformed meristematic tissue. Best shoot production, in terms of the proportion of explants producing shoots and shoot productivity per explant, was achieved by BA-preconditioned explants exposed to 1±2.mg l±1 TDZ. Fewer TDZ-preconditioned explants produced shoots, and more produced only callus. An histological study showed preconditioned explants to have an altered meristematic axillary region, with meristematic cell proliferation giving rise to expanded, flattened apical meristems and reduced leaf primordium differentiation. Upon shoot-induction treatment the proliferating meristems orginated multiple shoot buds without an intervening callus phase. Shoot elongation was achieved by culturing the original explants in Gresshoff and Doy (1972) medium supplemented with 0.05.mg l±1 BA. Shoots longer than 10.mm were subcultured separately to initiate clonal shoot cultures that were proliferated following the outgrowth of axillary shoots. Rooting frequencies greater than 75% were achieved by 16 of the 21 clones evaluated. Rooting capacity was not influenced by either the preconditioning medium or the shoot induction medium, but considerable variation was observed between clones (genotypes).

Miniature potted rose and Damask rose are important commercial plant cultivars in ornamental horticulture. Root suckers are common rose propagation method, but it is slow and seasonally dependent. In this survey, the propagation of nodal explants of these two species was studied through in vitro regeneration system. 16 and 24 different media were used for study of shoot and root regeneration respectively. The axillary buds were sprouted earlier in miniature rose than R. damascena. Shoot induction and proliferation (shoot ramification and growth) were observed 5 and 17 days after planting in miniature rose and 16 and 38 days in R. damascena respectively. The highest shoot proliferation obtained in media 3 and 7 in miniature rose, and medium 16 for R. damascena. These three media were recorded as optimal media with 100 % shoot proliferation. In these media, root initiation and growth of miniature rose (respectively after 78 and 92 days) was earlier than Damask rose (respectively 125 and 138 days). The successful rooting occurred in three and two media for miniature and Damask rose respectively. Rooting frequency was higher in the half strength MS liquid media than the others. Thus, cultivar potted rose as a modern species is propagated easier than old rose (R. damascena).

O presente trabalho teve como objetivo o estabelecimento de um protocolo de regeneração in vitro de mudas de Aspidosperma polyneuron (peroba-rosa), a partir de segmentos nodais de material juvenil. Brotações apicais de mudas de dois anos de idade foram desinfestadas com 0,25% de hipoclorito de sódio ou 0,05% de cloreto de mercúrio, durante 10 min, visando ao estabelecimento de culturas assépticas. A indução de brotações múltiplas foi realizada em meio de cultura WPM, suplementado com BAP, ZEA ou CIN (2,2-8,8 miM), no cultivo inicial e nos dois subcultivos subseqüentes. Para indução de brotações alongadas foram testadas as combinações de fitorreguladores: 2,25 miM de BAP, ZEA ou CIN, associadas com 1,25 miM de AIB. A indução de raízes foi avaliada com tratamentos em soluções de AIB (2,5-10 mM), durante 5 ou 15 min. As mudas enraizadas foram transplantadas para casa de vegetação. A desinfestação das brotações apicais foi eficiente com 0,25% de NaOCl ou 0,05% de HgCl2, durante 10 min, obtendo-se 72,89 e 84,10% de sobrevivência, respectivamente. As maiores taxas médias de regeneração de brotações axilares (4 a 5) foram obtidas em meio de cultura suplementado com ZEA ou BAP (4,4-8,8 miM), após o segundo subcultivo. Concentrações mais reduzidas de BAP ou ZEA (2,25 miM) e 1,25 miM de AIB proporcionaram, em média, três brotações mais alongadas (1,5-2,5 cm de comprimento). Tratamentos com soluções de 10 mM de AIB, durante 15 min, foram eficientes na indução de raízes (80%), e as mudas transplantadas apresentaram taxas de sobrevivência superiores a 90% em casa de vegetação.

Axillary buds were induced from immature shoot explants taken from terminal buds of branches from 29- and 34-year old ponderosa pines (Pinus ponderosa Dougl ex Laws). The effect of collection time, position on the donor tree from which the explants were taken, and plant growth regulators on axillary bud formation was investigated. Explants from branches taken in late October formed axillary buds, whereas explants from branches collected in February 1988 produced a large amount of callus. The ability to form axillary buds was significantly greater for explants from the upper crown than from the lower portion of the tree. Explant elongation occurred and basal needle primordia swelled on Murashige & Skoog media (MS) containing 2.2 μM 6-benzyladenine (BA) and 5.4 μM naphthalenacetic acid. When transferred to a MS medium containing 4.4 μM BA, 59% of explants formed axillary buds.

Visando aumentar a eficiência de estabelecimento in vitro dos porta-enxertos de videira `Jales' e `Campinas', foram conduzidos alguns experimentos com ápices meristemáticos e segmentos nodais, retirados de brotações de estacas lenhosas. Foram testadas diversas concentrações de 6-benzilaminopurina (BAP) em meio de cultura MS com a metade da concentração de sais. O efeito desta citocinina foi marcante sobre o crescimento dos explantes. O aumento da concentração de BAP estimulou o crescimento e expansão foliar dos ápices meristemáticos e das gemas axilares até a concentração de 10µM. O uso de 20µM de BAP reduziu o crescimento dos segmentos nodais. Conclui-se que o estabelecimento dos porta-enxertos pode ser realizado em meio MS, com a metade da concentração de sais, suplementado com 10µM de BAP.

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.