Induction Of Direct Somatic Embryogenesis Research Articles

Induction of direct somatic embryogenesis and genetic stability of somatic embryo-derived plants of broccoli

Induction of direct somatic embryogenesis and genetic stability of somatic embryo-derived plants of broccoli

Effects of basic media and plant growth regulators on Direct-somatic embryogenesis induction in vegetative strains obtained from the tissue culture of digitalis purpurea

This study aimed to investigate the effects of certain nutrient medium types enhanced with plant-growth regulators on the direct inductionof somatic embryogenesis in vegetative strains produced and propagated from a tissue culture of Digitalis purpurea. The results showthat MS medium was superior to other tested nutrient media-B5, LS, and 5C01—in terms of the days required to initiate direct somaticembryogenesis induction and induction rate. In contrast, the LS medium resulted in the highest number of embryos. Moreover, 2 mg/LBA (benzyl adenine) was superior to similar concentrations of BAP (benzyl aminopurine) and Kin (kinetin) in the MS medium, whereasBAP performed better in LS and B5. On the other hand, auxin 2.4D (dichlorophenoxy acetic acid) inhibited somatic embryogenesis, as didNAA (naphthalene acetic acid) and IAA (indole acetic acid) when added individually. Regarding the type of explant, the stems showedthe induction rates and numbers of direct-somatic embryos produced in all the basic media.Keywords: Digitalis purpurea; Vegetative strains; Direct-somatic embryogenesis; Explant; Basic media

Induction of direct somatic embryogenesis and shoot organogenesis and histological study in tree peony (Paeonia sect. Moutan)

Tree peony (Paeonia sect. Moutan) is a world famous ornamental and economically important species, but it is recalcitrant to in vitro regeneration. Here, we present a protocol for induction of direct somatic embryogenesis (SE) and direct shoot organogenesis (SO) from zygotic embryos (ZEs) of Paeonia rockii and P. ostii. The results showed that explant genotypes, ZEs stages, sucrose and plant growth regulators (PGRs) have greatly influences on in vitro morphogenesis. The highest frequency of SE (48%) and mean number of somatic embryos (5) was obtained from mature ZE of P. rockii ‘Jing Hong’ when cultured on modified Murashige and Skoog (mMS) medium supplemented with 2.22 µM BA and 0.23 M sucrose.The proliferation can be achieved by recurrent production of embryogenic callus and somatic embryos on mMS medium supplemented with 0.89 µM BA. The germinated rate of somatic embryos was 45% on WPM medium containing 2.22 µM BA and 1.44 µM GA3 after dormancy release at 4 °C under dark for 20 days. In addition, direct SO was obtained firstly in tree peony by using a variety of cytokinins. Morpho-histological analysis confirmed the initiation, development and reserve accumulation of somatic embryos and shoots. The study will be benificial to the propagation and breeding of tree peony. Tree peony (Paeonia sect. Moutan) is a world famous ornamental and economically important species which is recalcitrant to in vitro regeneration. Direct somatic embryogenesis protocol of P. rockii ‘Jing Hong’ was developed and morpho-histological analysis confirmed the initiation, development and reserve accumulation during in vitro morphogenesis. The study will provide valuable reference for propagation and breeding of tree peony.

Brassinosteroid increases the cytokinin efficiency to induce direct somatic embryogenesis in leaf explants of Coffea arabica L. (Rubiaceae)

The combination of different plant growth regulators can result in beneficial effects in the induction of in vitro morphogenetic pathways. The present study reports the effect of 24-epibrassinolid (24-epiBR; brassinosteroid) when added alone and in association with N6-(2-isopentnyl) adenine (2-iP; cytokinin) in the induction of direct somatic embryogenesis in Coffea arabica. Leaf explants were cultivated in a modified Murashige and Skoog (MS) medium with 0 or 10 µM 2-iP and different concentrations (0.01, 0.10 or 1.0 µM) of 24-epiBR. Explants cultured on MS medium supplemented with 1.0 µM 24-epiBR in association with 2-iP produced 6.8 times more somatic embryos than the explants cultured with only 2-iP. Histological analyses also provided evidence that the supplementation of brassinosteroids in the culture medium could have influenced somatic embryogenesis differentiation. Somatic embryos obtained in the presence of brassinosteroid and cytokinin were better structured morpho-histologically as compared to those obtained in the medium with just cytokinin. This study opens new perspectives for the use of brassinosteroids in the somatic embryogenesis of C. arabica, so as to optimize the in vitro regeneration systems used in genetic improvement programs in C. arabica productive systems.

Somatic embryogenesis and in vitro flowering in Hybanthus enneaspermus (L.) F. Muell. – A rare multipotent herb

Present study reports the various factors affecting somatic embryogenesis and in vitro flowering in Hybanthus enneaspermus (L.) F. Muell. The effect of the salts strength of Murashige and Skoog's (MS) medium, concentration of sucrose and plant growth regulators were analyzed for the induction of direct somatic embryogenesis using nodal segments as explants. High frequency of somatic embryogenesis was reported on full strength MS medium (with 3% sucrose) and additives supplemented with 0.5 mg/L 6-benzylaminopurine (BAP) and 0.25 mg/L indole-3-acetic acid (IAA). Maximum somatic embryos (207.0 ± 4.2) were germinated on 1/2 strength MS medium augmented with 0.5 mg/L BAP. Microscopic studies revealed the typical developmental patterns in somatic embryogenesis from globular to heart-shaped and followed by bipolar torpedo-shaped somatic embryos from nodal explants. The plantlets raised from the somatic embryos resulted in flowering on full strength MS medium augmented with 1.0 mg/L each of BAP and Kinetin (Kin) + 0.5 mg/L IAA at 50 μmol/(m2·s) SFPD for 13 h/d photoperiod. About 92% plantlets were successfully acclimatized in the greenhouse. Field transferred plants exhibit normal flowering and fruit setting. The study could be exploited for large scale propagation of true to type plants as conservation strategies of this rare and endemic medicinal plant.

Direct somatic embryogenesis of Malaxis densiflora (A. Rich.) Kuntze.

A protocol for induction of direct somatic embryogenesis and subsequent plant regeneration for the medicinally important and endangered plant of Malaxis densiflora has been developed for the first time. In the present study, in vitro seed derived protocorm explants were cultured on half strength Murashige and Skoog (MS) medium supplemented with 2,4-dichlorophenoxyacetic acid (2,4-D), Picloram and Dicamba individually and in combination with cytokinins BAP, TDZ and Kn for its effectiveness to induce the differentiation of somatic embryos. The best response was observed in protocorms cultured half strength MS medium supplemented with 2,4-D at 3.39 μM and TDZ at 6.80 μM. Both epidermal and sub epidermal cells were involved in the formation of embryos. The proembryos developed into globular stage and subsequently developed into protocoms. Complete plantlets were formed after 60 days of culture. The plantlets were acclimatized in plastic pots containing sterilized vermiculite. The survival rate was 76%.

English

Eurycoma longifolia is one of the well-known herbal plants in Southeast Asian region due to its remarkable properties, especially the root part that can be used as aphrodisiac, anti-cancer, anti-malaria and anti-ulcer agent. Uncontrolled harvesting of this plant has reduced its population. Thus, an efficient protocol involving the induction of direct somatic embryogenesis from cotyledon culture of E. longifolia has been developed. 15% explants forming embryos were achieved on Modified Murashige and Skoog’s (MMS) medium supplemented with 0.1 mg/L zeatin plus 0.2 mg/L indole-3-butyric acid (IBA). However, the addition of 0.12 mg/L thidiazuron (TDZ) has increased the percentage up to 22.0%. The maturation phase occurred in the same medium, thus decreased the frequency of subculture and the genetic instability of the embryos. Secondary somatic embryogenesis growth of 20%, which was the highest percentage of growth, was achieved from the primary embryos that were cultured in the MMS medium with the treatment of 2.0 mg/L IBA plus 0.075 mg/L TDZ. The results indicated that the direct somatic embryogenesis obtained can be further used to develop a protocol for plantlet regeneration of E. longifolia.

Plant regeneration through direct somatic embryogenesis, antioxidant properties, and metabolite profiles of Swertia corymbosa (Griseb.) Wight ex C.B. Clarke

A protocol for induction of direct somatic embryogenesis and subsequent plant regeneration for the medicinally important and endangered plant of Swertia corymbosa has been developed for the first time. In the present study, in vitro derived leaf explants were cultured on Murashige and Skoog (MS) medium supplemented with 2,4-dichlorophenoxyacetic acid (2,4-D) individually and in combination with cytokinins for its effectiveness to induce the differentiation of somatic embryos. The antioxidant activities of methanolic extracts from non-embryonic callus (NEC), pre-embryoid masses (PEM), somatic embryos at globular stage (SEG), somatic embryos at heart-shaped stage (SEHS), and cotyledonary embryos (SEC) of S. corymbosa were evaluated using three in vitro assays: scavenging of free radicals (DPPH and ABTS) and ferric reducing antioxidant test. In all cases, the methanolic extract from SEG demonstrated better antioxidant activity than those taken from other tested samples. Higher amounts of swertianin (1), methylswertianin (2), and 1,2- dihydroxy-6-methoxyxanthone-8-O-β-D-xylopyranosyl (3) were found in SEG stage followed by SEHS and PEM when compared to NEC and SEC.

Plant regeneration through direct somatic embryogenesis from immature zygotic embryos of the medicinal plant, Paris polyphylla Sm.

A protocol for induction of direct somatic embryogenesis and subsequent plant regeneration for the medicinally important and endangered plant Paris polyphylla Sm. has been developed for the first time. Immature zygotic embryos (IZEs) were cultured on different media namely Gamborg (B5), ½ B5, Murashige and Skoog (MS), ½ MS, Chu et al. (N6), ½ N6, Schenk and Hildebrandt (SH) and ½ SH. Highest frequency of somatic embryogenesis (32.6 %) and mean number of somatic embryos (SEs) per explant (28.7 ± 1.7) were obtained on ½ MS medium directly without an intermediate callus phase. The frequency of SE induction was significantly increased to 40.7 % when ½ MS medium was solidified with gelrite compared to agar (32.6 %). Secondary somatic embryos (SSEs) appeared on the primary SEs in a repetitive way on plant growth regulator-free ½ MS medium but with a gradual decrease in embryogenic potential during subsequent subcultures. Plasmolyzing pre-treatment of SSEs with 1.0 M mannitol for 12 h effectively maintains its embryogenic capacity. Primary embryos at the elongated dimpled and early cotyledonary stage displayed the highest embryo forming capacity of 26.94 and 27.87, respectively. High frequency of SE germination (94.0 %) occurred on ½ MS medium with 0.5 mg/l gibberellic acid. Highest percentage of seedling to plantlet conversion was observed in the medium supplemented with 0.05 mg/l 6-benzylaminopurine and 0.1 mg/l α-naphthalene acetic acid. Regenerated plants displayed morphological characteristics similar to that of the wild plants. Flow cytometry analysis showed ploidy stability of the regenerated plants.

High frequency somatic embryogenesis and plant regeneration from hypocotyl and leaf explants of gherkin (Cucumis anguria L.)

Gherkin (Cucumis anguria L.) is an important commercial vegetable crop. An efficient protocol for plantlet regeneration from hypocotyl and leaf explants through direct somatic embryogenesis was developed. High frequency of somatic embryos (21.6 and 34.0) were obtained from hypocotyl and leaf explants when cultured on Murashige and Skoog (MS) salts plus B5 vitamins (MSB5) supplemented with 5% sucrose, 1.5mgL−1 2,4-D, 0.5mgL−1 BAP and 150μM l-glutamine. Initial culturing of embryos in the dark conditions for two weeks, followed by four weeks under light resulted in a higher frequency of embryo formation when compared to continuous light conditions. Histological observation showed that the somatic embryos originated from single cells of the epidermal layer. Histological evidence on formation of shoot and root poles during conversion of the embryos confirmed that these structures were true somatic embryos. Maturation of somatic embryos occurred on plant growth regulator-free MSB5 semi-solid medium containing 3% sucrose and 0.5% (w/v) activated charcoal (AC). Conversion of embryos into plantlets was achieved on MSB5 medium supplemented with 3% sucrose, 0.3% AC and 0.5mgL−1 gibberellic acid (GA3). Sucrose was found to be the best carbon source for SE induction, maturation and germination. Ninety percent of embryos were converted into normal plantlets. The plantlets were successfully acclimatized in the greenhouse with 95% survival rate and transferred to ex vitro conditions which developed with normal phenotypes. This regeneration protocol assured successful embryo induction and plantlet conversion. This is the first report for the induction of direct somatic embryogenesis from hypocotyl and leaf explants of C. anguria. The result of this study is beneficial for genetic transformation and mass clonal propagation.

Direct somatic embryogenesis of Agave fourcroydes Lem. through thin cell layer culture

Here, we describe a new protocol for the induction of direct somatic embryogenesis of Agave fourcroydes through thin cell layer (TCL) culture technology. The protocol was optimized for the main factors known to affect the process, including the type of explant (stem or leaf tissue), type and concentration of exogenous growth regulators (α-naphthalene acetic acid [NAA], 2,4-diclorophenoxyacetic acid [2,4-D], 4-amino-3,5,6-trichloro-2-pyridinecarboxylic acid [picloram], and 3,6-dichloro-2-methoxybenzoic acid [dicamba]), and the influence of plant genotype. Thin tissue segments cut transversally (tTCLs) from stems of in vitro-cultured plants gave the best embryogenic response when cultured with 2.26 μM dicamba (92.22 embryos/explant) or 2.07 μM picloram (81.72 embryos/explant). It was interesting to observe that the embryogenic capacity of these tissues was affected by the presence of 6-benzylaminopurine (BA) in the culture medium in which the explant donor plantlets were maintained. Thirteen clonal lines (each derived from a different parental plant), compared for their embryogenic competence under the same culture conditions, produced very different embryogenic responses that varied from very high (117 embryos/explant) to null. The histological analysis revealed that the amount of meristematic tissue present in the tTCLs varied according to the region of the stem (apical, middle, or basal) from which they originated. The cells of the vascular procambium became competent and developed into cell lines that formed embryos, either by a unicellular or a multicellular pathway. Mature embryos germinated in half-strength Murashige and Skoog medium without growth regulators and 85% of regenerated plants was successfully acclimatized in a greenhouse.

Direct somatic embryogenesis and plant regeneration from seed derived protocorms of Cymbidium bicolor Lindl.

A protocol for the induction of direct somatic embryogenesis from seed derived protocorms was developed in Cymbidium bicolor. Ninety-day-old protocorms cultured on half strength MS medium alone or supplemented with auxin and cytokinin induced direct somatic embryogenesis. The best response was observed in protocorms cultured half strength MS medium supplemented with BAP at 1.0mg/L and 2-4,D at 2.0mg/L. Both epidermal and sub epidermal cells were involved in the formation of embryos. The pro-embryos developed into globular stage and subsequently developed into protocoms. Complete plantlets were formed after 60 days culture. The plantlets were acclimatized in plastic pots containing sterilized vermiculite. Survival rate was 90% when maintained in culture room condition (25±2°C).

DEVELOPMENT OF AN EMBRYOGENIC SUSPENSION CULTURE IN CUCUMIS MELO

Efficient somatic embryogenesis simplifies proliferation and gene transformation of many plants. A system for induction of direct somatic embryogenesis via suspension cultures in an Iranian melon cultivar (Khatooni) was optimized. Somatic embryos were induced from quiescent seed cotyledons on liquid MS basal medium supplemented with some osmotic materials. Effect of PEG 6000, PEG 4000, glucose and sucrose were evaluated on induction of somatic embryos. The excised cotyledons were cultured in liquid media and cultures were placed on a gyratory shaker (115 rpm) for two weeks and then crossed through 50 μM metal mesh. The caught embryos were eventually moved on a solid MS medium for further growth and maturation. The number of induced embryos was significantly different in various osmotic materials. The best result was obtained from medium supplemented with 60 g/L PEG 6000. A large number of cotyledonary somatic embryos (approximately 100 embryos from each explant) were produced in this treatment while the number of embryos in glucose and sucrose treatments was less than 30 for each explant. Using the PEG, suggested a quick and efficient way for direct induction of somatic embryogenesis in melon.

High frequency shoot organogenesis and somatic embryogenesis in juvenile and adult tissues of seabuckthorn (Hippophae rhamnoides L.)

Seabuckthorn (Hippophae rhamnoides) is a multipurpose small tree with unique berries of high nutritional and pharmaceutical values. A clonally propagated plant originating from a 20-year-old tree of H. r. rhamnoides × mongolica hybrid cultivar Julia and seedling offspring of this cultivar were investigated regarding induction of shoot organogenesis in leaf explants and in roots of intact seedlings, and induction of direct somatic embryogenesis in explants from shoot tissue. The highest percentage of leaf explants showing shoot organogenesis was achieved (juvenile explants, 65%; adult explants, 75%) when incubated in Murashige and Skoog (MS) medium supplemented with either 4.5 μM of the phenylurea cytokinin thidiazuron (TDZ) or 2.25 μM TDZ plus 2.2 μM 6-benzyladenine (BA), for juvenile and adult explants, respectively, both supplemented with 0.53 μM α-naphthaleneacetic acid (NAA). Juvenile explants developed on average 18 shoots per explant in the MS medium supplemented with 4.5 μM TDZ, a four fold increase over those incubated on the medium supplemented with 2.25 μM TDZ and 2.2 μM BA. Adult leaf explants grown on medium containing 2.25 μM TDZ and 2.2 μM BA medium produced 12 shoots per explant, while those grown on medium containing 4.5 μM TDZ produced 5 shoots per explant. Shoot organogenesis was observed in roots of intact seedlings pre-cultured on plain medium lacking nutrients (PM) or woody plant medium (WPM) salts and then grown on WPM salts supplemented with 4.4 μM BA, 0.29 μM gibberrelic acid (GA3), and 57.0 μM indoleacetic acid (IAA). The number of shoots formed on each seedling root system was ten fold higher when the pre-culture was in WPM medium indicating a promoting effect of mineral nutrients in the pre-culture medium. Somatic embryogenesis was induced in both juvenile and adult leaf explants in 65 and 78% of the explants, respectively, in MS-based medium supplemented with 2.0 μM N-(2-Chloro-4-pyridyl)-N1-phenylurea (CPPU), 0.53 μM NAA and varying concentrations of BA. There was an interaction effect between MS salt strength and BA concentration. The most effective medium for inducing somatic embryogenesis in juvenile explants contained half strength MS salts and 2.2 μM BA and full strength MS salts and 13.2 μM BA for adult explants.

In vitro Propagation of Lilium longiflorum Var. Ceb-Dazzle Through Direct Somatic Embryogenesis

Experiments were carried out to investigate the effects of various concentrations of Picloram (0, 1, 2, 3, 6 and 9 mg L(-1)), TDZ (0, 0.5, 1, 1.5 and 2 mg L(-1)), NAA (1.5 mg L(-1)) in combination with TDZ (0.08, 0.2 and 0.4 mg L(-1)), 2,4-D (2.5, 5 and 10 mg L(-1)) combined with BAP (0.25 mg L(-1)) and different types of explants (basal, central and distal part of the bulb scale) on direct somatic embryogenesis induction of Lilium longiflorum var. Ceb-Dazzle. The explants were surface sterilized and cultured on MS medium supplemented with 3% sucrose, 0.3% Phytagel and various concentrations of mentioned growth regulators. It was found that Picloram at a concentration of 2 mg L-' was the most effective treatment for induction of direct somatic embryogenesis and gave the highest number of embryos (18.6) on each explant. The explants from basal part of the bulb scale showed the best responses (19.9 embryos/explant). TDZ alone or combined with NAA in various concentrations was not able to induce somatic embryogenesis, but gave direct bulblet regeneration. Similar results were obtained for 2, 4-D and BAP combination treatments. Induced somatic embryos were transferred to MS medium without growth regulators for maturation and matured plantlets were successfully acclimatized and transferred to in vivo conditions.

Plant regeneration through direct somatic embryogenesis from leaf explants of Dendrobium

A protocol for induction of direct somatic embryogenesis, secondary embryogenesis and plant regeneration of Dendrobium cv. Chiengmai Pink was developed. Thidiazuron (TDZ) at 0.3, 1 and 3 mg dm-3 induced 5-25 % of leaf tip segments of in vitro grown plants to directly form embryos after 60 d of culture, and 1 mg dm-3 TDZ was the best treatment. Somatic embryos mostly formed from leaf surfaces near cut ends, and occasionally found on leaf tips. Higher frequency of embryogenesis was obtained in light than in darkness. During subculture, secondary embryos developed from outer cell layers of primary embryos. All combinations of NAA (0, 0.1, 1 mg dm-3) and TDZ (0, 0.3, 1, 3 mg dm-3) increased the multiplication rate of embryos. It takes about 8 months from embryo induction, plantlet formation to eventually acclimatization in greenhouse.

Efficient plant regeneration through direct somatic embryogenesis from leaf explants of Phalaenopsis ‘Little Steve’

Leaf segments of the orchid sp. Phalaenopsis ‘Little Steve’ were used as explants testing the effects of 2,4-dichlorophenoxyacetic acid (2,4-D; 0.45, 2.26, 4.52 μM), 6-furfurylaminopurine (kinetin; 2.32, 4.65, 13.95 μM), N6-benzyladenine (BA; 2.22, 4.44, 13.32 μM), and 1-phenyl-3-(1,2,3-thiadiazol-5-yl)-urea (TDZ; 2.27, 4.54, 13.62μM) on the induction of direct somatic embryogenesis. After 20–30 d of culture in darkness, clusters of somatic embryos formed from leaf surfaces and wounded regions of explants on half-strength Murashige and Skoog medium supplemented with BA and TDZ. However, kinetin had no response on direct embryo induction. In addition, 2,4-D highly retarded the frequency of embryogenesis that was induced by TDZ. Generally, adaxial surfaces near wounded regions had the highest embryogenic competency compared to other regions of explants. Histological sections revealed that somatic embryos mostly arose from epidermal cell layers of the explants. Secondary embryogenesis occurred at basal parts of embryos, and originated from outer cell layers. Following transfer of regenerated embryos onto growth regulator-free medium for 3.5–4 mo., plantlets with three to four leaves and several roots were obtained. This protocol provides a simple way to regenerate plants through direct somatic embryogenesis, and is suitable for further studies on embryo development and genetic transformation of Phalaenopsis.

TIBA affects the induction of direct somatic embryogenesis from leaf explants of Oncidium

To study the effect of auxin on direct somatic embryogenesis from leaf cultures ofOncidium `Gower Ramsey', 1-cm-long explants have been cultured in vitro testing IAA, 2,4-, quercetin, TIBA and PCIB. On a modified MS medium devoid of plant growth regulators, leaf cells of three regions (leaf tips, adaxial sides and cut ends) formed somatic embryos. After 8 weeks in culture, the frequencies of embryo-forming explants were 55, 52.5 and 30 % on leaf tips, adaxial sides and cut ends, respectively, and the numbers of embryos per dish was 89.3. Except for TIBA, other growth regulators (IAA, 2,4-, quercetin, PCIB) and their combinations tested, all retarded direct embryo formation. In the presence of 0.1 and 0.5 μM TIBA, leaf tip, adaxial sides and cuts end of explants gave almost the same embryogenic response as the control. However, 10 and 27.5 % of explants were induced to form embryos from abaxial sides, and these explants did not form embryos on cut ends. In addition, after 8 weeks in culture, TIBA at 0.5 μM highly promoted the mean numbers of embryos per dish to 134.2.

A novel method to induce direct somatic embryogenesis, secondary embryogenesis and regeneration of fertile green cereal plants

A direct somatic embryogenesis and secondary embryogenesis protocol was developed for seven cereal species, thus providing a new vista for in vitro plant genetic transformation or propagation. This paper describes a novel process that has been successfully developed for efficient regeneration of a wide range of cereal species and genotypes. This tissue culture and regeneration system does not require formation of callus tissues and takes approximately 2 months to complete, shorter than any of the currently available systems requiring 3-4 months. Rapid induction of direct somatic embryogenesis in barley (Hordeum vulgare), common wheat (Triticum aestivum), durum wheat (T. durum) and derived amphiploids, wild wheat (T. monococcum and T. urartu), rye (Secale cereale) and oats (Avena sativa) was induced from excised immature scutellum on DSEM medium. Newly developed globular embryos were cultured on SEM medium for a second cycle of embryogenesis followed by germination (GEM medium) and regeneration of embryos into normally growing green and fertile plants. In vitro techniques to induce direct somatic embryogenesis, secondary embryogenesis and plant regeneration from these cereals require a specific sequence of defined media and controlled environments. The sequence and the timing of the media used, as well as their hormonal composition and balance are critical aspects of this process. The organic and mineral compositions of these media are not new but are important for supporting and sustaining rapid growth of the tissues.

The Effects of Casein and Its Constituents on the Development of Tissue Culture and Somatic Embryogenesis from Malva silvestris L.: A Preliminary Study

SUMMARY We investigated the kinetics of common mallow (Malva silvestris L.) petiole tissue growth and development in vitro, focusing on somatic embryo development at different concentrations of casein (0, 100, 200, 500 mg L−1). The results indicated the key role of casein (100–200 mg L−1) and potassium in the induction of direct somatic embryogenesis combined with a culture duration greater than 10 days. They also provided important information concerning morphogenic, physiological and biochemical aspects in addition to structural and developmental patterns in somatic embryogenesis from this still under-exploited medicinal plant species.