Callus Initiation Research Articles

Establishment of sorghum cell suspension culture system for proteomics studies

This study describes the establishment of sorghum cell suspension culture system for use in proteomics studies. Friable sorghum callus was initiated from young shoots under completely dark conditions on MS medium supplemented with 3 mg/L 2, 4-dichlorophenoxyacetic acid (2, 4-D) and 2.5 mg/L 1-naphthaleneacetic acid (NAA). Additionally, sorghum cell suspension cultures have been initiated from the friable callus masses in liquid medium with the same composition as the callus initiation medium. Total soluble proteins (TSP) and culture filtrate (CF) proteins were extracted from the cell culture system and solubilised in urea buffer (9 M urea, 2 M thiourea and 4% CHAPS). Both onedimensional (1D) and two-dimensional (2D) gel analysis of these two proteomes show that the TSP and CF proteomes have different protein expression profiles. The sorghum TSP proteome, which is highly complex, is best resolved when separated on large format, 18 cm, pH 4 - 7 isoelectric focusing (IEF) immobilised pH gradient (IPG) strips. On the other hand, the sorghum CF proteome (secretome) is less complex with most proteins being resolved on mini format, 7 cm, pH 3 - 10 IPG strips. Furthermore, narrowing down the pH range from 3 - 10 to 4 - 7 for the CF proteome resulted in improved protein spot resolution.

Effects of Growth Regulators and Explant-Type on Agrobacterium-Mediated Transformation in Brinjal (Solanum melongena L.) cv. Manjarigota

Effects of growth regulators and type of explants on transformation and in vitro morphogenetic responses of brinjal cv. Manjarigota were studied. Both hypocotyl and cotyledonary explants showed marked influence on in vitro morphogenetic responses after Agrobacterium co-cultivation. Hypocotyl explants showed callus initiation and regeneration responses earlier than cotyledonary leaves. Hypocotyl explants were found to be better than cotyledonary leaf explants in regenerating shoots after Agrobacterium co-cultivation. There was delay and reduction in both callus and regeneration responses in Agrobacterium co-cultivated explants. Hypocotyl explants showed the highest regeneration response on MS medium containing 2 μM BAP and 0.05 μM NAA while cotyledonary leaves did not show regeneration response after Agrobacterium co-cultivation. However, they showed green buds on MS medium containing 10 μM BAP and 1 μM NAA, which could not differentiate into shoots. Overall, hypocotyl explants were found better in regenerating shoots after Agrobacterium co-cultivation.

Regeneration of zoysia grass (Zoysia matrella L. Merr.) cv. Konhee from young inflorescences and stem nodes

We have optimized conditions for efficient regeneration of the vegetatively propagated zoysia grass (Zoysia matrella L. Merr) cultivar "Konhee". Two explants, young inflorescences, and stem nodes, were used and they displayed different responses to combinations and concen- trations of plant growth regulators in callusing, embryo- genic callus formation, and regeneration. The highest callus initiation rate from young inflorescences was obtained on medium supplemented with 4.5 to 9.0 μM 2,4-dicholor- ophenoxy acetic acid (2,4-D) and 0.44 μM 6-benzyl amino purine (BA). When the BA concentration was lowered to 0.044 μM, the highest percent embryogenic callus induc- tion from young inflorescences was achieved. The highest callus initiation rate from stem nodes was obtained, when young inflorescences were cultured on MS medium supplemented with 4.5 to 9.0 μM 2,4-D, 0.44 μM BA, and 0.037 μM abscisic acid (ABA). But embryogenic callus formation from the stem node was highest in the presence of 4.5 to 9.0 μM 2,4-D, 0.044 μM BA, and 0.037 μM ABA. Addition of ABA significantly increased embryogenic callus formation from stem nodes, but not from young inflorescences. Regeneration percentage was variable in response to BA level, and inclusion of α- naphthalene acetic acid (NAA) and gibberellic acid (GA3) further increased the regeneration percentage. The highest regeneration percentages obtained from the young inflor- escences and stem nodes were 82% and 67%, respectively. This is the first report showing that plants can be regenerated from young inflorescences and stem nodes of vegetatively propagated zoysia grass.

Determination of phenolic content and antioxidant activity of extracts obtained from Rosmarinus officinalis’ calli

Rosmarinus officinalis is widely found in the lands of Aegean and Mediterranean regions of Turkey. Stem explants of very young shoots were cultured in both woody plant medium (WPM) and Murashige and Skoog (MS) media supplemented with 7g/L agar, 30g/L sucrose, and 1 and 3mg/L naphthaleneacetic acid (NAA) for callus initiation. Induced calli were subcultured 4 times with intervals of 7-10 days. MS medium supplemented with 1mg/L NAA proved to be the best medium for the production of callus (65.0%) among the samples tested. The lyophilized calli were subjected to solvent extraction. Active constituents of 8 calli extracts were analyzed by HPLC, and rosmarinic acid (RA) was determined to be the primary compound. Calli cultivated in WPM supplemented with 1mg/L NAA and extracted at 50 degrees C, yielded the highest amount of RA (34.4mg/g dry weight). Moreover, antioxidant activity of calli extracts was determined using a number of in vitro assays, including total phenol assay, DPPH radical scavenging activity (RSA), and trolox equivalent antioxidant capacity (TEAC). On the basis of the current findings, we conclude that WPM supplemented with 1mg/L NAA yields higher phenolic content as well as higher antioxidant activity.

Production of embryogenic callus from leaf explants of Camellia sinensis (L.)

An attempt was made to produce embryogenic callus from leaf explants of tea ( Camellia sinensis L ) . The sterilized field-grown leaf explants were cultured on MS media with various combinations of benzyl aminopurine (BAP) and naphthalene acetic acid (NAA) to obtain embryogenic callus. The results showed that the rates of callus initiation (72.2%) and formation (56.9%) were relatively high in the medium containing 2.0 mg/L BAP and 3.0 mg/L NAA (referred as callus medium). To study the development of embryogenic callus morphologically and histologically, in vitro leaf segments were cultured on callus medium (0.8% agar) and then transferred at the 8t h week to the same medium but solidified with 0.7% agar. Results revealed that leaf segments became slightly swollen at the cut end, subsequently whitish - yellow, friable cell masseswere produced with bursting of swollen tissues. The percentage of callus initiation was 93.8% in the 6, h week of incubation. 65.8% of explants formed callus covering about half the surface of leaf segment in the 8l b week. Cy tological examination showed the development of collenchyma cells which were packed within the swollen tissues, and after bursting, parenchyma cells formed gradually as a result of cell division. These parenchyma cells de-differentiated into meristematic and embryogenic cells. A few somatic embryos (3.3%) developed from primary calli (16 weeks after incubation of leaf explants) in the preliminary study. The average number of single embryogenic cells was significantly more in liquid medium than in solid. The protocol developed in this study, will be used to obtain embryogenic callus from leaf explants and also genetic transformation. Keywords: embryogenic callus, in vitro culture,leaves, somatic embryos, tea. Normal 0 false false false MicrosoftInternetExplorer4 J. Natn.Sci.Foundation Sri Lanka 200735(3): 191-196 doi:10.4038/jnsfsr.v35i3.2018

In vitro mass propagation and greenhouse establishment of Munronia pinnata (Wall) Theob. (Binkohomba)

Munronia pinnata (Wall). Theob is a valuable medicinal plant which is widely used in Ayurvedic medicine in Sri Lanka. Due to over exploitation and low percentage of seed germination of M. pinnata it has become necessary to adopt ex situ conservation methods via in vitro propagation techniques. The objectives of this study was mass propagation, greenhouse establishment and comparison of in vitro propagated plants with seed raised plants. Callus cultures were initiated from different explant types such as apical buds, nodal segments, petioles, petals and leaf discs in Murashige and Skoog (MS) medium supplemented with 1.1 mg L 1 2,4- dichlorophenoxy acetic acid (2,4-D) and 0.5 mg L 1 benzyl amino purine (BAP) at 25 ± 1°C in complete darkness. Leaf discs (6.0 mm) showed significantly higher calli production (mean fresh weight 0.167} 0.04 g) than other tested explants. The best growth regulator combination for callus initiation was 1.1 mg L12,4-D and 0.3 mg L1 BAP which produced a mean of 0.30 ± 0.06 g callus while other treatments produced lesser amount of callus. Leaf discs taken from first fully opened leafs, produced the highest amount of callus (0.06 ± 0.01 g) and a decreasing trend was observed with increased maturity of the leaf. Tissues along the midrib area have a higher potential to give high yield of callus. Shoot proliferation was higher (32.9 /* Style Definitions */ ± 2.2) in MS medium containing 3.0 mg L 1 naphthalene acetic acid (NAA) and 3.0 mg L 1 BAP. Light intensity at 3000 lx showed significantly higher number of shoots (33.4 /* Style Definitions */ ± 2.84) than other tested light intensities. Half MS minerals supplemented with 0.2 mg L1 indole acetic acid (IAA) was the most effective treatment for root induction (75%) with the highest mean root length (15.05 /* Style Definitions */ ± 0.5 mm) and 3.15 ± 0.03 of mean number of roots. A suitable potting mixture for acclimatizationwas determined using different ratios of compost and sand. Higher percentage of survival (60%) was achieved with compost: sand 1:3. When morphological features of seed raised plants were - compared with tissue cultured plants, mean height increment was higher in seed raised plants while mean number of leaves was higher in tissue cultured plants and branching habit was observed only in tissue cultured plants. A comparison of physiological parameters between the two types of plants showed that the rate of photosynthesis was higher in tissue cultured plants whereas stomatal resistance was higher in seed raised plants. Keywords: Cold treatment, commodity treatments, de-topping, hormonal regulation, shoot morphology. Normal 0 false false false MicrosoftInternetExplorer4 J. Natn.Sci.Foundation Sri Lanka 200735(3): 181-189 doi:10.4038/jnsfsr.v35i3.2017

Effect of some Galacones and Traazolate derivatives in the development, growth and differentiation of lettuce plant Lactuca sativa .L

The effect of interaction between chalcone and triazoles on callus initiation, growth and differentiation were carried out . The results indicates that the addition of triazole compound (A) with chalcone derivatives type B or C or D to the growth medium at cone. 1 o-8 Molar enhanced callus initiation , shoot and root formation . Furthermore addition of compound A with compound C at cone. 1o-8M stimuluse callus growth compared with other compound used. It is found that the addition of chalcones and triazoles replace the standard growth regulators ( auxins and cytokinin )

Streptomyces turgidiscabies Possesses a Functional Cytokinin Biosynthetic Pathway and Produces Leafy Galls

Streptomyces turgidiscabies, a cause of potato scab, possesses a mobilizable pathogenicity island containing multiple virulence genes and a cytokinin biosynthetic pathway. These biosynthetic genes are homologous and collinear with the fas operon in Rhodococcus fascians. Reverse-transcriptase polymerase chain reaction of S. turgidiscabies demonstrated that all six genes were transcribed in oat bran broth with and without glucose, though transcription was partially repressed by glucose. The supernatant of S. turgidiscabies cultures had cytokinin activity in callus initiation and differentiation assays. Arabidopsis and tobacco plants inoculated with a thaxtomin-deficient mutant (deltanos) produced leafy galls, indistinguishable from those produced by R. fascians. Deletion of the ipt gene in the pathway eliminated gall phenotype. Other symptoms on tobacco included production of hairy roots and de novo meristems.

Effect of Antibiotics and Gelling Agents in Transformation of Brinjal (Solanum melongena L.) cv. Manjarigota

A study was conducted to find out the effect of antibiotics and gelling agents on Agrobacterium-mediated transformation using hypocotyl explants of brinjal cv. Manjarigota. Hypocotyl explants of brinjal were found to be sensitive even to the lowest level of kanamycin (25 mg/l) tested. Explants that showed increased callus initiation and regeneration response upon cocultivation with Agrobacterium and on kanamycin at 100 mg/l were selected as this indicated a highly effective selection pressure. Cefotaxime did not affect regeneration response and at 500 mg/l, it effectively inhibited Agrobacterium overgrowth completely on Agrobacterium cocultivated hypocotyl explants. There were marked differences in regeneration response in hypocotyl explants cultured on medium solidified with various gelling agents indicating the influence of gelling agent on the activity of kanamycin in culture medium, which indirectly affects selection and recovery of transformants. Antibiotics and gelling agents could therefore affect, directly or indirectly, transformation of brinjal cv. Manjarigota.

FORMATION OF Tagetes patula L. PLANTS BY TISSUE CULTURE

The present study succeeded in the initiation of callus from different explants of axenic Tagetes patula Marigold seedlings using Murashige and Skoog medium MS supplemented with 5 mg/L benzyladenine BA and 0.5 mg/l naphthalene acetic acid NAA or with 0.05 mg/L 2,4-dichlorophenoxy acetic acid 2,4-D alone or together with indole acetic acid IAA 5 mg/l. The results confirmed the differentiation capability of callus to produce plants in agar solidified MS medium containing 5 mg/L of BA and IAA. Cotyledons and leaf callus exhibited their spontaneous formation of intact plants in one step. Also Tagetes plants were produced from differentiated of other cultures of cotyledons and leaf callus in agar solidified MS medium containing 10 mg/L of gibberellic acid GA3 and 3 mg/L of IAA with 5 mg/L of BA. The produced plants were readily rooted, and subsequently were adapted to the environmental conditions through transplanting them in soil. These plants showed Somaclonal variations including plants height, number of leaves, branching system with reduction of flower size and their pedicle length as well as number of seeds, but flowers kept their red color.

Effects of hygromycin on cotton cultures and its application in Agrobacterium-mediated cotton transformation

We have evaluated the effects of the antibiotic hygromycin B on cotton (Gossypium hirsutum L.) callus induction, callus proliferation, and seed germination. Nontransgenic cotyledon and hypocotyl showed obvious variance in tolerance to hygromycin. Cotyledons were more sensitive to hygromycin than hypocotyls. Hygromycin at 7.5 and 20 mg l−1 completely inhibited callus initiation from cotyledon and hypocotyl explants, respectively. Nontransformed calli did not grow on media supplemented with 10 mg l−1 hygromycin and were killed at 15 mg l−1. In seed germination assay, the presence of 20 mg l−1 hygromycin significantly suppressed shoot and root elongation of seedlings. This hygromycin concentration was applied to select regenerated transgenic plantlets and their progenies. Based on these results, we developed an efficient hygromycin selection protocol for Agrobacterium-mediated cotton transformation and regeneration.

Protein synthesis during somatic embryogenesis of moon orchid Phalaenopsis amabilis (L.) Bl.

Research to analyse protein synthesis during somatic embryogenesis of moon orchid Phalaenopsis amabilis (L.) Bl has been carried out. One year old of plantlets were used as explants sources. Basal leaf of these explants were cultured in medium New Phalaenopsis (NP) added with 2mg/L NAA during 1 day (P1), 2 days (P2), 4 days (P3), 6 days (P4), 8 days (P5). The explants were cultured in medium NP without NAA were used as control, during 1 day (K1), 2 days (K2), 4 days (K3), 6 days (K4), 8 days (K5). Analysis of the protein synthesiswas observed by electrophoresis using SDS-PAGE method according to Maniatis et al. (1982). The measuring of protein bands used the densitometer. To detect the specific protein which possible function in controlling embryogenesis by comparing profiles of leaf protein which cultured at NP media added NAA and without NAA. The analyses of protein profile were done at the culture of day 1, 2, 4, 6 and 8 after inoculating. Result of the research indicated that a protein of 14 kDa was detected in the explants were cultured in medium NP added NAA only, and it was not detected in explants were cultured in medium NP without NAA. This protein probably embryonic protein has a function to control embryogenic callus initiation. A protein of 16 kDa was detected in the explants were cultured in medium NP added NAA and without NAA. This protein is possibly siklin has a function to regulation of cells proliferation during embryogenesis.© 2007 Jurusan Biologi FMIPA UNS SurakartaKey words: Phalaenopsis amabilis (L.) Bl, protein synthesis, SDS-PAGE

IN VITRO CALLUS INITIATION OF GUAVA

Guava (Psidium guajava L.) is an important tropical fruit rich in vitamins and vitamin precursors, minerals, organic acids, and pectins. Seventy-nine phytochemicals provide guava with many unique properties and actions including anti-microbial, astringent, bactericidal, cicatrizant, emmenagogue, hypoglycemic, laxative, nutritive, and spasmolytic. The research goal was to develop an efficient in vitro callus regeneration protocol for guava. This study evaluated specific culture media and plant growth regulators for their influences on callus initiation and production. Different concentrations of 2,4-dichlorophenoxyacetic acid (2,4-D), or 6-benzyladenine (BA) were added to Murashige and Skoog (MS, 1962) and woody plant media (WPM, Lloyd and McCown, 1981). MS culture medium strength and guava cultivars were also investigated. 2,4-D at 1.6 mg/L stimulated the most callus production for the test cultivar, 'Beaumont', regardless of the basal culture medium. The amount of callus produced per explant was significantly different among the seven test cultivars. Higher concentration (2x) of MS salts stimulated callus production.

The growth and reserpine content of callus culture of Rauvolfia verticillata on the variation of sucrose concentration in MS medium

Irmawati, Solichatun, Anggarwulan E. 2007. The growth and reserpine content of callus culture of Rauvolfia verticillata on the variation of sucrose concentration in MS medium. Biofarmasi 5: 38-46. The aim of this research was to study the effect of the variation of sucrose concentration on the growth and reserpine content on callus culture of Rauvolfia verticillata (Lour.) Baillon. The research was conducted with callus culture method consisted of two stages. The first stage was callus initiation to induce callus from leaf explant of R. verticillata, and the second stage was the reserpine production on treatment medium. This research used a Completely Randomized Design (CRD) by one factor, i.e. the variation of sucrose concentration. The sucrose concentration consisted of five levels, i.e. 0 g/L, 10 g/L, 20 g/L, 30 g/L and 40 g/L, each concentration in five replicates. The collected data consisted of qualitative and quantitative data. The qualitative data, callus morphology, was presented descriptively. The quantitative data, included fresh weight callus, dry weight callus and reserpine content, were analyzed by using ANOVA and followed by DMRT at 5% significance level. The result of research showed that the variation of sucrose concentration influenced fresh weight callus, dry weight callus and reserpine content. The increasing of sucrose concentration tended to raise callus growth, which could be seen from the fresh and dry weight callus. The highest fresh weight callus was found in medium with sucrose concentration of 20 g/L, while the highest dry weight callus was found in medium with sucrose concentration of 40 g/L. The increasing of sucrose concentration until 30 g/L raised reserpine content, but the sucrose concentration over 30 g/L decreased the reserpine content.

Plant regeneration through callus initiation from mature embryo of Triticum

AbstractThe behaviour of diverse Triticum genotypes in the tissue culture response of mature embryo callus was compared, and factors affecting tissue culture response were studied in this paper. Significant differences were detected in callus induction, embryogenic callus differentiation, plantlet regeneration and culture efficiency when mature embryos of 31 plants of different Triticum species were compared. These were the main wheat cultivars of the Chinese northern winter‐type wheat region and breeding lines (Triticum aestivum L.), durum wheat (Triticum durum Desf.), cultivable emmer wheat (Triticumdicoccum Schuble) and the common wheat progenitors Triticum dicoccoides and Triticum aegilopides. The genotype dependency was particularly high in tissue culture of mature embryos of these Triticum genotypes. The efficiency of induction, differentiation and regeneration of mature embryos callus was high in genotypes selected out. Mature embryo‐derived callus of HB341, TS021, SN2618, T. dicoccum, HB188, and T9817 showed better tissue culture response than the other genotypes. Plantlets can be regenerated from mature embryo‐derived callus of 31 genotypes, saving on growth facility resources and time required for the collection of other explants, and providing a solid basis for the genetic transformation and molecular plant breeding of Triticum plants.

Ethylene influences green plant regeneration from barley callus

The plant hormone ethylene is involved in numerous plant processes including in vitro growth and regeneration. Manipulating ethylene in vitro may be useful for increasing plant regeneration from cultured cells. As part of ongoing efforts to improve plant regeneration from barley (Hordeum vulgare L.), we investigated ethylene emanation using our improved system and investigated methods of manipulating ethylene to increase regeneration. In vitro assays of regeneration from six cultivars, involving 10 weeks of callus initiation and proliferation followed by 8 weeks of plant regeneration, showed a correlation between regeneration and ethylene production: ethylene production was highest from 'Golden Promise', the best regenerator, and lowest from 'Morex' and 'DH-20', the poorest regenerators. Increasing ethylene production by addition of 1-aminocyclopropane 1-carboxylic acid (ACC) during weeks 8-10 increased regeneration from Morex. In contrast, adding ACC to Golden Promise cultures during any of the tissue culture steps reduced regeneration, suggesting that Golden Promise may produce more ethylene than needed for maximum regeneration rates. Blocking ethylene action with silver nitrate during weeks 5-10 almost doubled the regeneration from Morex and increased the Golden Promise regeneration 1.5-fold. Silver nitrate treatment of Golden Promise cultures during weeks 8-14 more than doubled the green plant regeneration. These results indicate that differential ethylene production is related to regeneration in the improved barley tissue culture system. Specific manipulations of ethylene were identified that can be used to increase the green plant regeneration from barley cultivars. The timing of ethylene action appears to be critical for maximum regeneration.

Plant Regeneration from Immature Inflorescence Culture and Genetic Transformation of Wheatgrass ( Agropyron cristatum × A. desertorum cv. Hycrest-Mengnong)

The plants of hybrid wheatgrass ( A. cristatum × A. desertorum cv. Hycrest-Mengnong) were directly induced from embryogenic callus regenerated from immature inflorescence. Immature inflorescence was cultured on improved MS medium containing 2.0-3.0 mg L −1 2,4-D to regenerate callus. The calli were then transferred to hormone-free MS medium for differentiation and 1/2 MS medium for rooting. Results showed that callus initiation frequency was 83.4% and plant regeneration frequency was 59.6%. Phosphinothricin acetyltransferase ( bar) gene was transformed into the hybrid wheatgrass by particle bombardment. Resistant callus was obtained using selecting agent, herbicide glufosinate of 0.5 mg L −1, and some transgenic plants were recovered in vitro. The transgenic plants were identified by PCR and Southern blot analysis and these plants developed normally in the glufosinate medium, whereas the nontransgenic plants did not. The results demonstrated that bar cDNA integrated into the genomic DNA of the transgenic plants. The transgenic frequencies of bar gene were 1.1%.

(227) Guava Callus Production In Vitro

This research was initiated to study different culture media and plant growth regulators for their influences on callus initiation and production, with a research goal of developing an efficient in vitro callus regeneration protocol for guava (Psidium guajava L.). Guava is an important tropical fruit species that is rich in vitamins and vitamin precursors, minerals, organic acids, and pectins. Seventy-nine phytochemicals provide guava with many unique properties and actions, including anti-microbial, astringent, bactericidal, cicatrizant, emmenagogue, hypoglycemic, laxative, nutritive, and spasmolytic. Different concentrations of various plant growth regulators (PGR), such as 6-benzyladenine (BA), kinetin, or 2,4-dichlorophenoxyacetic acid (2,4-D), and naphthaleneacetic acid (NAA) were added to basic Murashige and Skoog (MS) and woody plant medium (WPM) and tested for their influences. Differences in callus initiation and morphology were noticed between MS and WPM, and among PGR concentration treatments.

Priming abiotic factors for optimal hybrid Cymbidium (Orchidaceae) PLB and callus induction, plantlet formation, and their subsequent cytogenetic stability analysis

Abstract Abiotic factors affect the induction of PLBs and callus in hybrid Cymbidium Twilight Moon ‘Day Light’. The initiation and proliferation of new PLBs and callus could be achieved on NAA and kinetin, supplemented at 0.1 mg l −1 each, respectively, both within 45–60 days. Bacto agar was found to be the most suitable solidifying agent for PLB induction, although a higher shoot fresh weight was obtained on Gelrite; a pH 5.3 was optimal while pH 4.5 caused 100% explant necrosis; coconut water, when supplied at 10–20% (v/v) resulted in a significant increase in the number of PLBs formed per PLB segment (23.1 versus 14.6 in controls) while a massive (almost four-fold) increase in fresh top weight occurred when PLB explants were placed in liquid culture, as a result of hyperhydricity; Fe-EDTA (1 mg l −1 ) and activated charcoal (1 g l −1 ) stimulated total fresh weight and PLB formation in the presence of PGRs; PLB formation decreased but total fresh shoot weight increased with the addition of niacin or myo -inositol, both vitamins. Dark-grown PLB-induced plants were etiolated and had longer internodes and higher fresh weight than light-grown control plants at 45 μmol m −2 s −1 ; at 15 μmol m −2 s −1 shoots were slightly etiolated, fragile, and PLB formation was scarce. RAPD and mtDNA analysis of all resultant PLBs, callus or plants showed them to be genetically identical, with comparable chlorophyll contents. Despite the detection of cytological variation between different plant parts, little variation resulted from abiotic factor treatment.

Somatic Embryogenesis Formation from Immature Male Flower of Banana cv. Nangka

The plantain banana (cultivar nangka) is among the most valued crop plants in the tropical world. However, the commercially attainable yields are very low compared to other food crops. Somatic embryogenesis has the great potential for rapid and efficient regeneration of plantlets and offers opportunities for large-scale production of plant material. Genetic modification on embryogenic structure offers the opportunity to add desirable gene characteristic. The objective of this study was to evaluate the different medium combination for the induction and optimization of embryogenic formation from immature male flowers. The explants of inflorescence was sampled one month after bunch emergence and approximately 15-20 cm below the last female flower hand. Response of explants and percentage of inflorescence clusters forming nodular callus were recorded and noted. Result of the experiment showed that embryogenic callus could be induced from immature male flowers. The initiation of callus indicated of flower cluster responded to form globular embryogenic callus (49.7% ± 5.2), whereas the percentage of flower cluster responding to form nodular callus was 39.2 % ± 5.3. The highest response of explants forming nodular callus was from flower of rows 12 and 13 (60%).