Meristem culture and micropropagation of a variety of ginger (Zingiber officinale Rosc.) with a high yield of oleoresin

Summary

Meristems of ginger with or without leaf primordia were induced to form shoots on three-quarter strength Murashige-Skoog’s (MS) medium containing sucrose 6%, coconut milk (CM) 20%, ascorbic acid (AA) 100 mg l^?1, glutamine (GL) 400 mg l^?1, activated charcoal (AC) 250 mg l^?1, 6-benzylaminopurine (BAP) 0.5 mg l^?1, indolebutyric acid (IBA) 0.4 mg l^?1 and agar 0.8%. Meristem-derived shoots exhibited consistent multiplication on three-quarter strength MS medium containing sucrose (3%), AA (100 mg l^?1), AC (100 mg l^?1), BAP (4–5 mg l^?1) and agar (0.8%). Liquid media (agitated or static) were less effective than a solid (agar-gelled) medium for micropropagation. Kinetin and naphthalene acetic acid (NAA) incorporated at various levels (0.01–0.8 mg l^?1) with or without added BAP and IBA neither improved plantlet formation nor enhanced shoot multiplication. The in vitro plants were successfully established in vivo and the rhizome yield was comparable with that of plants grown by conventional methods.     

Micropropagation of guava (Psidium guajava L.)

Summary

Guava (Psidium guajava L.) is difficult to propagate using conventional asexual techniques, with most growers using seedling planting stock. However, these seedlings are highly variable. We therefore developed an in vitro technique to clonally propagate guava. Various concentrations of BAP (6-benzylaminopurine) and TDZ (thidiazuron) were used to regenerate and micropropagate plants. Two explant sources were compared: greenhouse grown plants (GHRP) and in vitro-harvested axillary buds (IVDS). GHRP with BAP at 2 mg l^–1 gave 3.7 shoots per single node cutting with an average length of 0.7 cm. Shoots 3.0 cm long were obtained with 0.5 mg l^–1 BAP, however only 2.1 shoots per explant were produced. For IVDS, the largest number of shoots (3.9 per explant) was obtained with BAP at 0.25 mg l–1 , with an average shoot length of 1.6 cm. Generally, lower concentrations of BAP gave fewer but longer shoots. The highest number of roots and longest roots per shoot (5.4 and 2.0 cm, respectively) were obtained with 1 mg l^–1 indole-3-butyric acid (IBA). A protocol for producing clonal plants over eight weeks is described.     

In vitro propagation of ‘Troyer’ citrange from epicotyl segments

Isolated epicotyl, root meristem and root segment tissues of ‘Troyer’ citrange [Poncirus trifoliata (L.) Rat. × Citrus sinensis (L.) Osbeck] were established in continuous culture to compare their regeneration potential. Callus was obtained from these explants on a Murashige—Skoog (MS) medium containing NAA (10 mg l^?1) and BAP (0.1–10 mg l^?1). Formation of shoots from root segments was direct without callus formation on MS medium containing BAP (10 mg l^?1) and NAA (1 mg l^?1). Shoot formation from epicotyl callus occurred on MS medium containing 0.25 mg l^?1 BAP and 0.1 mg l^?1 NAA. Formation of shoots from epicotyl segments occurred on MS medium containing BAP (0.5 mg l^?1) and NAA (0.1–1.0 mg l^?1), while rooting of regenerated shoots occurred in treatments containing 2.0 mg l^?1 NAA alone. This system provides a rapid method for propagation of ‘Troyer’ citrange.     

The Influence of Some Genetic and Environmental Factors on the Concentration of L-Ascorbic Acid in the Tomato Fruit

Summary

An efficient, reproducible protocol has been developed for in vitro multiplication of Sida cordifolia L. High-frequency, multiple shoots (90%) were obtained indirectly from nodal explants. Callus was induced when nodal explants were cultured on Murashige and Skoog (MS) medium supplemented with 0.5 mg l^–1 Kinetin (Kn). These nodal calli were then cultured in order to differentiate multiple shoots on MS medium supplemented with 0.5 mg l^–1 Kn plus 0.5 mg l^–1 naphthaleneacetic acid (NAA). Roots were induced from these multiple shoots following culture on MS medium supplemented with 0.8 mg l^–1 NAA for 4 weeks. Finally, these in vitro plantlets were hardened, acclimatised, and successfully transferred to the field.     

Cost-effective tissue culture media for large-scale propagation of three commercial banana (Musa spp.) varieties

Cost-effective tissue culture protocols have been established for the commercial multiplication of three banana varieties, ‘Rasthali’ (AAB – Silk), ‘Grand Naine’ (AAA – Cavendish), and ‘Udhayam’ (ABB – Pisang Awak). Reverse osmosis water and 3% (w/v) table sugar were used as the low-cost water and carbon source, respectively. Six different gelling agent treatments were tested: sago alone (T1), Isabgol alone (T2), sago + agar (T3), Isabgol + agar (T4), sago + Isabgol (T5), and agar alone as a control (T6). Full-strength Murashige and Skoog (MS) medium supplemented with 3 mg l^–1 6-benzylaminopurine (BAP) and 1 mg l^–1 indole-3-acetic acid (IAA) were used for culture initiation and subculturing. Rooting was accomplished on low-cost MS medium containing 1.0 mg l^–1 α-napthaleneacetic acid (NAA), 1.0 mg l^–1 indole-3-butyric acid (IBA), and 250 mg l^–1 activated charcoal. Statistical analysis indicated that sago + Isabgol (T5) produced the maximum number of shoots (10 per explant) in ‘Udhayam’ and ‘Rasthali’, while sago alone (T1) produced the maximum number of shoots (6 per explant) in ‘Grand Naine’. The genetic stability of tissue-cultured banana plantlets produced using these low-cost substitutes was assessed using inter-simple sequence repeat (ISSR) markers. The results indicated that the ISSR profiles of the five treatments and the control (T6) were similar, indicating genetic stability using these cost-effective tissue culture protocols. Reductions in cost over the control (l^–1 of MS medium) ranged from 65% to 86%, while the per plant production cost was reduced by 12.5%–20.0%. Adoption of these treatments (T1–T5) as low-cost tissue culture protocols for in vitro propagation would reduce production costs significantly, leading to an expansion of the area planted with tissue-cultured banana, thereby increasing productivity.     

Development of micropropagated plants from different clones of Senecio x hybridus in relation to BAP concentration and temperature in vitro

Summary

Selected mature seedling plants were used as stock plants and about half of them were successfully micropropagated. There was no correlation between the ability of petiole expiants to form adventitious shoots and the capacity of these shoots to multiply. Growth and development varied between the micropropagated clones, originating from one seedling each. The colour of the flowers was always constant within a clone. Developmental time, foliage height and the numbers of shoots, leaves and flowers were influenced by the BAP concentration used in vitro. The temperature during the in vitro phase affected the development time and the height of foliage and inflorescences. Increased BAP concentration (from 0 or 0.1 mg l^?1 to 1 mg H) resulted in plants with a longer development time to anthesis and more shoots, leaves and flowers. Plants raised on 5 mg l^?1 BAP developed slowly, resulting in stunted growth, low foliage height, few leaves and flowers. Consequently, it is possible to use the BAP concentration in vitro to regulate the growth of the progeny crop. After transfer to soil in a growth chamber, plants grown at 10°C in vitro flowered earlier, and had lower foliage and higher inflorescences than plants grown at 21°C. This observation indicates that flowering may be promoted by low temperatures in vitro.     

Rapid micropropagation of Psoralea corylifolia L. using nodal explants cultured in organic additive-supplemented medium

Summary

The influence of different growth regulators and additives on shoot multiplication from nodal explants of Psoralea corylifolia was investigated. Prolific shoot multiplication was achieved within 4 weeks of culture on Murashige and Skoog (MS) medium supplemented with 5 μM benzyladenine (BA), 5 μM ascorbic acid (AA), 100 mg l^–1 casein hydrolysate (CH) and 5% (v/v) coconut water (CW). Shoots elongated on half-strength MS basal medium devoid of inositol, but containing 5 μM 2-isopentenyladenine (2iP), 10 g l^–1 sucrose and 8 g l^–1 agar. Elongated shoots rooted on half-strength MS basal medium supplemented with 3 μM indole-3-butyric acid (IBA), 10 g l^–1 sucrose and 7 g l^–1 agar within 5 d of culture. The in vitro-raised plants were established successfully in 2:1:1 (v/v/v) garden soil:farmyard soil:sand, and maintained in a growth chamber with 100% survival. Acclimatised plants were transferred to a glasshouse and established successfully in the field. Flowers and fruits appeared after 4 months and resembled those on source plants. This system could be used for rapid commercial propagation of P. corylifolia for conservation strategies and to produce phytomedicines.     

Regeneration of various species of Crassulaceae,with special reference to Kalanchoë

Summary

Four species of the genus Kalanchoë (Crassulaceae), K. peltata, K. laxiflora, K. tubiflora and K. marmorata, were regenerated from leaf explants by direct organogenesis. Each species was tested on 19 media, all based on MS-medium. One medium was without growth regulators, the remaining 18 contained a combination of auxin and cytokinin. Auxin was indole-3-acetic acid (IAA): 1.1, 2.3 or 4.6 μM (0.2, 0.4 or 0.8 mg l^–1). Cytokinin was either 1-phenyl-3-(1,2,3-thidiazol-5-yl)urea(TDZ): 1.1, 2.3 or 4.5 μM (0.25, 0.5 or 1.0 mg l^–1), or 6-benzylaminopurine (BAP): 1.1, 2.2 or 4.4 μM (0.25, 0.5 or 1.0 mg l^–1). For each species an optimum level of growth regulators were obtained. One medium, called K22, containing 0.5 mg l^–1 TDZ and 0.04 mg l^–1 IAA, showed good shoot-generating capacity with all four species. Shoot elongation proved to be a problem only with K. marmorata. This could be bypassed by transferring shoots to a gibberellic acid (GA₃)-containing medium, or by ventilating the containers. Shoots were rooted on MS-medium and rooted shoots were transferred to soil. K. laxiflora failed to root, but plantlets produced on the leaves were easily used for vegetable proliferation of the regenerated shoots. Eight additional Kalanchoë species and four species from other genera of Crassulaceae: Crassula, Echeveria and Sedum, were tested for regenerative capacity on K22-medium. From four Kalanchoë species and three other species, regenerated plants were established in soil. These results suggest that this medium has a high regenerative capacity within the Crassulaceae. No close dependency was found between systematic position and ability to regenerate on this medium.     

Rejuvenation influences indirect organogenesis from leaf explants of Pomegranate (Punica granatum L.) ‘Kandhari Kabuli’

Sequential subculturing leads to a gradual physiological change in cells that may be termed ‘rejuvenation’. The effect of repetitive subculturing on callus induction and shoot regeneration from leaf explants of Punica granatum L. ‘Kandhari Kabuli’ were investigated. Surface-sterilised leaves were cultured on 1.0× Murashige and Skoog (MS) medium supplemented with 4.0 mg l^–1 α-naphthaleneacetic acid (NAA) and 2.0 mg l^–1 6-benzyladenine (BA) for callus induction. Shoots were regenerated from callus on 1.0× MS medium supplemented with 1.5 mg l^–1 BA, 0.5 mg l^–1 kinetin, and 0.25 mg l^–1 NAA. Subculturing of callus onto fresh medium maintained the rate of shoot formation and substantially increased the production of shoot buds up to the second subculture. Following further subculture passages, a lower shoot regeneration potential from callus was observed. A maximum shoot bud induction from callus of 63.9% was observed at the second subculture passage. The rate of multiplication of in vitro shoots increased until the fourth subculture, then became constant. Similarly, in vitro rooting of micro-shoots increased up to the third subculture, followed by a decline during further subculturing.     

The Effect of Soil pH and Manganese Toxicity Upon the Growth and Mineral Composition of the Hop Plant

Summary

The productivity of ornamental foliage plants is related to their capacity to increase their leaf number and leaf size. In Monstera deliciosa, a change in leaf shape is also a pre-requisite for successful marketing. The aim of this work was to describe the effects of different concentrations of exogenous 6-benzylaminopurine (BAP; 5, 50, 100, or 200 mg l^–1) on the control of both leaf size and leaf shape in M. deliciosa, and the impact of these changes on commercial plant productivity. We found an increase of between 15.4 – 23.1% in the rate of leaf appearance (RLA), which reflected a shortening of the phyllochron, and an increase of between 17.5 – 34.9% in the relative rate of leaf area expansion (RLAE) at most of the BAP concentrations tested. This resulted in higher biomass accumulation in both roots and shoots through an increase of between 5.4 – 7.9% in the relative growth rate (RGR), mainly associated with higher net assimilation rates (NAR; increases from 9.0-fold to 11.0-fold) and increased photoassimilate partitioning to the shoots. The most important result of this work was the early appearance of perforated leaf laminae in M. deliciosa plants sprayed with 50 – 200 mg l^–1 BAP, which made them ready for sale.     

Influence of BAP Concentrations and Nutrient Medium Composition on <Emphasis Type="Italic">In Vitro</Emphasis> Regeneration of ‘Öküzgözü’ and ‘Boğazkere’ (<Emphasis Type="Italic">Vitis vinifera</Emphasis> L.) Cultivars

This study has been conducted with the aim to determine the type of nutrient medium that can be used in micropropagation studies for ‘Öküzgözü’ and ‘Bo?azkere’ and to specify BAP concentrations. In the study where ejectors with a length of 0.7–0.8?cm that are obtained with single-node culture are used, it was focused on four different nutrient media such as MS, DKW, QL and WPM and on six different concentrations such as 0.2–0.4–0.6–0.8–1.0–1.5 mg l^?1 BAP. Single-node suspension explants which will be used in initiating the culture, are taken into culture in MS nutrient medium and the nutrient medium is supported with 30?g l^?1 sucrose, 6?g l^?1 agar and 1?mg l^?1 BAP. In the trial environment, parameters such as number of shoots, shoot length (cm), number of nodes and callus ratio have been investigated. For both grape varieties, the best outcome was obtained with MS nutrient medium with respect to number of shoots, shoot length, and number of nodes. These values were found as 4.66, 1.24 and 6.39 for ‘Öküzgözü’ variety respectively, whereas they are determined as 6.28, 1.15 and 6.81 for ‘Bo?azkere’ variety respectively. In both grape varieties in DKW nutrient medium, starting from the 2nd week of culture, obscuration began to appear on the shoots and after this stage no other development has taken place.     

Direct regeneration of plants derived from in vitro cultured shoot tips and leaves of three Lysimachia species

The regenerability of three ornamental species—Lysimachia christinae, Lysimachia rubinervis and Lysimachia nummularia ‘Aurea’, were investigated using in vitro leaves and shoot tips. 6-Benzylaminopurine (BAP) and α-naphthalene acetic acid (NAA) added to Murashige and Skoog (MS) medium were tested for their effect on organogenesis. On the medium, shoot regeneration occurred directly without callus formation. In these species, L. christinae developed the highest regeneration rate and numbers of shoots/explant from shoot tips (100%, 12.25) and leaf bases (100%, 13.01) on the MS medium containing 3.0 mg l⁻¹ BAP and 0.1 mg l⁻¹ NAA. For L. rubinervis, the highest shoot induction rate and number of shoots/explant were obtained from shoot tip (100%, 16.87–17.20) on the MS medium with 0.1 mg l⁻¹ NAA and 3.0–5.0 mg l⁻¹ BAP. L. nummularia ‘Aurea’, however, showed the highest regeneration rate and number of shoots/explant (100%, 12.73) from leaf bases on MS medium supplemented with 1.0 mg l⁻¹ BAP and 0.1 mg l⁻¹ NAA. All in vitro shoots rooted well on half macronutrient MS medium containing 0.1 mg l⁻¹ NAA. After acclimatization, transplanted plantlets grew normally and flowered in the field.     

The use of CPPU for efficient propagation of pineapple

The use of forchlorfenuron (N-(2-chloro-4-pyridyl)-N′-phenylurea) (CPPU) for efficient propagation of pineapples was investigated. About 85% of axillary buds can be forced to sprout by soaking defoliated stem pieces (12 cm in length) in a 2.5 or 5.0 mg l⁻¹ CPPU solution for more than 3 h. The use of old stems taken from the third or fourth ratoon plants had the advantage of less liability to fungal decay, as compared to young stems from the first crop plants. The CPPU treatment combined with the removal of shoots from stems at monthly intervals significantly increased the number of shoots per stem piece (about 15 shoots per piece at 5.0 mg l⁻¹ CPPU), and resulted in a more uniform shoot size (the percentage of shoots within a range of 5–15 cm in length was about 90% at 5.0 mg l⁻¹ CPPU). The rooting of shoots was easily promoted within 1 month by treating the basal portion of shoots with 20 mg l⁻¹ indole-3-butyric acid (IBA) for 15 min. The CPPU method required about 5 months for plantlet propagation. From these results, we found that pineapple plantlets could be efficiently propagated by the following method: (1) soaking defoliated stems in a 2.5–5.0 mg l⁻¹ CPPU solution for more than 3 h; (2) harvest of developed shoots from the stems at regular intervals; and (3) promotion of rooting on the shoots at 20 mg l⁻¹ IBA for 15 min.     

Culture of triploid tissue from the endosperm of an endangered Chilean tree species Gomortega keule

The endangered Chilean tree species Gomortega keule (Mol.) Baillon produces an edible fruit, but is not cultivated at present. Recent advances in micropropagation may allow the further development of this species as a fruit crop. Triploid plants have been regenerated from the endosperm of seed of a number of species. This is the first report on in vitro culture of the seed endosperm of G. keule in order to obtain triploid plants. Callus was formed from endosperm after 1.5 months on 1.0× Murashige and Skoog medium supplemented with 2,4-dichlorophenoxyacetic acid and 6-(γ,γ-dimethylallylamino) purine. Shoot primordia developed and produced shoots that could be cultured on Rugini medium containing 0.1 mg l^–1 α-naphthaleneacetic acid and 1 mg l^–1 6-benzyladenine. Shoot primordia cultured on Rugini medium containing 2 g l^–1 activated charcoal produced longer shoots and longer leaves compared to diploid genotypes. Flow cytometry and chromosome observations indicated that the callus tissue and plantlets derived from the seed endosperm were triploid. Endosperm culture represents a feasible method to regenerate triploid plantlets of this tree species within 18 months. Such material may be of value for the genetic improvement and future development of G. keule as a commercial fruit tree species.     

Optimisation of a highly efficient shoot regeneration system using leaf explants of Chinese jujube (Ziziphus jujuba Mill.) by response surface methodology

Chinese jujube (Ziziphus jujuba Mill.) is a major fruit crop in Asia. In this study, response surface methodology (RSM) was successfully employed to establish a highly efficient in vitro propagation and regeneration system for the ‘Teapot’ jujube via shoot organogenesis. Among the tested factors, gibberellic acid (GA₃) concentration showed the most significant positive effect. The pre-culture darkness timing and medium were also important factors for highly efficient shoot regeneration of the ‘Teapot’ jujube. The highest regeneration (> 75%) was achieved by 1 week in darkness and culture on wood plant medium (WPM) containing 0.25 mg·L^?1 GA₃, 0.5 mg·L^?1 6-benzylaminopurine (BAP) and 0.1 mg·L^?1 3-indoleacetic acid (IAA). In vitro-derived shoots rooted very well in the modified ¹/₂ Murashige and Skoog (MS) medium containing 0.4 mg·L^?1 3-indolebutyric acid (IBA), resulting in a 100% rooting rate. These findings suggest that the RSM can be employed to optimise the protocols needed for successful in vitro plant regeneration of jujube cultivars, with potential applications in plant genetic transformation practices, polyploidy induction and germplasm preservation.     

Castanea sativa plantlets proliferated from axillary buds cultivated in vitro

Chestnut plants were proliferated in vitro from axillary buds of juvenile shoots. N6-Benzyl-aminopurine (BAP) at 0.1?0.5 mg l^?1 was optimal for shoot multiplication. The important role played by the macronutrient formula on shoot multiplication, and especially on the rooting-stage, is emphasized. The MS ($\text{1}\text{2}$ NO₃) macronutrients gave the best rooting percentage as well as the highest number of roots per rooted shoot. In these experiments, shoots remained in the 3 mg l^?1 indole-3-butyric acid (IBA) medium for 12 days, after which they were transferred to an auxin-free medium where roots developed fully. Optimum rooting was achieved by immersing the 1 cm basal end of shoots in concentrated IBA solutions (0.5?1 mg ml^?1) for periods ranging from 2 to 15 min.     

Direct somatic embryogenesis from explants obtained from in vitro germinated embryonic axes of Camellia sinensis (L.) O. Kuntze

Summary

Studies on direct somatic embryogenesis in several types of explant from in vitro plantlets of tea cultivar TRI 2025 were undertaken to select those most suitable to induce cotyledonary-type somatic embryos. Mature zygotic embryonic axes were surface-sterilised and cultured on MS medium without growth regulators containing 0.6% (w/v) agar. Results showed that 65% of embryonic axes that converted into plantlets at the fifth week of culture had succulent leaves. Several types of explant (normal leaves, large and small succulent leaves, hypocotyl segments and root tips) were isolated from in vitro plantlets at the fifth week and cultured on half-strength MS medium containing 2 mg l^–1 6-benzylaminopurine (BAP) and 0.2 mg l^–1 naphthalene acetic acid (NAA). Morphological and histological observations on somatic embryogenesis were made. The results indicated that somatic embryos were produced at high frequency (25 – 50%) directly from the surface of hypocotyl segments (HS) and large succulent leaves (LSL) after 6 weeks of culture. Efficient somatic embryogenesis was induced in small succulent leaves (SSL) after 16 weeks. Most somatic embryos originated directly from the cortical tissues of HS or the upper epidermal layers of SSL or LSL. HS and SSL from in vitro plantlets gave the highest production of typical, firm somatic embryos for use in tea improvement programmes and for in vitro conservation of tea germplasm.     

Molecular identification and antibiotic control of bacterial contamination in cultures of ginger (Zingiber officinale)

Zingiber officinale, Rosc., one of the major tropical spices in the world, belongs to the family Zingiberaceae. Bacterial contamination is a major constraint on the cryopreservation of in vitro shoot tip explants. The main objective of this study was to identify the nature of this bacterial contamination and its response to various antimicrobial agents (e.g. the antibiotics cephotaxime and streptomycin sulphate, or copper sulphate) for more effective control. The bacteria isolated from ginger plantlets were identified by amplification and sequencing of their 16S ribosomal DNA, followed by partial sequence analysis. Luteibacter yeojuensis was found in all contaminated cultures. L. yeojuensis is found mainly in soil and as a human pathogen. We believe this is the first report of L. yeojuensis contaminating in vitro cultures of ginger. Among the antimicrobial agents tested in the shoot multiplication medium [i.e. 1.0× Murashige and Skoog salts + 2.5 mg l^–l 6-benzylaminopurine + 3% (w/v) sucrose + 0.45% (w/v) Clarigar^TM], 100 mg l^–1 cephotaxime was most effective at reducing bacterial growth. It also gave the maximum number of shoots per shoot bud explant compared to the same medium supplemented with streptomycin sulphate, or CuSO₄, or control medium. No further bacterial contamination was observed when 8-week-old cultures were then subcultured on the same medium without added antibiotic or CuSO₄.     

Viability of excised embryos,shoot proliferation and in-vitro flowering in a species of rattan Calamus thwaitesii Becc.

Summary

92% of embryos excised from fresh mature unripe fruits of Calamus thwaitesii germinated in a modified Y3 medium with 0.05 mg l^±1 of 6-benzylaminopurine (BAP). This was higher than the 72% germination obtained with ripe seeds sown in soil. Stored seed lost viability within two weeks due to dehydration of embryos. Germination commenced with the differentiation of the haustorium and the cotyledonary sheath, observable in embryos germinating in vitro. This was followed by the development of the plumule. The first eophylls were simple and lanceloate. Decapitation of the in-vitro seedlings and transfer to a medium with higher levels of BAP at 5 or 8 mg l^±1 resulted in the production of multiple shoots after 4±5 months, initially from buds that developed around the collar region. Repeated subculture resulted in the development of a clustering habit similar to that of field clumps with a rhizome, axillary shoots and dormant buds. Two axillary meristems were induced to develop precociously into inflorescences. Incorporation of activated charcoal and alpha-naphthaleneacetic acid (NAA) with 5 or 8 mg l^±1 BAP reduced multiple shoot formation and brought about root development. Single shoots or clusters developed roots in a Y3 medium with reduced macro elements and supplemented with NAA (5.mg.l^±1) and activated charcoal. Nursery establishment with 65% survival of plantlets was possible. In-vitro culture of excised embryos could be recommended, as propagules could be made available whenever desired by rooting proliferated shoots. It also allowed the safe transport of germplasm.     

High multiplication frequency and genetic stability for commercialization of the three varieties of micropropagated tea plants (Camellia spp.)

RAPD and microsatellite markers were used to determine the genetic fidelity of micropropagated plants from the three varieties of tea plant derived from explants of field grown mother bush as well as in vitro germinated seedlings. Rate of shoot multiplication was better from nodal explants than from shoot tips. A maximum of 32–33 shoots was observed in cotyledonary node in 1/2 MS medium with BAP (6 mg/l), GA₃ (1 mg/l) and IBA (0.5 mg/l). 90% of the in vitro derived microshoots were micrografted into rootstocks. The micropropagated plantlets showed both cytological and genetical stability. SSR primers showed complete stability among the regenerants. The results convinced that plants derived from axillary as well as adventitious mode of propagation can be genetically true to type. This cost effective technique would help in fast clonal propagation at a commercial scale.