Anthurium known world wide for its beauty and variety of colours is an important tropical flower crop. Anthurium andreanum Lind. is the most popular and economically important species grown for its attractive inflorescence and is popular for their bold effect and long vase-life. Commercial cultivation of Anthurium in India is still in its infancy due to lack of elite indigenously developed varieties and standard agro-techniques. Anthurium can be propagated through seeds and through vegetative methods such as divisions, cuttings, etc. In case of seed as propagule, the time required to get a seed from seed is more than three years. The time required from pollination to the maturity of the seed is about 6–7 months and seeds cannot be stored, it should be sown immediately. Hence, seed propagation is generally followed for developing new varieties as the propagated progenies generally show variation in vegetative and floral characters that the plant breeders are generally looking for. The vegetative propagation by conventional terminal cutting and stem sections is very slow and achieves only about 8 folds (Geier, 4). Because of increased possibility of appearance of genetic changes in plant prorogated by callus culture, Kunisaki (5,6) stimulated the organogenesis of Anthurium andreanum Lind. from meristems and achieved their proliferation. This system was, however, not effective and efficient enough. Hence, for rapid multiplication of a newly developed variety for evaluation and commercial cultivation, an efficient tissue culture clonal propagation is a must to ensure ‘true to type’ nature. Also, many research workers observed that within a species there exists variation for in-vitro responses among different varieties. Therefore, an experiment was conducted at tissue culture laboratory at K.V.K., Gonikoppal, Kodagu to standardize in-vitro protocol for clonal multiplication of anthurium.

Shoot tips derived from in-vitro anthurium plants of the variety Singapore hybrid were used as explant (Fig. 1). Shoot tips of one-centimetre length with 2 leaves were excised from 8–10 months old plants cultured on MS medium supplemented with 2 mg/l of IBA and 6 mg/l of kinetin and transferred on to MS medium (Murasighe and Skoog, 7) with 3% sucrose supplemented with different concentrations of kinetin. The medium was gelled with phytagel (0.25 % Sigma Chemical Co. USA) and the pH adjusted to 5.8 prior to autoclaving at 121°C for 15 min. Culture were incubated in culture racks provided with cool white fluorescent tubular lamps with a light intensity of 30–40 m moles m^-2 s^-1 under a 16 h photoperiod in a culture room maintained at 25 ± 2°C. The proliferated shoots were cultured on half-strength MS media with 2% sucrose and various concentrations of IBA viz., 0.25, 0.5, 1.0, 1.5 and 2.0 mg/l for root induction. Observations were recorded after 10 weeks from the date of in-vitro shoot tip culture for shoot multiplication and for rooting, 6 weeks after transferring the proliferated in-vitro shoots on different rooting media. The complete plantlets obtained through in-vitro shoot proliferation after root induction were transferred on to three different hardening media viz., coffee husk, coco peat and organic manure in varying concentration of FYM (with or without), soil and sand filled in portrays. The effect of each type of hardening media on ex vitro plant establishment was observed.

Among different concentrations of kinetin tried, higher mean shoot proliferation (91.66%) was observed at 4 mg/l kinetin (Table 1, Fig. 2). Maximum mean number of shootlets (5.14) was also observed at 4 mg/l kinetin. However, the difference for mean number of shoot lets between the treatment 5 mg/l kinetin (4.69) and control (4.72) was not significant. The variation may be due to different endogenic levels of kinetin and slight variation in the growth of shoot lets used for inducing proliferation. Kunisaki (6) observed best clonal increase in Anthurium andreanum Lind. using stem sections when cultured on medium containing 6-benzyl aminopurine (BA). Geier (3) found BA is the most effective cytokinin in production of Anthurium scherzerianum shootlets compared to kinetin and zeatin. Influence of all the cytokinins used (BAP, zeatin, kinetin and 2-ip) on growth and development of single node shoot fragments of Anthurium x cultorum was reported by Soczek and Hamoel (8). It was observed that mean shoot length (2.67 cm) was higher in kinetin (4 mg/l) followed by kinetin (5 mg/l) and kinetin (6 mg/l), but the difference between these treatments for mean shoot length was non-significant. However, the treatment with kinetin (0.0 mg/l) (control) differed significantly with kinetin (4,5 and 6 mg/l) though it recorded second highest mean for number of shootlets per explant. The difference in mean shoot length between control and the best treatments may be due to the exogenic levels of growth regulator used. Further, it was observed that the maximum mean number of leaves per explant was recorded in kinetin (4 mg/l).

Among the different concentrations of IBA, maximum mean rooting (83.00%) of shootlets was observed in 1.0 mg/l (IBA) followed by 0.25 mg/l (IBA) (Table 2, Fig. 3). This difference may be due to slight variation which existed in the shoots taken for inducing rooting and the levels of growth regulator used. Eapen and Rao (2) reported best rooting of shootlets when transferred on to the media containing NAA at 1.0 mg/l. It was observed that mean number of roots was higher (8.33) in 1/2 MS (without IBA) followed by IBA (0.25 mg/l) and 0.50 mg/l. However, the difference between these treatments was not significant. The nonsignificant variation may be attributed to endogenous levels of auxins. Further, at higher concentrations of IBA, callus formation was observed at the cut ends. Mean root length recorded was highest in 1.0 mg/l (IBA). The difference between them was nonsignificant. Among all the shootlets grown on medium supplemented with different concentrations of IBA, adventitious roots were noticed which arise from leaf base attached to main stem.

The survival rate of 80 percent plantlets was achieved (Table 3) in the medium coffee cherry husk: FYM: soil: sand at 2:1:1:1 proportions (Fig. 4). Devinder Prakash et al. (1) successfully hardened plants under green house condition in a 2:1:1 mixture of coco peat, soil and farm yard manure. During rainy season, the survival rate was more than 95%. The reason may be the influence of prevailing higher humidity (80%) and temperature (28°C) of outside environment on the inside conditions of hardening chamber.

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