An in vitro regeneration system for propagation of a valuable medicinal tree, Pterocarpus marsupium, using shoot tip (ST) explants derived from 7-d-old axenic seedlings has been successfully developed. Murashige and Skoog (MS) medium containing cytokinins (BA, mT, or Kn) and auxins (NAA, IAA) in different concentrations and combinations showed to have a marked stimulatory effect on the regeneration output. Of cytokinins, meta-topolin (mT 7.0 μM) proved optimum dose for multiple shoot induction yielding 6.50 ± 0.49 shoots per explant with mean shoot length (4.00 ± 0.16 cm) in 70% cultures after 6 wk. Whereas, supplementation of low concentration of auxin (1.0 μM NAA) with optimal cytokinin (7.0 μM mT) favored enhanced shoot induction with increased percent response. At this level, a maximum of 13.54 ± 0.34 shoots per explant with (5.30 ± 0.10 cm) mean shoot length were recorded in 80% cultures after 12 wk. Thereafter, microshoots were isolated and their basal end treated with high doses of indole-3-butyric acid (250 μM) for 5 d followed to transplant onto various potting substrates for ex vitro root formation. A maximum of 3.63 ± 0.0.08 roots per microshoot and mean root length of 3.59 ± 0.07 cm with highest rooting frequency (67.7%) was observed after 4 wk of transplantation. During ex vitro rooting-cum-acclimatization, various physiological parameters were found to be fluctuating initially for 35 d; thereafter, an increasing trend was observed in net photosynthetic rate, intercellular CO₂ concentration, and chlorophyll a/b estimation. Overall, the successfully acclimatized regenerants when transferred in natural condition showed about 96.7% survival rate after 3 mo. Assessment of genetic integrity of tissue culture raised plantlets was accomplished by DNA–based ISSR primers. A total of 35 bands with an average of 4.38 bands per primer were scored in monomorphic banding pattern. Thus, it is apparent that the mode of in vitro regeneration protocol was suitable for obtaining true-to-type and disease-free plants.

成功开发了一种体外再生系统，该系统可使用衍生自7 d龄树莓幼苗的梢尖（ST）外植体繁殖有价值的药用树-紫檀（Pterocarpus marsupium）。Murashige和Skoog（MS）培养基含有细胞分裂素（BA，米T，或KN），并在不同浓度和组合生长素（NAA，IAA）显示有对再生输出一个标记刺激作用。在细胞分裂素中，间-topolin（m T 7.0μM ）被证明是多芽诱导的最佳剂量，每个植株在6周后70％的培养中每株植株有6.50±0.49个芽，平均芽长（4.00±0.16 cm）。而低浓度的植物生长素（1.0μMNAA）和最佳细胞分裂素（7.0μM）m T）倾向于增加芽诱导并增加响应百分率。在此水平下，在12周后的80％培养中，每个外植体最多可记录13.54±0.34个枝条，平均枝长为（5.30±0.10 cm）。此后，分离出微芽并用高剂量的吲哚-3-丁酸（250μM）处理其基端5 d，然后移植到各种盆栽基质上以进行离体根形成。移植4周后，每微枝最多可发现3.63±0.0.08个根，平均根长为3.59±0.07 cm，具有最高的生根频率（67.7％）。在试管外rooting-暨-驯​​化，发现各种生理参数最初在35 d内波动；此后，观察到净光合速率，细胞间CO ₂浓度和叶绿素a / b估计值呈增加趋势。总体而言，在自然条件下转移时，成功适应环境的再生子在3个月后显示出约96.7％的存活率。通过基于DNA的ISSR引物对组织培养的幼苗的遗传完整性进行评估。共有35条带，每条引物平均4.38条带，以单态条带模式评分。因此，很明显，体外再生方案的模式适合于获得真实型和无病的植物。