Gantait Saikat, Mahanta Manisha
Crop Research Unit (Genetics and Plant Breeding), Bidhan Chandra Krishi Viswavidyalaya, Mohanpur, Nadia, West Bengal, 741252, India.
J Genet Eng Biotechnol. 2021 Nov 15;19(1):175. doi: 10.1186/s43141-021-00269-1.
Gerbera jamesonii Bolus ex Hooker f. (African daisy) is listed among the top five most important ornamental plants in the global floricultural industry. To satisfy its demand, the floriculture industry relies on reproducible and effective propagation protocol while retaining the genetic uniformity of G. jamesonii. The present study, for the first time, reports the potential of picloram for enhanced induction of organogenic calli from leaves of G. jamesonii and its high-frequency indirect regeneration.
The fastest induction of calli with maximum fresh and dry weight was recorded in the Murashige and Skoog (MS) semisolid medium supplemented with 1 mg/l picloram. In addition, callus induction was observed in 2,4-dichlorophenoxy acetic acid- and α-napthaleneaceticacid-supplemented media but with delayed response and reduced fresh and dry weight. The proliferated calli were transferred to shoot induction media containing MS salt and 0.5-1 mg/l N-benzylaminopurine, kinetin, or thidiazuron. A mean number of 6 shoots per callus were developed after 5 days of culture in the MS medium supplemented with 1 mg/l kinetin, with a mean length of 5.2 cm. Successful rooting of shoots was achieved in the MS medium fortified with 1.5 mg/l indole-3-acetic acid, wherein the earliest root initiation (5 days), as well as the maximum number (9) and length (4.8 cm) of roots, were recorded. Complete plantlets were primarily acclimatized in sand before being transferred to a mixed substrate (of soil, sand, tea leaf waste, and cow urine) that secured >90% survival and further growth of the plantlets. Eventually, clonal fidelity of the in vitro regenerants assessed via inter-simple sequence repeats (ISSR) primers exhibited a monomorphic banding patterns that suggested genetic integrity within the plantlets as well as with their mother plant.
The results of the present study should be of interest for commercial propagation and mutagenesis- as well as genetic transformation-related research.
非洲菊是全球花卉产业中最重要的五种观赏植物之一。为满足其市场需求，花卉产业依赖于可重复且有效的繁殖方案，同时保持非洲菊的遗传一致性。本研究首次报道了毒莠定在增强非洲菊叶片器官发生愈伤组织诱导及其高频间接再生方面的潜力。
在添加1 mg/l毒莠定的Murashige和Skoog（MS）半固体培养基中，愈伤组织诱导速度最快，鲜重和干重最大。此外，在添加2,4-二氯苯氧乙酸和α-萘乙酸的培养基中也观察到了愈伤组织诱导，但反应延迟，鲜重和干重降低。将增殖的愈伤组织转移到含有MS盐和0.5-1 mg/l N-苄基腺嘌呤、激动素或噻苯隆的芽诱导培养基中。在添加1 mg/l激动素的MS培养基中培养5天后，每个愈伤组织平均发育出约6个芽，平均长度为5.2 cm。在添加1.5 mg/l吲哚-3-乙酸的MS培养基中，芽成功生根，其中最早的根起始时间（约5天）以及根的最大数量（约9条）和长度（约4.8 cm）均被记录。完整的植株首先在沙子中驯化，然后转移到混合基质（土壤、沙子、茶叶废料和牛粪）中，该基质确保了植株>90%的存活率和进一步生长。最终，通过简单序列重复区间（ISSR）引物评估的离体再生植株的克隆保真度显示出单态条带模式，表明植株及其母本植物内部的遗传完整性。
本研究结果对于商业繁殖、诱变以及遗传转化相关研究具有重要意义。
